ORCID Profile
0000-0002-4670-2783
Current Organisations
University of Bradford
,
Tabriz University of Medical Sciences
,
University of Sydney
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Publisher: Springer Science and Business Media LLC
Date: 30-11-2010
Publisher: Springer Science and Business Media LLC
Date: 11-07-2022
DOI: 10.1007/S10765-022-03061-6
Abstract: The solubility of allopurinol was measured at several temperatures (15–35 ºC) in ethanol–water, ethanol–ethyl acetate, and ethyl acetate–hexane mixtures. The mole fraction solubility shows two solubility maxima against the co-solvent (ethanol) ratio (70 % ethanol–water and 100 % ethyl acetate) at each of the five temperatures studied. The authors correlated the solubility data in binary solvent mixtures at various temperatures using a modified version of the Jouyban–Acree model. The respective apparent thermodynamic functions Gibbs energy, enthalpy, and entropy of solution were obtained from the solubility data through the van’t Hoff equations. The apparent enthalpies of solution are endothermic and display a maximum at 20 % ethanol in water, as ethanol is added to water, the entropy of the system increases. In the non-aqueous mixture (ethanol–ethyl acetate), enthalpy is the driving force throughout the whole solvent composition. An enthalpy–entropy compensation analysis confirms a non-linear enthalpy–entropy relationship in plots of enthalpy vs. Gibbs energy of solution, i.e., two different mechanisms involved in the solubility enhancement. An inverse Kirkwood–Buff integral analysis of the preferential solvation indicated that in ethanol-rich mixtures, the drug is preferentially solvated by water, and it is acting mainly as a Lewis base in front to water.
Publisher: Pleiades Publishing Ltd
Date: 2009
DOI: 10.1134/S0006297909010155
Abstract: In the present study, bovine milk xanthine oxidase activity in various aqueous-organic mixtures and the effects of pH, temperature, and lyophilization on the enzyme activity have been investigated. The enzyme was incubated with xanthine as the substrate in Sorenson's phosphate buffer (pH 7.0) containing 0.1 mM EDTA, and the activity was determined spectrophotometrically in the absence and presence of different fractions of nine water-miscible organic solvents at 27-50 degrees C and at different pH values ranging from 6 to 9. The organic solvents reduced the enzyme activity to different extents. In spite of these inhibitory effects, the enzyme showed relatively good stability in the aqueous-organic mixtures compared with the aqueous medium. A significant increase in the activity of the lyophilized enzyme was observed in pure organic solvents.
Publisher: Elsevier BV
Date: 02-2013
Publisher: Emerald
Date: 30-10-2009
DOI: 10.1108/00346650911002922
Abstract: The antioxidant characteristics of fruits can be attributed to their contents of polyphenols and vitamins. Because of the interest in the role of antioxidants in human health, the purpose of this paper is to examine the major compounds associated with antioxidant activity, namely total phenolic and vitamin C contents, of some regularly cultivated and consumed fruits in Iran. In total, 66 fruits from 22 families were chosen for this study. Terbium sensitized fluorescence assay and spectrophotometric method were used to determine total polyphenol and vitamin C contents respectively. The ANOVA with Tukey post‐hoc test was used for statistical analyses. The total mean polyphenol content of fruits was 4.93 ± 2.86 mg QE/100 g that were ranging from 0.8 ± 0.05 to 11.94 ± 0.02 mg QE/100 g with the lowest amount obtained for pear and the highest amount detected in black grape. The polyphenol contents of black grape, sourcherry and pomegranate were significantly higher than those of other fruits ( p 0.001). The total mean vitamin C content of fresh fruits was 18.34 ± 9.77 mg/100 g that were ranging from 57.38 ± 0.02 (strawberry) to 11.44 ± 0.02 (melon) mg/100 g. The vitamin C contents of strawberry was significantly higher than all other fruits ( p 0.001). Despite the differences in the polyphenol and vitamin C contents of various fruits, as a good source of nutritious compounds and functional foods, they can be effective in enhancing health status. This paper is believed to be the only one which provides information about the polyphenol and vitamin C contents of Iranian fruits. Also, the polyphenol content was measured by using a newly‐developed method.
Publisher: Elsevier BV
Date: 08-2012
DOI: 10.1016/J.CHROMA.2012.06.049
Abstract: Three retention models for liquid chromatography are developed using principal component analysis (PCA). It is shown that they exhibit features similar to that of the model based on linear solvation energy relationship (LSER). However, the fitting performance of the PCA models is better than that of the LSER model, the performance of which can be considerably improved by the use of artificial neural networks. In addition, the possibility of using the proposed models as well as the LSER model to predict the retention times of solutes under chromatographic conditions at which these solutes have never been studied is also examined by means of three data sets of analytes consisting of non-polar compounds to polar compounds with a variety of functional groups.
Publisher: Springer Science and Business Media LLC
Date: 02-2003
DOI: 10.1007/BF02491715
Publisher: Elsevier BV
Date: 07-2022
Publisher: Elsevier BV
Date: 10-2021
Publisher: Maad Rayan Publishing Company
Date: 20-12-2019
DOI: 10.15171/PS.2019.51
Abstract: -
Publisher: Pharmaceutical Society of Japan
Date: 2002
DOI: 10.1248/CPB.50.21
Abstract: Numerical methods to predict the solubility of anthracene in mixed solvents have been proposed. A minimum number of 3 solubility data points in sub-binary solvents has been employed to calculate the solvent-solute interaction terms of a well established colsolvency model, i.e. the combined nearly ideal binary solvent/Redlich-Kister model. The calculated interaction terms were used to predict the solubility in binary and ternary solvent systems. The predicted solubilities have been compared with experimental solubility data and the absolute percentage mean deviation (APMD) has been computed as a criterion of prediction capability. The overall APMD for 25 anthracene data sets in binary solvents is 0.40%. In order to provide a predictive method, which is based fully on theoretical calculations, the quantitative relationships between sub-binary interaction terms and physicochemical properties of the solvents have been presented. The overall APMD value for 41 binary data sets is 9.19%. The estimated binary interaction terms using a minimum number of data points and the quantitative relationships have then been used to predict anthracene solubility data in 30 ternary solvent systems. The produced APMD values are 3.72 and 15.79%, respectively. To provide an accurate correlation for solubility in ternary solvent systems, an extension to the combined nearly ideal multicomponenet solvent/Redlich-Kister (CNIMS/R-K) model was proposed and the corresponding overall AMPD is 0.38%.
Publisher: American Chemical Society (ACS)
Date: 17-07-2014
DOI: 10.1021/JE400576E
Publisher: Informa UK Limited
Date: 17-07-2020
Publisher: Elsevier BV
Date: 06-1998
Publisher: Wiley
Date: 11-2009
Abstract: A mathematical model is proposed for representing the combined effects of mobile phase solvent composition and temperature on the retention of various analytes in HPLC. The applicability of the model in describing the retention of four macrolides in aqueous mixtures of methanol and acetonitrile determined at 20-80 degrees C in various volume fractions of the organic modifiers was shown. The mean percentage deviation (MPD) was computed as an accuracy criterion in which the overall MPD of four analytes investigated in this work was 3.9+/-1.5% (N=72). The proposed model could be reduced to two simpler versions. The first version concerning the retention data of analytes in one organic modifier at various temperatures produced for the retention description of the above experimental system as well as for the retention of three benzodiazepines in aqueous mixtures of methanol at 25-40 degrees C an overall MPD of 3.6+/-1.8%. The more reduced version of the model for calculating the retention factor of one analyte in a given organic modifier at various temperatures produced an overall MPD of 1.7+/-1.1% for both the experimental systems studied. The accuracy of the proposed model is compared with recent models to predict the retention of an analyte with respect to solvent component of the mobile phase and the temperature of column in which the results were comparable. The main advantage of the proposed model is its capability to predict the retention of various analytes considering (i) temperature of the column, (ii) the mobile phase solvent composition, (iii) the chemical structure of the analytes and (iv) the nature of organic modifier.
Publisher: Elsevier BV
Date: 02-2023
Publisher: Springer Science and Business Media LLC
Date: 27-10-2013
Publisher: American Chemical Society (ACS)
Date: 16-01-2018
Publisher: American Chemical Society (ACS)
Date: 06-05-2013
DOI: 10.1021/JE301057G
Publisher: Informa UK Limited
Date: 12-2018
Publisher: Springer Science and Business Media LLC
Date: 15-08-2020
Publisher: Springer Science and Business Media LLC
Date: 17-11-2011
Publisher: Elsevier BV
Date: 10-2018
Publisher: Future Science Ltd
Date: 08-2020
Abstract: Morphine (MO) as an opioid analgesic is used for the treatment of moderate-to-severe pains, particularly cancer-related pains. Pharmacologic studies on MO are complicated due to drugs binding to the protein or metabolization to active metabolites, and even inter-in idual variability. This necessitates the selection of a reliable analytical method for monitoring MO and the concentrations of its metabolites in the biological s les for the pharmacokinetic or pharmacodynamic investigations. Therefore, this study was conducted to review all the analytical research carried out on MO and its metabolites in the biological s les during 2007–2019 as an update to the study by Bosch et al. (2007).
Publisher: Informa UK Limited
Date: 28-06-2018
Publisher: Future Medicine Ltd
Date: 08-2020
Abstract: Biomarkers provide important diagnostic and prognostic information on heterogeneous diseases such as chronic obstructive pulmonary disease (COPD). However, finding a suitable specimen for clinical analysis of biomarkers for COPD is challenging. Exhaled breath condensate (EBC) s ling is noninvasive, rapid, cost-effective and easily repeatable. EBC s ling has also provided recent progress in the identification of biological macromolecules, such as lipids, proteins and DNA in EBC s les, which has increased its utility for clinical scientists. In this article, we review applications involving EBC s ling for the analysis of COPD biomarkers and discuss its future potential.
Publisher: Informa UK Limited
Date: 22-05-2023
Publisher: Bentham Science Publishers Ltd.
Date: 26-10-2020
DOI: 10.2174/1573411015666191203104522
Abstract: Analysis of drug concentrations in biological fluids is required in clinical sciences for various purposes. Among other biological s les, exhaled breath condensate (EBC) is a potential s le for follow up of drug concentrations. A dispersive liquid-liquid microextraction (DLLME) procedure followed by a validated liquid chromatography method was employed for the determination of budesonide (BDS) in EBC s les collected using a homemade setup. EBC is a non-invasive biological s le with possible applications for monitoring drug concentrations. The proposed analytical method is validated according to the FDA guidelines using EBC-spiked s les. Its applicability is tested on EBC s les collected from healthy volunteers receiving a single puff of BDS. The best DLLME conditions involved the use of methanol (1 mL) as a disperser solvent, chloroform (200 μL) as an extraction solvent, and centrifugation rate of 3500 rpm for 5 minutes. The method was validated over a concentration range of 21-210 μg·L-1 in EBC. Inter- and intra-day precisions were less than 10% where the acceptable levels are less than 20%. The validated method was successfully applied for the determination of BDS in EBC s les. The findings of this study indicate that the developed method can be used for the extraction and quantification of BDS in EBC s les using a low cost method.
Publisher: Maad Rayan Publishing Company
Date: 08-03-2019
DOI: 10.15171/BI.2019.14
Abstract: Introduction: Valproic acid (VPA) is an antiepileptic drug used to treat epilepsy and bipolar disorder. Adverse effects of VPA were studied in many reports, however, a dose-response relationship between VPA and its metabolites in epilepsy patients are extremely limited. In this paper, a high efficient method was developed for the preconcentration and determination of VPA and its main metabolite in plasma. Methods: For the extraction and preconcentration of the selected analytes, a volume of an extractant was placed at the bottom of the microtube containing pretreated plasma. The mixture was repeatedly withdrawn from the microtube and pushed-out into it using a 1.0-mL glass syringe and resulted in a cloudy mixture. For further turbidity, the mixture was shaken on a vortex agitator. This procedure was used to analyze the plasma s les of patients with epilepsy (n = 70). Results: The results revealed that in most patients with a low level of VPA relative to its expected level, 3-heptanone concentrations were high. The limits of quantification of 3-heptanone and VPA were 0.04 mg L–1 and 0.2 mg L–1, respectively. A suitable precision at a concentration of 2 mg L-1 for each analyte was obtained (relative standard deviation ≤ 9%). Conclusion: The obtained results indicated that this procedure is easy, sensitive, and reliable, and can be used for the analysis of the selected analytes in the plasma s les of patients with epilepsy.
Publisher: Elsevier BV
Date: 12-2009
DOI: 10.1016/J.BIORTECH.2009.06.044
Abstract: A mathematical model is proposed to calculate the enzyme activity in different concentrations of the organic solvent in hydro-organic mixtures. The accuracy and predictability of the model have been evaluated employing experimentally determined xanthine oxidase activity in five hydro-organic mixtures by using absolute percentage mean deviation (APMD). The obtained APMD for correlative and predictive studies were 5.3% and 7.6%, respectively.
Publisher: Wiley
Date: 02-05-2014
Abstract: In the present study, an in-syringe ultrasound-assisted emulsification-microextraction using a low-density organic solvent was developed for simultaneous extraction and pre-concentration of amlodipine besylate and nifedipine from plasma s les. The extracts were analyzed by high-performance liquid chromatography with UV detection. Central composite design combined with desirability function was applied to find out the optimal experimental conditions providing the highest global extraction efficiency. The optimal conditions identified were volume of the extracting solvent 45 μL, ionic strength 18.95% w/v, sonication time 2.58 min, and centrifugation time 3 min. Under the optimal conditions, the proposed method was evaluated, and applied to the analysis of amlodipine besylate and nifedipine in plasma s les. The validation results of the method indicated a wide linear range (2-1200 ng/mL) with a good linearity (r(2) >0.9991) and low detection limits (0.17 ng/mL for amlodipine besylate and 0.15 ng/mL for nifedipine) with RSD less than 5.2% for both components, both in intra- and inter-day precision studies. The applicability of the proposed in-syringe ultrasound-assisted emulsification-microextraction coupled to high-performance liquid chromatography with UV detection method was demonstrated by analyzing the drugs in spiked plasma s les.
Publisher: Future Medicine Ltd
Date: 12-2020
Abstract: COVID-19 caused by SARS-CoV-2, is an international concern. This infection requires urgent efforts to develop new antiviral compounds. To date, no specific drug in controlling this disease has been identified. Developing the new treatment is usually time consuming, therefore using the repurposing broad-spectrum antiviral drugs could be an effective strategy to respond immediately. In this review, a number of broad-spectrum antivirals with potential efficacy to inhibit the virus replication via targeting the virus spike protein (S protein), RNA-dependent RNA polymerase (RdRp), 3-chymotrypsin-like protease (3CLpro) and papain-like protease (PLpro) that are critical in the pathogenesis and life cycle of coronavirus, have been evaluated as possible treatment options against SARS-CoV-2 in COVID-19 patients.
Publisher: Elsevier BV
Date: 06-2007
Publisher: Elsevier BV
Date: 05-2023
Publisher: Future Science Ltd
Date: 12-2019
Abstract: Verapamil (VER) is a calcium channel blocker that is widely used to treat various cardiovascular diseases and is also effective in migraine prophylaxis. As the therapeutic range of VER is very narrow and toxicity can occur in patients after oral administration, therapeutic drug monitoring is recommended to optimize pharmacotherapy. The choice of an appropriate bioanalytical method for therapeutic drug monitoring of VER in the biological s les is a very important step in achieving fast and reliable results. This review focuses on the various analytical methods reported between 1976 and 2019 for the determination of VER in different biological s les and pharmaceutical dosage forms along with their methodological limitations. This review provides an overview for pharmaceutical industry researchers, clinicians and clinical chemists.
Publisher: Elsevier BV
Date: 12-2008
Publisher: Elsevier BV
Date: 09-2019
Publisher: Maad Rayan Publishing Company
Date: 30-06-2019
DOI: 10.15171/PS.2019.24
Abstract: Background: Recently Sandeepa et al. reported the solubility of benzoic acid in six monosolvents (i.e. tributyl phosphate, diacetone alcohol, methyl-n-propyl ketone, methyl acetate, amyl acetate, and isooctane) and five binary systems (i.e. ethanol + hexane, isopropyl alcohol + hexane and chloroform + hexane, acetone + hexane, and acetone + water) along with some numerical analyses. The reported calculations have been reanalyzed and some recommendations and further computations were proposed. Methods: Further analyses were performed based on combined nearly ideal binary solvent/Redlich-Kister, the modified Wilson model, general single model, Jouyban–Acree model and Jouyban–Acree–van’t Hoff model. Results: The mentioned numerical analyses were used to predict the solubility of benzoic acid in the binary solvent mixtures at various temperatures and the predicted solubility data were compared with their corresponding experimental values by calculating relative deviations. Conclusion: The investigated models provide good estimation of the solubility behavior of benzoic acid in the binary solvent mixtures at various temperatures.
Publisher: Elsevier BV
Date: 04-2003
DOI: 10.1016/S0021-9673(03)00387-X
Abstract: The electrophoretic mobilities of two beta-blocker drugs, i.e., labetalol and atenolol, have been determined in a mixed solvent background electrolyte system containing sodium acetate+acetic acid as buffering agent and different volume fractions of water, methanol and ethanol using capillary electrophoresis. The produced data and three other sets collected from a recent work are employed to study the accuracy and prediction capability of a mathematical model to calculate the electrophoretic mobility with respect to the volume fractions of the solvents in the mixture. The results show that the proposed model is able to correlate redict the mobility within an acceptable error range and it is possible to use the model in industry to achieve the optimum solvent composition for the buffer where using a ternary solvent system is required. The average percentage deviations (APDs) obtained for correlated and predicted data points are 0.71-2.48 and 1.72-4.39%, respectively. The accuracy of the proposed model is compared with that of a mixture response surface method and the results show that the proposed model is superior from both correlation and prediction points of view. The possibility of calculation of the mobility of chemically related drugs in water-methanol-ethanol mixtures using the proposed model is also shown and the produced prediction APD is approximately 8%.
Publisher: Elsevier BV
Date: 09-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D2RA02916B
Abstract: Dispersive solid-phase extraction (DSPE) was developed for the extraction of vanillylmandelic acid (VMA) in urine s les prior to capillary electrophoresis with diode array detection (CE-DAD).
Publisher: American Chemical Society (ACS)
Date: 22-04-2009
DOI: 10.1021/JE900200K
Publisher: Elsevier BV
Date: 11-2023
Publisher: Wiley
Date: 07-2011
DOI: 10.1002/BIO.1218
Abstract: A novel, rapid and sensitive spectroflurimetric method was developed and validated for the determination of deferasirox in urine, serum and tablet s les based on sensitization of terbium fluorescence. The excitation and emission wavelengths were 328 and 545 nm, respectively. The optimum conditions for the determination of deferasirox were investigated considering the effects of various parameters. The method was quantitatively evaluated in terms of linearity, recovery, reproducibility and limit of detection. Under the optimal conditions, the fluorescence intensities were linear with the concentration of deferasirox in the range of 5 × 10(-9) to 5×10(-6) mol L(-1) , with a detection limit of 1.5 × 10(-9) mol L(-1) and a relative standard deviation of 1.1-2.3%. Linearity, reproducibility, recovery and limit of detection made the method suitable for determination of deferasirox in urine, serum and tablets s les.
Publisher: Elsevier BV
Date: 05-2014
DOI: 10.1016/J.MSEC.2014.01.051
Abstract: Polytaurine film was electrodeposited on gold (Au) electrode through cyclic voltammetry from taurine and phosphate buffer solution. The electrocatalytic effect of polytaurine modified Au (PT/Au) electrode was investigated for electro-oxidation of captopril (CAP). Electrocatalytical activity of PT/Au electrode was studied using cyclic voltammetry (CV), chrono erometry and differential pulse voltammetry (DPV). DPV was used to evaluate the analytical performance of CAP in the presence of phosphate buffer solution and good limit of detection was obtained by this sensor. The experimental conditions influencing the determination of CAP were optimized and under optimal conditions, the oxidation peak current was proportional to CAP concentration in the range of 0.06-0.2 μM, while the detection limit was 0.03 μM (S/N=3). The results revealed that PT promotes the rate of oxidation by increasing the peak current. Finally, the applicability of the method to direct assay of human serum is described. The proposed sensor was successfully applied to determine cadaverine in fish s les, yielding satisfactory results. The spiked recoveries were in the range of 96.0-105.0%.
Publisher: Elsevier BV
Date: 04-2013
Publisher: American Chemical Society (ACS)
Date: 28-07-2009
DOI: 10.1021/JE900369W
Publisher: MDPI AG
Date: 20-03-2022
DOI: 10.3390/MOLECULES27061998
Abstract: An important factor affecting the model accuracy is the unit expression type for solute and solvent concentrations. One can report the solute and solvent concentration in various units and compare them with various error scales. In order to investigate the unit and error scale expression effects on the accuracy of the Jouyban–Acree model, in the current study, seventy-nine solubility data sets were collected randomly from the published articles and solute and solvent concentrations in the investigated systems were expressed in various units. Mass fraction, mole fraction, and volume fraction were the employed concentration units for the solvent compositions, and mole fraction, molar, and gram/liter were the investigated concentration units for the solutes. The solubility data, with various solute/solvent concentration units, were correlated using the Jouyban–Acree model, and the accuracy of each model for correlating the data was investigated by calculating different error scales and discussed.
Publisher: American Chemical Society (ACS)
Date: 22-12-2009
DOI: 10.1021/JE900599Q
Publisher: Informa UK Limited
Date: 05-2012
Publisher: Informa UK Limited
Date: 16-04-2018
Publisher: Maad Rayan Publishing Company
Date: 30-12-2018
DOI: 10.15171/PS.2018.43
Abstract: Background: A micellar electrokinetic chromatographic (MEKC)/ indirect UV detection method with hydrodynamic and electrokinetic injection has been developed for the determination of pregabalin in the serum s les. Methods: Separation of the drug was achieved on Agilent capillary electrophorese in less than 5 min using a 50 cm × 75 μm i.d. uncoated fused-silica capillary and a background electrolyte (BGE) consisting of 5-aminosalicylic acid (5-ASA, 10 mmol L-1), cetyl trimethylammonium bromide (CTAB, 1 mmol L-1) and tri-sodium citrate (4% w/v). The influence of various parameters on the separation such as separation voltage, injection time, cassette temperature, pH of BGE and organic modifier was investigated. Results: Method validation shown good linearity (R2 0.999) in the range of 1.5-100 µg mL-1 of pregabalin. A limit of detection (LOD) of 0.8 μg mL-1 and a limit of quantitation (LOQ) of 2.6 μg mL-1 were reported for pregabalin. Conclusion: The proposed method was found to be suitable and accurate for the determination of pregabalin in serum s les.
Publisher: Informa UK Limited
Date: 11-01-2022
Publisher: Informa UK Limited
Date: 06-03-2022
DOI: 10.1080/15257770.2022.2046278
Abstract: Exhaled breath condensate (EBC) is used to investigate the efficacy of EBC to detect the genetic mutations in patients with lung cancer. S les of 5 patients and 5 healthy volunteers were collected. DNA was extracted and used for lification of hotspot regions of
Publisher: Informa UK Limited
Date: 07-06-2021
DOI: 10.1080/10408347.2021.1916733
Abstract: γ-Aminobutyric acid (GABA) plays an important role in regulating neuronal excitability. Four structurally related drugs to GABA including pregabalin (PGB), gabapentin (GBP), vigabatrin (VGB), and baclofen are used for the treatment of central nervous system disorders. These drugs are small aliphatic molecules having neither fluorescent nor strong absorbance in the ultraviolet/visible region therefore, direct determination of these analytes by optical methods is difficult. Additionally, their high boiling point makes gas chromatography impossible. Accordingly, the amine or acid moiety in these drugs is derivatized in order to improve their selectivity and sensitivity during determination in the biological s les. This review focuses on derivatization based methods and their different reactions for determination of PGB, GBP, VGB, and baclofen in the biological s les and pharmaceutical preparations reported between 1980 and 2020. High-performance liquid chromatography methods coupled with different detectors are a commonly used methods for determination of GABA analogs after derivatization. These methods cover 38.89% of all developed methods for determination of GABA analogs.
Publisher: MDPI AG
Date: 27-09-2023
DOI: 10.3390/S23198109
Publisher: Emerald
Date: 14-06-2011
DOI: 10.1108/00070701111140089
Abstract: This paper aims to study the importance of polyphenols in human health and, based on recommendations on the replacement of carbonated drinks with nutritious beverages, like fruit juices, seeks to compare the polyphenol contents of natural and commercial juices. The total polypheol content of 39 fresh and 159 commercial (100 percent and less than 50 percent) fruit juices was analyzed by the terbium sensitized fluorescence method. The ANOVA with Tukey post hoc test, and also an independent t ‐test, were used for statistical analyses. The mean polyphenol contents of fresh juices were significantly ( p .001) higher than those of 100 percent commercials (5.34±2.7 vs 3.28±0.86 mg/l). In fresh juices the concentration ranged from 1.06±0.08 (pineapple) to 10.14±0.07 (sour cherry) mg QE/100 ml, while in 100 percent commercial juices the range was from 2.37±0.05 (orange) to 5.34±0.4 (pomegranate) mg QE/100 ml, and in percent commercial juices they ranged from 1.04±0.7 (red grape) to 2.21±0.07 (white grape) mg QE/100 ml. The polyphenol contents of dark juices, in both fresh and commercial products, were significantly higher than others ( p .001) and most fresh fruit juices possessed higher amounts of polyphenol than commercial ones. Although various juices differed in the quantity of total polyphenol, they can be considered as a good source of functional beverage. This paper provides information about the polyphenol content of fresh and commercial (100 percent and percent) fruit juices. To the best of the authors' knowledge, there have been no articles which aim to compare the polyphenol content of Iranian fresh and commercial fruit juices. For analysing the polyphenol contents, the newly developed terbium sensitized fluorescence method was used, and also the applicability of this new method was compared with the commonly used Folin‐Ciocalteau method.
Publisher: Informa UK Limited
Date: 05-2022
Publisher: Elsevier BV
Date: 2016
DOI: 10.1016/J.EJPB.2015.10.016
Abstract: Stability studies under stress conditions or forced degradation studies play an important role in different phases of development and production of biopharmaceuticals and biological products. These studies are mostly applicable to selection of suitable candidates and formulation developments, comparability studies, elucidation of possible degradation pathways and identification of degradation products, as well as, development of stability indicating methods. Despite the integral part of these studies in biopharmaceutical industry, there is no well-established protocol for the selection of stress conditions, timing of stress testing and required extent of degradation. Therefore, due to the present gap in the stability studies guidelines, it is the responsibility of researchers working in academia and biopharmaceutical industry to set up forced degradation experiments that could fulfill all the expectations from the stability studies of biopharmaceuticals under stress conditions. Concerning the importance of the function of desired stress conditions in forced degradation studies, the present review aims to provide a practical summary of the applicable stress conditions in forced degradation studies of biopharmaceuticals according to the papers published in a time period of 1992-2015 giving detailed information about the experimental conditions utilized to induce required stresses.
Publisher: Informa UK Limited
Date: 05-2022
Publisher: Informa UK Limited
Date: 28-10-2019
Publisher: Informa UK Limited
Date: 22-10-2019
Publisher: Elsevier BV
Date: 10-2009
Publisher: Maad Rayan Publishing Company
Date: 20-12-2019
DOI: 10.15171/PS.2019.43
Abstract: Background: Quantitative analyses of antiepileptic drugs are required in clinic and to rational dosage adjustment, the clinician needs the blood levels of these drugs. A high-performance liquid chromatography with spectrophotometric detection has been developed and validated for simultaneous determination of some antiepileptic drugs in plasma of patients with epilepsy. Methods: A simple procedure based on deproteinization by acetonitrile was used for pre-treatment of plasma s les. Liquid chromatographic analysis was carried out on a Nova-Pak® C18 analytical column, using a ternary mixture of potassium dihydrogen phosphate buffer (pH 6.0)-acetonitrile-2-propanol (63:22:15, v/v/v) as the mobile phase, at a flow rate of 1.0 mL min-1. Results: Calibration curves were linear over a range of 1–40 µg mL-1 for phenobarbital, 1–30 µg mL-1 for phenytoin, 0.3–15 µg mL-1 for carbamazepine and 0.5–6 µg mL-1 for carbamazepine epoxide. Conclusion: The simple s le pre-treatment, combined with the fast chromatographic run was used for the determination of antiepileptic drugs for a large number of patient s les.
Publisher: Springer Science and Business Media LLC
Date: 12-2010
Publisher: Future Science Ltd
Date: 12-2022
Abstract: Aptasensors are amazing among many currently formed procedures due to their excellent particularity, selectivity and responsiveness. These biosensors get more popular in combination with gold nanoparticles (AuNPs) to detect chemical and biological molecules. The response of AuNPs by changing color provides a simple explanation of outcomes. The authors review the recent developments in AuNP-based colorimetric aptasensors designed to sense different chemical and biological molecules. They summarize the procedure of AuNP-based detection and the ordinary instances of currently formed AuNP-based colorimetric procedures. Furthermore, their uses for detecting different analytes based on analyte types are given and the present challenges, overview, and positive views for forming new aptasensors are also regarded.
Publisher: Elsevier BV
Date: 05-2011
DOI: 10.1016/J.COLSURFB.2010.11.036
Abstract: Ion pair of cationic surfactant (cetytrimethylammonium bromide) and tungestosilicic acid incorporated in PVC matrix, was used for coating a piece of copper wire as a new high sensitive SPME fiber in extraction and determination of BTEX compounds from the headspace of water s les prior to GC/FID analysis. Under optimum extraction conditions, limits of detection for benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene were found to be 1.18, 5.61, 0.87, 0.29, 0.22 and 0.33 ng L(-1) respectively. Low detection limits, wide linear dynamic ranges, good reproducibility (RSD% 1.48-4.27), high fiber capacity and high mechanical durability are some of the most important advantages of the new fiber.
Publisher: Elsevier BV
Date: 10-2021
Publisher: Maad Rayan Publishing Company
Date: 29-06-2023
DOI: 10.34172/IA.2023.08
Abstract: The COVID-19 pandemic has resulted in significant morbidity and mortality worldwide, emphasizing the need for effective vaccines. The development of a COVID-19 vaccine requires extensive analysis to ensure its safety and efficacy. In this review, the importance of analytical tools in COVID-19 vaccine development was discussed. A comprehensive literature search using PubMed and Scopus was conducted. Analytical tools play a crucial role in COVID-19 vaccine development, from the initial stages of antigen characterization to vaccine formulation and efficacy testing. The tools used include immunoassay-based methods, separation-based methods, and microscopy. These tools facilitate the characterization of antigens, selection of adjuvants, optimization of formulation, and stability testing. Moreover, analytical tools enable the evaluation of vaccine safety and efficacy, which are necessary for regulatory approval. Therefore, the implementation of analytical tools in COVID-19 vaccine development is crucial in ensuring the timely and successful development of a vaccine to combat the pandemic.
Publisher: Informa UK Limited
Date: 02-11-2017
Publisher: MDPI AG
Date: 26-10-2022
Abstract: Surface tension is among the most important factors in chemical and pharmaceutical processes. Modeling the surface tension of solvents at different temperatures helps to optimize the type of solvent and temperature. The surface tension of solvents at different temperatures with their solvation parameters was used in this study to develop a model based on the van’t Hoff equation by multiple linear regression. Abraham solvation parameters, Hansen solubility parameters, and Catalan parameters are among the most discriminating descriptors. The overall MPD of the model was 3.48%, with a minimum and maximum MPD of 0.04% and 11.62%, respectively. The model proposed in this study could be useful for predicting the surface tension of mono-solvents at different temperatures.
Publisher: Informa UK Limited
Date: 06-06-2018
Publisher: Elsevier BV
Date: 06-2022
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7AY01715D
Abstract: Exhaled breath condensate (EBC) has been proposed as an alternative non-invasive biological s le for therapeutic drug monitoring.
Publisher: Springer Science and Business Media LLC
Date: 06-01-2013
DOI: 10.1007/S12010-012-0036-7
Abstract: In this study, the catalytic activity of aldehyde oxidase was investigated in various water-miscible organic solvents for the first time. The enzyme was partially purified from rabbit liver, and its activity was determined in the absence resence of nine hydro-organic mixtures. The effects of pH and temperature on the enzyme activity were also investigated. The activity was reduced in the presence of all nine organic solvents. However, in some cases, the residual activity remained almost unchanged throughout the incubation of enzyme at 35 °C for 24 h. Considering potential advantages of doing reactions in the presence of organic solvents, these results could be of value. The enzyme showed different behavior in the reaction solutions making it difficult to formulate results in a single comprehensive model. The results indicated that binding and cleavage of the substrate are influenced in the presence of organic solvents.
Publisher: Future Science Ltd
Date: 2012
DOI: 10.4155/BIO.11.294
Abstract: An accurate and precise micellar LC method coupled with UV and fluorimetric detectors was developed and validated for the simultaneous analysis of furosemide, metoprolol and verapamil in human plasma. The total analysis time was 25 min (12 min for s le preparation and 13 min for drug separation). All drugs possessed linear behavior (r 0.999 for calibration curves) in their therapeutic concentrations. The mean drug recoveries were 101.9, 100.1 and 100.2% for furosemide, metoprolol and verapamil, respectively. The accuracies (relative error %) were less than 15% for all drugs. Intra- and inter-day precisions (RSD%) were less than 15% and the stability data were acceptable according to the US FDA guideline for bioanalytical method validation.
Publisher: Elsevier BV
Date: 07-2012
DOI: 10.1016/J.CHROMA.2012.04.046
Abstract: A novel solid-phase microextraction (SPME) fiber based on a glass tube coated with ceramic/carbon coated Fe₃O₄ magnetic nanoparticle nanocomposite (C-Fe₃O₄/C MNP) was prepared by sol-gel technique. The carbon coated Fe₃O₄ magnetic nanoparticles were synthesized by a simple hydrothermal reaction and the resultant powder was mixed with sol-gel precursors to prepare C-Fe₃O₄/C MNP. The prepared C-Fe₃O₄/C MNP was deposited on surface of glass tubes as new substrate with a simple method. The results revealed that this procedure was a simple and reproducible technique for the preparation of SPME fibers coated with magnetic nanoparticles. The scanning electron micrographs of the fiber surface revealed a three-dimensional structure which is suitable as SPME adsorbents. Some polycyclic aromatic hydrocarbons (PAHs) were selected as model compounds for evaluating performance of the designed SPME fiber. The analytes were extracted with SPME, and desorbed using acetonitrile via ultrasonication. The extracts were analyzed by high performance liquid chromatography (HPLC) with fluorescence detection. The results demonstrated that the proposed method based on the C-Fe₃O₄/C MNP fiber had wide dynamic linear range (0.01-350 μg L⁻¹) with good linearity (R²>0.990) and low detection limits (0.7-50 pg mL⁻¹). The relative standard deviation ranged from 6.9% to 12.2% for inter-day variations. These fibers were successfully used for the analysis of spiked water s les, which demonstrating the applicability of the home-made C-Fe₃O₄/C MNP fibers.
Publisher: American Chemical Society (ACS)
Date: 27-02-2008
DOI: 10.1021/JE8000415
Publisher: Wiley
Date: 18-08-2012
DOI: 10.1002/BIO.1344
Abstract: Optimized conditions, validation and practical applications of a new, rapid and specific fluorometric method for the determination of deferiprone (DFP) in urine and serum s les are reported. The proposed method, which is based on the formation of a luminescent complex with Tb(3+) ion, is evaluated in terms of linearity, accuracy, precision, stability, recovery and limits of detection (LOD) and quantification (LOQ). Under optimum conditions (pH 7.5, [Tb(3+)] = 3 × 10(-4) mol/L, temperature 0 °C and excitation wavelength 295 nm), the relative intensities at 545 nm are linear, with the concentration of DFP in the range 0.072-13 mmol/L for urine and serum s les. The LOD and LOQ, respectively, are calculated to be 0.014 and 0.045 mmol/L for urine and 0.022 and 0.072 mmol/L for serum s les. The intra-day and inter-day values for the precision and accuracy of the proposed method are all < 5%, and the recovery of the method is in the range 97.1-103.8%. The method was applied to human urine and serum s les collected from patients receiving DFP. The results indicated that the method can be successfully applied to the determination of DFP in human urine and serum s les collected for clinical or biopharmaceutical investigations in which simple, rapid, cheap and specific determination methods facilitate and speed up the analytical procedure.
Publisher: Informa UK Limited
Date: 27-02-2020
Publisher: Informa UK Limited
Date: 02-03-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0AY00335B
Abstract: Development of an ultrasonication assisted microextraction based on low-density organic solvents coupled with HPLC-UV for extraction/determination of benzo( a )pyrene in exhaled breath condensate (EBC).
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1AY01098K
Abstract: A simple fluorescence probe was developed for sensitive detection of methotrexate in biological s les. The developed probe is based on a silica nanocomposite with a biocompatible nature.
Publisher: Future Science Ltd
Date: 07-2021
Abstract: Aim: A pH-induced homogeneous liquid–liquid microextraction (HLLME) using a new switchable deep eutectic solvent has been used for the extraction of three antiepileptic drugs from breast milk s les. Methodology: This method is based on phase separation by changing pH. An ammonia solution and a phosphocholine chloride: hexanoic acid: p-aminophenol deep eutectic solvents were used as the phase separation agent and extraction solvent, respectively. Results: Significant factors were studied and the detection limits and enrichment factors were in the ranges of 0.009–0.19 ng ml -1 and 182–212 for the analytes, respectively. Also, linear ranges were wide (0.63–500 ng ml -1 ) and the method precision was acceptable. Conclusion: The introduced method was successfully applied for the determination of the analyte concentrations in breast milk s les.
Publisher: Informa UK Limited
Date: 17-08-2018
Publisher: Future Science Ltd
Date: 08-2023
Abstract: Aim: A colorimetric approach for quantification of lamotrigine using spectrophotometric and smartphone image analysis is described in this study. Methods: For full optimization and validation procedures, UV-visible spectroscopy was used, and image analysis was carried out with the help of an app (PhotoMetrix PRO ® ). Then, as a multivariate calibration method, parallel factor analysis was used for data analysis. Results: The results demonstrated the capacity of these methods to estimate lamotrigine concentrations in the range of 0.1–7.0 μg.ml -1 in exhaled breath condensate, indicating the value of using digital images and smartphone applications in combination with chemometric tools. Conclusion: The image analysis can be superior for its fast and reliable lamotrigine analysis in biological s les.
Publisher: Springer Science and Business Media LLC
Date: 10-10-2023
Publisher: American Chemical Society (ACS)
Date: 09-2021
Publisher: Elsevier BV
Date: 11-2023
Publisher: Pharmaceutical Society of Japan
Date: 2006
DOI: 10.1248/CPB.54.1561
Abstract: A numerical method is proposed for predicting solubility of drugs in water-PEG 400 mixtures based on the Jouyban-Acree cosolvency model. The accuracy of the proposed method is evaluated by computing mean percentage deviation (MPD) and compared with that of log-linear model of Yalkowsky. The overall MPDs of the Jouyban-Acree model and the most accurate version of Yalkowsky's model are 39.8 (+/-46.7) % and 175.8 (+/-266.4) %, respectively, and the mean difference is statistically significant (p < 0.0005). The proposed method produces acceptable residual distribution and the probability of solubility prediction with residual log of solubility <0.5 unit is 0.86. The applicability of the proposed method could be extended for predicting the solubility of drugs in water-PEG 400 mixtures at various temperatures. The impact of various log P values computed using different software is also studied and the results of ANOVA revealed that there are no significant differences between the accuracy of the predicted solubilities employing various log P values.
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1AY01833G
Abstract: The efficiency of electromembrane extraction can be improved by modification of supported liquid membrane with various nanomaterials.
Publisher: Springer Science and Business Media LLC
Date: 18-02-2011
Publisher: Informa UK Limited
Date: 28-09-2021
Publisher: Informa UK Limited
Date: 11-07-2014
DOI: 10.1080/09593330.2014.934744
Abstract: Over the last decade, numerous removal methods using solid-supported magnetic nanocomposites have been employed in order to remove arsenic from aqueous solution. In this report, removal of arsenic from aqueous solution by an organo silica, namely, magnetic mobile crystalline material-41 (MCM-41) functionalized by chlorosulphonic acid (MMCM-41-SO3H), was investigated using atomic absorption spectroscopy. The synthesized magnetic mesoporous materials have satisfactory As (V) adsorption capacity. Linearity for arsenic was observed in the concentration range of 5-100 ppb. In addition, the coefficient of determination (R2) was more than 0.999 and the limit of detection (LOD) was 0.061 ppb. Considering these results, MMCM-41-SO3H has a great potential for the removal of As (V) contaminants and potentially for the application in large-scale wastewater treatment plants.
Publisher: Informa UK Limited
Date: 11-04-2012
Publisher: Elsevier BV
Date: 09-2012
Publisher: American Chemical Society (ACS)
Date: 23-08-2021
Publisher: Elsevier BV
Date: 02-0007
Publisher: American Chemical Society (ACS)
Date: 13-04-2021
Publisher: American Chemical Society (ACS)
Date: 31-12-2009
DOI: 10.1021/JE9009514
Publisher: Elsevier BV
Date: 06-2013
Publisher: Elsevier BV
Date: 04-2021
Publisher: Elsevier BV
Date: 05-2008
DOI: 10.1016/J.FOODCHEM.2007.11.008
Abstract: A fast screening of total phenols in tea infusions, tomato and apple juice s les using terbium sensitized fluorescence is described. The proposed method is based on the fluorescence sensitization of terbium (Tb(3+)) by complexation with flavonols (quercein as a reference standard) (at pH 7.0), which fluoresces intensely with an emission maximum at 545nm when excited at 310nm. Quercetin and terbium cations (at pH 7.0) form a stable complex and the resulted emission at 545nm can be used for the determination of the total phenols concentration expressed in terms of "quercetin equivalent". Based on the obtained results, a sensitive, simple and rapid spectrofluorimetric method was developed for the determination of total phenols. In the optimum conditions, the calibration graph was linear from 0.01 to 2μgmL(-1), with the limit of detection of 0.002μgmL(-1). The relative standard deviation values were in the range of 0.75-2.3%. The total concentrations of quercetin equivalent in five tested s les were found in the range of 6.6-27.9μgmL(-1) and the results compare favorably with those obtained by spectrophotometric method (r=0.999).
Publisher: American Chemical Society (ACS)
Date: 09-02-2009
DOI: 10.1021/JE800931Z
Publisher: Elsevier BV
Date: 11-2013
Publisher: Informa UK Limited
Date: 11-03-2021
DOI: 10.1080/10408347.2021.1889961
Abstract: Metabolomics research is rapidly gaining momentum in disease diagnosis, on top of other Omics technologies. Breathomics, as a branch of metabolomics is developing in various frontiers, for early and noninvasive monitoring of disease. This review starts with a brief introduction to metabolomics and breathomics. A number of important technical issues in exhaled breath collection and factors affecting the s ling procedures are presented. We review the recent progress in metabolomics approaches and a summary of their applications on the respiratory and non-respiratory diseases investigated by breath analysis. Recent reports on breathomics studies retrieved from Scopus and Pubmed were reviewed in this work. We conclude that analyzing breath metabolites (both volatile and nonvolatile) is valuable in disease diagnoses, and therefore believe that breathomics will turn into a promising noninvasive discipline in biomarker discovery and early disease detection in personalized medicine. The problem of wide variations in the reported metabolite concentrations from breathomics studies should be tackled by developing more accurate analytical methods and sophisticated numerical analytical alogorithms.
Publisher: Informa UK Limited
Date: 08-04-2019
Publisher: American Chemical Society (ACS)
Date: 16-06-2010
DOI: 10.1021/JE1000632
Publisher: Elsevier BV
Date: 09-2021
Publisher: Elsevier BV
Date: 10-2021
Publisher: Elsevier BV
Date: 10-2003
Publisher: Elsevier BV
Date: 09-2022
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9AY01732A
Abstract: An innovative electrochemical biosensor for the sensitive and specific detection of l -proline ( l -Pro) in human plasma s les was prepared by the encapsulation of proline dehydrogenase on amine functionalized dendritic fibrous nano-silica KCC-1.
Publisher: Wiley
Date: 08-2008
Abstract: This review deals with the determination of impurities in pharmaceuticals by electromigration methods in the capillary format. These separation methods are either based on the different effective mobility of the charged analytes (as in zone electrophoresis and isotachophoresis) or include hybrid methods such as micellar electrokinetic chromatography, microemulsion electrokinetic chromatography and electrochromatography. The pharmaceutically active compounds under consideration belong to chemotherapeutic agents, central nervous system drugs, histamine receptor drugs, cardiovascular drugs, anticancer drugs, anti-inflammatory drugs and some other drugs. The review discusses about 150 publications from the period between 1980 and 2007 with special emphasis on the recent trends and gives details about the experimental conditions applied for analyses and the obtained analytical performance parameters.
Publisher: Pharmaceutical Society of Japan
Date: 2005
DOI: 10.1248/CPB.53.634
Abstract: Organic solvents are amongst the most powerful solubilization agents for a large number of water-insoluble drugs. A number of equations has been reported for mathematical representation of solute solubility in mixed solvents. The question is then posed--is there a mathematical difference between these models? To address this point, it has been demonstrated that all cosolvency models could be made equivalent by using algebraic manipulations. In order to familiarize the readers with the available cosolvency models, they are briefly reviewed. The models can be ided into two mathematical categories, i.e. linear and non-linear models. The linear models include: the log-linear, extended Hildebrand solubility approach, excess free energy equations, combined nearly ideal binary solvent/Redlich-Kister equation and Margule equations which can be converted to a general single model which expresses the logarithm of mole fraction solubility of a solute as a power series of volume fraction of the cosolvent. The non-linear models include the mixture response surface methods, two step solvation model and modified Wilson model which can be converted to a non-linear general form. Also, it has been shown that both the general single model and a non-linear general model are mathematically identical. To show the applicability of the models on real experimental data, 35 data sets have been collected from the literature. Both linear and nonlinear models produced comparable accuracies when an equal number of constant terms was employed in numerical analyses.
Publisher: Elsevier BV
Date: 04-2011
Publisher: Springer Science and Business Media LLC
Date: 19-11-2013
Publisher: Elsevier BV
Date: 09-2014
Publisher: Pharmaceutical Society of Japan
Date: 2006
DOI: 10.1248/CPB.54.428
Abstract: The Jouyban-Acree model has been used to predict the solubility of paracetamol in water-ethanol-propylene glycol binary and ternary mixtures based on model constants computed using a minimum number of solubility data of the solute in water-ethanol, water-propylene glycol and ethanol-propylene glycol binary mixtures. Three data points from each binary solvent system and solubilities in neat solvents were used to calculate the binary interaction parameters of the model. Then the solubility at other binary solvent compositions as well as in a number of ternary solvents were predicted, and the mean percentage deviation (+/-S.D.) of predicted values from experimental solubilities was 7.4(+/-6.1)%.
Publisher: Elsevier BV
Date: 08-2021
Publisher: Elsevier BV
Date: 06-2003
Publisher: Elsevier BV
Date: 08-2021
Publisher: Wiley
Date: 29-03-2022
DOI: 10.1002/BMC.5371
Abstract: A dispersive solid‐phase extraction method based on a new sorbent has been performed on plasma and wastewater s les to determine metoprolol by high‐performance liquid chromatography–tandem mass spectrometry. In this study, the analyte was adsorbed from the s les onto microcrystalline cellulose as a green and efficient sorbent and then eluted for use in the determination step. In the mass spectrometer, the analyte was detected in the positive mode and selectivity of the analysis was increased by sequential mass analysis through multiple reaction monitoring. All of the effective parameters in the extraction of metoprolol from plasma and wastewater were optimized. Under optimal conditions the method was linear in the ranges of 1–1,000 and 0.1–1,000 ng/ml in plasma and wastewater s les, respectively. The detection limits of the method were 0.30 and 0.03 ng/ml in plasma and wastewater s les, respectively. The data showed that the method provides low detection limit, wide linear range, good precision and high extraction recovery. Finally several plasma and wastewater s les were successfully analyzed using the method. The use of a small amount of a green and inexpensive sorbent and a low volume of plasma without the need for further pretreatment steps are the main advantages of the method.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0AY02096F
Abstract: A review of the different analyte detection mechanisms of constant wavelength SFS-based nanosensors for analysis purposes.
Publisher: Informa UK Limited
Date: 13-10-2018
Publisher: Elsevier BV
Date: 09-2022
DOI: 10.1016/J.ADVMS.2022.07.004
Abstract: Serum levels of inflammatory cytokines and uremic toxins, and their inter-correlations with the ersity of Bacteroidaceae, Bifidobacteriaceae, Prevotellaceae and Lactobacillaceae families in intestinal microbiota were investigated in patients with end stage renal disease (ESRD). Stool and blood s les from 20 ESRD patients on maintenance hemodialysis were collected. DNA genome of the bacterial composition of the stool s les was extracted and evaluated by the sequencing analysis of 16S rRNA genes. Serum levels of inflammatory cytokines and uremic toxins were then analyzed. The mean serum concentrations of TNF-α, IL-6, indoxyl sulfate (IS) and p-cresol (PC) were 305.99 ± 12.03 ng/L, 159.95 ± 64.22 ng/L, 36.76 ± 5.09 μg/mL and 0.39 ± 0.15 μg/mL, respectively. The most significant positive correlation was observed between Prevotellaceae family and total antioxidant capacity (TAC), Lactobacilli species and CRP and PC, as well as Scardovia wiggsiae and IS (p < 0.001). A negative correlation was also found between Bacteroides clarus and PC. Patients with ESRD on maintenance hemodialysis had elevated levels of PC and IS and increased levels of the inflammatory markers. The most positive correlation was found between microbiota and CRP and PC, while the most negative one was between microbiota and IL-1 and TAC. The abundance and ersity of Bacteroidaceae, Bifidobacteriaceae, Prevotellaceae and Lactobacillaceae families and their correlations with clinical parameters could provide benefits in the ESRD patients but they could not promote the symptoms.
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7AY00110J
Abstract: Breath analysis is a potential and non-invasive tool for monitoring drugs levels and the status of respiratory or systemic disorders and attracted more attentions in recent years.
Publisher: Informa UK Limited
Date: 30-08-2018
Publisher: Elsevier BV
Date: 09-2011
Publisher: Informa UK Limited
Date: 05-01-2023
Publisher: Elsevier BV
Date: 06-2003
DOI: 10.1016/S0731-7085(03)00093-1
Abstract: Electrophoretic mobility of salmeterol and phenylpropanolamine in capillary electrophoresis has been determined using acetate buffer containing different concentrations of water, methanol and acetonitrile. Maximum electrophoretic mobilities for salmeterol and phenylpropanolamine have been observed at water-methanol-acetonitrile (5:50:45, v/v) and (3:60:37, v/v), respectively, while minimum mobilities of both compounds occurred at methanol-acetonitrile (30:70, v/v). The generated experimental data have been used to evaluate a mathematical model to compute the electrophoretic mobility of the analytes. The proposed model reproduced the mobility data with mean percentage deviations within 1-4%.
Publisher: Springer Science and Business Media LLC
Date: 18-07-2014
Publisher: Elsevier BV
Date: 10-2023
Publisher: Informa UK Limited
Date: 03-07-2018
Publisher: Elsevier BV
Date: 03-2013
Publisher: Informa UK Limited
Date: 27-11-2017
Publisher: American Chemical Society (ACS)
Date: 26-10-2010
DOI: 10.1021/JE100829D
Publisher: Informa UK Limited
Date: 10-05-2019
Publisher: Springer Science and Business Media LLC
Date: 06-11-2021
Publisher: Elsevier BV
Date: 04-2014
Publisher: American Chemical Society (ACS)
Date: 02-04-2021
Publisher: Informa UK Limited
Date: 11-06-2014
Publisher: Elsevier BV
Date: 08-2023
Publisher: Pharmaceutical Society of Japan
Date: 2004
DOI: 10.1248/CPB.52.1219
Abstract: Applicability of a solution model, i.e. Jouyban-Acree model (JAM), for calculating surface tension of binary and ternary solvents at various temperatures has been shown employing experimental surface tension data collected from the literature. The accuracy of the model was evaluated by calculating average percentage deviation (APD) between calculated and observed values. The obtained overall APD (+/-S.D.) for JAM using binary solvent data were 4.06 (+/-4.27) and 8.07 (+/-9.78)%, respectively for correlative and predictive analyses. The corresponding values for the best similar model from the literature were 8.86 (+/-6.40) and 37.10 (+/-27.65)% and the mean APD differences between JAM and previously published model were significant (p<0.003). The capability of JAM for correlating surface tension of ternary solvents at various temperatures was also shown and the overall APD was 1.39 (+/-0.37)%.
Publisher: Pharmaceutical Society of Japan
Date: 2005
DOI: 10.1248/CPB.53.519
Abstract: Applicability of the Jouyban-Acree model for calculating absolute viscosity of binary liquid mixtures with respect to temperature and mixture composition is proposed. The correlation ability of the model is evaluated by employing viscosity data of 143 various aqueous and non-aqueous liquid mixtures at various temperatures collected from the literature. The results show that the model is able to correlate the data with an overall percentage deviation (PD) of 1.9+/-2.5%. In order to test the prediction capability of the model, three experimental viscosities from the highest and lowest temperatures along with the viscosities of neat liquids at all temperatures have been employed to train the model, then the viscosity values at other mixture compositions and temperatures were predicted and the overall PD obtained is 2.6+/-4.0%.
Publisher: Elsevier BV
Date: 12-2013
Publisher: Informa UK Limited
Date: 31-07-2022
Publisher: Elsevier BV
Date: 08-2008
Publisher: American Chemical Society (ACS)
Date: 26-11-2013
DOI: 10.1021/JE400625F
Publisher: Maad Rayan Publishing Company
Date: 21-11-2021
DOI: 10.34172/PS.2021.67
Abstract: Background: Lamotrigine is widely used in the management of partial epilepsy, generalized tonic-clonic epilepsy and Lenox-Gastut syndrome and an add-on therapy in the treatment of complex and simple partial seizures and secondarily generalized tonic-clonic seizures resistant to multiple drug therapy. Methods: In the current study, a fluorometric nanoprobe based on metal–organic frameworks (MOF) was designed for the determination of lamotrigine in exhaled breath condensate (EBC). The MOF nanoprobe consisted of Tb3+ ions as metal part and dimethylformamide (DMF) and 1,10-phenanthroline (Phen) as organic parts of nanoprobe. Results: The used probe shows a week fluorescence in alkaline media owing to an energy transfer from nitrogen groups of DMF and Phen on carbonyl group of DMF as an antenna for Tb3+ luminescence. However, its fluorescence is enhanced in acidic conditions by protonation of DMF nitrogen atoms and Phen and deactivation of energy transfer pathways of nitrogen groups to carbonyl group. Lamotrigine addition to this fluorescent system leads to quenching in the fluorescence intensity due to reactivation of the above mentioned energy transfer pathways resulting in competitive interaction with H+ ions. Moreover, the inner filter effect (IFE) of lamotrigine on DMF–Tb–Phen MOF NPs is considered as another reason for the observed quenching in the fluorescence of DMF–Tb–Phen MOF NPs. The intensity of the fluorescence was recorded at λem = 545 nm and the difference between fluorescence signal in the absence and presence of lamotrigine was the analytical response. The factors affected on experimental conditions were optimized utilizing a multivariate optimization technique. The validation of nanoprobe response to lamotrigine gives a linear relationship in the range of 0.05 to 2.0 µg⋅mL‒1 with a detection limit of 11.0 ng⋅mL‒1 for lamotrigine. Conclusion: The developed method reveals good repeatability and selectivity for lamotrigine in real s les.
Publisher: American Chemical Society (ACS)
Date: 09-04-1999
DOI: 10.1021/ES980761Q
Publisher: American Chemical Society (ACS)
Date: 02-06-2011
DOI: 10.1021/JE2001649
Publisher: Informa UK Limited
Date: 23-03-2021
DOI: 10.1080/10408347.2021.1901646
Abstract: According to the reports of the World Health Organization and the International Agency for Research on Cancer, cancer is the second leading cause of human death worldwide. However, early-stage detection of cancers can efficiently enhance the chance of therapy and saving lives. Metabolomics strategies apply a variety of approaches to discover new potential diagnoses, prognoses, and/or therapeutic biomarkers of various diseases. Metabolomics aims to identify and measure different low-molecular-weight biomolecules in physiological environments. In these studies, special metabolites are extracted from biological s les and identified using analytical techniques. Afterward, using data processing programs discovering significantly associated biomarkers is pursued. In the present review, we aimed to discuss recently reported analytical approaches on the metabolomics studies of gastrointestinal cancers including gastric, colorectal, and esophageal cancers. The gas- and liquid-chromatography with different detectors have been shown that are the main analytical techniques and for metabolites quantification, nuclear magnetic resonance has been utilized as a master method.
Publisher: Pharmaceutical Society of Japan
Date: 2008
DOI: 10.1248/CPB.56.1639
Abstract: A simple and rapid micellar electrokinetic chromatography (MEKC) method was developed for the analysis of an antiviral drug, oseltamivir, and its hydrolyzed product in Tamiflu capsules. Background electrolytes consisted of boric acid 10 mM, pH 10, and sodium dodecyl sulphate (SDS) 40 mM. The limit of detection (LOD) and limit of quantification (LOQ) of oseltamivir were 1.7 and 8.0 microg/ml, respectively. MEKC sweeping in a high electroosmotic flow environment for neutral analytes was also utilized to improve the sensitivity of the assay. In MEKC-sweeping mode, a buffer comprising boric acid 30 mM, pH 10, and SDS 50 mM was used. A 17-fold increase in detection sensitivity was achieved with the MEKC-sweeping method compared with the MEKC mode. Unlike in MEKC, the LOD and LOQ for oseltamivir were 0.1 and 0.3 microg/ml, respectively, using the MEKC-sweeping method. Both methods were successful in determining oseltamivir concentration in its capsule formulation, and the MEKC-sweeping method was capable of determination of the drug at lower concentrations. The hydrolyzed product of oseltamivir (oseltamivir carboxylate) was also detected using the MEKC method. Our observations revealed that the prodrug could be hydrolyzed to the active compound at alkaline pH within ca. 60 min.
Publisher: Elsevier BV
Date: 09-2021
Publisher: Wiley
Date: 26-05-2023
Abstract: A graphene oxide‐based aerogel was synthesized and applied to the extraction and the determinations with the high‐performance liquid chromatography‐ultraviolet detector. After the characterization of the produced graphene‐aerogel, it was utilized as a dispersive solid‐phase extraction sorbent for risperidone extraction from plasma s les. Aerogels are materials with a large surface area‐to‐mass ratio and plenty of core with functional groups which can easily attach to the analytes to extract them to the second phase. The suggested method determined risperidone in plasma s les in the wide dynamic range from 20 ng/ml to 3 μg/ml. The limits of detection and quantification of the developed method were calculated as 2.4 and 8.2 ng/ml, respectively. As a novel feature, the developed method has no need to precipitate plasma proteins, improving the analytical performance of the analysis. Also, for the first time, the produced materials were utilized for the extraction of risperidone from the plasma s les. The obtained results revealed that the developed approach could be employed as an accurate method for the quantification of risperidone in real plasma s les.
Publisher: Informa UK Limited
Date: 26-12-2017
Publisher: Elsevier BV
Date: 23-03-2001
DOI: 10.1016/S0378-5173(00)00694-3
Abstract: The mole fraction solubility of salmeterol xinafoate was determined in various concentrations of dioxane in aqueous binary mixture. Maximum solubility was observed in 90% v/v dioxane and solubility parameter of the solute was estimated from solubility peak equal to 24.99 MPa(0.5). The predicting capability of four different cosolvency models was also evaluated employing a five data point training set. The solubility data at other cosolvent concentrations were predicted using the trained models, with percentage average errors for 28 drug solubility data sets in water-cosolvent mixtures lying between 12.5 and 15.0%. Further predictive model is proposed for accurate solubility predictions based on a minimum number of experiments. The percentage average error where tested was 10.6%.
Publisher: Informa UK Limited
Date: 29-03-2019
Publisher: Informa UK Limited
Date: 25-08-2017
Publisher: Elsevier BV
Date: 02-2017
Publisher: Royal Society of Chemistry (RSC)
Date: 2020
DOI: 10.1039/D0CP03720F
Abstract: In the present work, the influence of Ag-induced plasmons on the surface optical (SO) phonon modes of NiO nanoparticles was extensively studied using room temperature Raman spectroscopy.
Publisher: Springer Science and Business Media LLC
Date: 11-08-2021
Publisher: Elsevier BV
Date: 02-2014
DOI: 10.1016/J.SAA.2013.09.073
Abstract: DNA binding studies of terbium(III)-deferasirox (Tb3+-DFX) complex were monitored to understand the reaction mechanism and introduce a new probe for the assay of DNA. In the present work, UV absorption spectrophotometry, fluorescence spectroscopy, circular dichroism (CD), cyclic voltammetry (CV) and viscosity measurement were employed to study the interactions of Tb3+-DFX with calf thymus DNA (ctDNA). The binding of Tb3+-DFX complex to ctDNA showed a hyperchromic effect in the absorption spectra and the increase in fluorescence quenching effect (amount) of Tb3+-DFX complex in the presence of ctDNA. The binding constants (Kb) for the complex with ctDNA were estimated to be 1.8×10(4) M(-1) through UV absorption spectrophotometry and fluorescence spectroscopy. Upon addition of the complex, clear decreases were observed in the viscosity of ctDNA. The CD spectra indicated that there are certain detectable conformational changes in the DNA double helix when the complex was added. The CV method showed that both anodic and cathodic peak potentials of Tb3+-DFX complex showed negative shifts on the addition of the ctDNA. Further, competitive methylene blue binding studies with fluorescence spectroscopy have shown that the complex can bind to ctDNA through nonintercalative mode. The experimental results suggest that Tb3+-DFX complex binds to DNA via groove binding and/or electrostatic binding mode.
Publisher: American Chemical Society (ACS)
Date: 12-05-2011
DOI: 10.1021/JE101272U
Publisher: Elsevier BV
Date: 10-2010
Publisher: Elsevier BV
Date: 10-2021
Publisher: Elsevier BV
Date: 08-2021
Publisher: Elsevier BV
Date: 10-2013
Publisher: Informa UK Limited
Date: 31-05-2022
Publisher: Elsevier BV
Date: 04-2023
Publisher: Informa UK Limited
Date: 24-05-2023
Publisher: Springer Science and Business Media LLC
Date: 12-07-2011
DOI: 10.1007/S10895-011-0911-6
Abstract: Fluorescence intensities of propranolol and atenolol in binary solvent mixtures at various temperatures are measured and mathematical models are proposed to represent the fluorescence intensity data. The results showed that the proposed models are able to correlate redict the data with reasonable error. The fluorescence intensity of pyridoxal HCl in binary solvents at 25 °C is also determined and represented by the proposed model as an additional test probe.
Publisher: Elsevier BV
Date: 03-2020
DOI: 10.1016/J.SAA.2019.117985
Abstract: Magnetic Fe
Publisher: Elsevier BV
Date: 03-2005
DOI: 10.1016/J.FARMAC.2004.11.011
Abstract: Artificial neural networks were used for modeling the mobility of five beta-blockers (i.e., labetalol atenolol, practolol, timolol and propranolol) in running buffer with ternary solvent background electrolyte systems containing 80 mM acetate buffer dissolved in water, methanol, ethanol and their ternary mixtures. The volume fractions of two solvents (f(2), f(3)) and cologarithm of electrophoretic mobilities in pure solvents (i.e., -Lnmu(1), -Lnmu(2) and -Lnmu(3)) were used as inputs and cologarithm of the mobility in mixed solvents was the output of the networks. The number of neurons in hidden layer, learning rate, momentum and the number of epochs were optimized, in which two neurons in hidden layer, 0.2, 0.9 and 20000 were found the optimized values for learning rate, momentum and number of epochs, respectively. Mean percentage deviations (MPD) between calculated and experimental mobilities were computed as an accuracy criterion. To assess the correlative ability of the model, all data points in each set were used as training set and the mobilities were back-calculated by the trained networks, in which the overall MPD (OMPD)+/- standard deviation (SD) for correlative study was 3.1+/- 2.3. To evaluate the prediction capability of the proposed ANN model, the network was trained using 15 data points for each analyte and the remaining data points were predicted. The obtained OMPD (+/-SD) for this analysis was 3.6+/-3.0. To further investigate on the applicability of ANN, a generalized network was trained with 10 data points from each beta-blocker and then the network was employed to predict the mobilities of the analytes in ternary solvent electrolyte systems. The MPDs for predicted mobilities were 3.6%, 3.6%, 3.9%, 3.7% and 2.9% respectively for labetalol, atenolol, practolol, timolol and propranolol.
Publisher: American Chemical Society (ACS)
Date: 10-05-2010
DOI: 10.1021/JE900852T
Publisher: Informa UK Limited
Date: 12-06-2021
Publisher: Elsevier BV
Date: 09-2021
Publisher: American Chemical Society (ACS)
Date: 17-01-2008
DOI: 10.1021/JE7005049
Publisher: Informa UK Limited
Date: 30-03-2022
Publisher: Informa UK Limited
Date: 10-01-2022
Publisher: Elsevier BV
Date: 09-2014
Publisher: Informa UK Limited
Date: 24-10-2019
Publisher: American Chemical Society (ACS)
Date: 02-02-2017
Publisher: Royal Society of Chemistry (RSC)
Date: 16-10-2001
DOI: 10.1039/B103039F
Abstract: An equation for calculating the electrophoretic mobility of an analyte with respect to the concentration of organic modifier in mixed aqueous-organic modifier running buffer was derived from mixture response surface methodology. In order to assess the accuracy and predictability of the proposed model, the electrophoretic mobilities of four aliphatic amines and imidazole (background absorber) were measured in mixed water-methanol running buffer containing 0-100% v/v methanol by capillary zone electrophoresis with indirect UV detection. The accuracy of the proposed model was examined by fitting all the experimental data points. The predictability of the model was then evaluated by employing six training data points to compute the model constants, and the mobility at the other data points was predicted by the trained model. The proposed model gave accurate results for the correlation and prediction, with mean percentage errors for the amines studied of 0.6% to 0.5% and 1.5% to 1.1%, respectively.
Publisher: Maad Rayan Publishing Company
Date: 18-03-2019
DOI: 10.15171/PS.2019.8
Abstract: Background: In this research, an enhanced fluorimetric assay was developed for the direct monitoring of verapamil in exhaled breath condensate (EBC). The method is based on a binding–induced rigidity inside the sodium dodecyl sulfate (SDS) micelle which eliminate collisional quenching and vibrational modes responsible for non-radiative decay. This process produces an enhancement in the emission intensity of verapamil. Methods: Fluorescence intensity measurements were made at 15 ˚C on a FP-750 spectrofluorometer with maximum excitation and emission wavelengths of 280 nm and 310 nm, respectively. The important parameters influencing the analytical signal in experimental steps were investigated and optimized. The method was validated with considering of the linearity, recovery and limit of detection. Results: Under the optimized experimental conditions, the calibration graph was linear in the range of 0.02 − 12.0 µg.mL−1 of verapamil with a detection limit of 0.008 µg.mL–1. Conclusion: The proposed method was found to be suitable and accurate for the determination of verapamil and the validated method was successfully used for analysis of verapamil in EBC of patients receiving verapamil with the satisfactory results.
Publisher: Informa UK Limited
Date: 18-03-2020
Publisher: Elsevier BV
Date: 10-2016
Publisher: American Chemical Society (ACS)
Date: 10-04-2012
DOI: 10.1021/JE201268B
Publisher: Pharmaceutical Society of Japan
Date: 2002
DOI: 10.1248/CPB.50.594
Abstract: A cosolvency model to predict the solubility of drugs at several temperatures was derived from the excess free energy model of Williams and Amidon. The solubility of oxolinic acid, an antibacterial drug, was measured in aqueous (water+ethanol) and non-aqueous (ethanol+ethyl acetate) mixtures at several temperatures (20, 30, 35, 40 degrees C). Oxolinic acid displays a solubility maximum in each solvent mixture at solubility parameter values of 32 and 22 MPa(1/2). The temperature and heat of fusion were determined from differential scanning calorimetry. The solvent mixtures do not produce any solid phase change during the solubility experiments. The experimental results and those from the literature were employed to examine the accuracy and prediction capability of the proposed model. An equation was obtained to represent the drug solubility changes with cosolvent concentration and temperature. The model was also tested using a small number of experimental solubilities at 20 and 40 degrees C showing reasonably accurate predictions. This is important in pharmaceutics because it save experiments that are often expensive and time consuming.
Publisher: Bentham Science Publishers Ltd.
Date: 02-2013
DOI: 10.2174/1573406411309030014
Abstract: Farnesyltranseferase inhibitors (FTIs) are one of the most promising classes of anticancer agents, but though some compounds in this category are in clinical trials there are no marketed drugs in this class yet. Quantitative structure activity relationship (QSAR) models can be used for predicting the activity of FTI candidates in early stages of drug discovery. In this study 192 imidazole-containing FTIs were obtained from the literature, structures of the molecules were optimized using Hyperchem software, and molecular descriptors were calculated using Dragon software. The most suitable descriptors were selected using genetic algorithms-partial least squares (GA-PLS) and stepwise regression, and indicated that the volume, shape and polarity of the FTIs are important for their activities. 2D-QSAR models were prepared using both linear methods, i.e., multiple linear regression (MLR), and non-linear methods, i.e., artificial neural networks (ANN) and support vector machines (SVM). The proposed QSAR models were validated using internal and external validation methods. The results show that the proposed 2D-QSAR models are valid and that they can be applied to predict the activities of imidazole-containing FTIs. The prediction capability of the 2D-QSAR (linear and non-linear) models is comparable to and somewhat better than that of previous 3D-QSAR models and the non-linear models are more accurate than the linear models.
Publisher: Maad Rayan Publishing Company
Date: 11-07-2027
DOI: 10.34172/PS.2021.39
Abstract: Background: Meloxicam is a powerful analgesic and anti-inflammatory drug widely prescribed by physicians in current therapeutics. Because of the very low aqueous equilibrium solubility of meloxicam, this property has been studied in {2-propanol + water} mixtures from (293.15 to 313.15) K to expand the solubility database about pharmaceutical compounds in mixed solvents useful for homogeneous liquid dosage forms design. Methods: Flask shaken method and UV-vis spectrophotometry were used for meloxicam solubility determinations. Jouyban-Acree model was challenged for solubility correlation. The van’t Hoff and Gibbs equations were employed here to calculate the respective apparent standard thermodynamic quantities for the dissolution and mixing processes, namely Gibbs energy, enthalpy, and entropy. In addition, the inverse Kirkwood-Buff integrals were employed to compute the preferential solvation parameters of meloxicam by 2-propanol in the mixtures. Results: Meloxicam solubility increases with temperature arising and maximum solubilities are observed in the mixture of x1 = 0.70 at all temperatures. Jouyban-Acree model correlates the meloxicam solubility very well. Dissolution processes were endothermic in all cases and entropy-driven in the interval 0.20 ≤ x1 ≤ 1.00. Non-linear enthalpy–entropy relationship was observed in the plot of enthalpy vs. Gibbs energy exhibiting negative but variant slopes in the composition region 0.00 x1 0.40 and variant negative and positive slopes in the other mixtures. Meloxicam is preferentially solvated by water in water-rich mixtures, it is apparently solvated by water in 2-propanol-rich mixtures, but it is preferentially solvated by 2-propanol in the composition interval of 0.19 x1 0.78. Conclusion: Solid-liquid equilibrium of meloxicam in {2-propanol + water} mixtures has been studied at several temperatures as a contribution to preformulation studies of homogeneous liquid pharmaceutical dosage forms based on this drug.
Publisher: FapUNIFESP (SciELO)
Date: 2011
Publisher: Maad Rayan Publishing Company
Date: 23-06-2021
DOI: 10.34172/PS.2021.30
Abstract: Cancer is still a serious disease with high incidence over the past decades. Many anticancer drugs are discovered and used to treat cancer, among them, taxanes such as paclitaxel and docetaxel have high lipophilicity and low aqueous solubility which is further magnified considering the strong need for administering them by intravenous infusion. Currently, the poor water-solubility of taxanes is improved by prodrug formation, conjugation, inclusion complexation, micellar solubilization and liposome-based formulations. Recent achievement for solubilization of taxanes are reviewed and critically discussed regarding their pharmaceutical and chemical applications.
Publisher: Informa UK Limited
Date: 20-08-2014
Publisher: Informa UK Limited
Date: 30-06-2017
Publisher: American Chemical Society (ACS)
Date: 25-10-2012
DOI: 10.1021/JE300980K
Publisher: American Chemical Society (ACS)
Date: 10-06-2014
DOI: 10.1021/JE500368P
Publisher: Informa UK Limited
Date: 29-11-2017
Publisher: Springer Science and Business Media LLC
Date: 12-09-2012
Publisher: Springer Science and Business Media LLC
Date: 16-10-2009
Publisher: Springer Science and Business Media LLC
Date: 22-02-2020
Publisher: Elsevier BV
Date: 05-2014
Publisher: American Chemical Society (ACS)
Date: 07-03-2012
DOI: 10.1021/JE201340E
Publisher: Elsevier BV
Date: 04-2006
Publisher: No publisher found
Date: 2017
Publisher: Informa UK Limited
Date: 05-10-2023
Publisher: Informa UK Limited
Date: 30-06-2019
Publisher: Informa UK Limited
Date: 11-08-2022
Publisher: American Chemical Society (ACS)
Date: 09-11-2021
Publisher: Elsevier BV
Date: 09-2012
Publisher: Elsevier BV
Date: 08-2002
DOI: 10.1016/S0378-5173(02)00276-4
Abstract: The applicability of the combined nearly ideal binary solvent/Redlich-Kister (CNIBS/R-K) equation for quantification of solvent effects on the stability of a solute is shown employing the experimental data of three solutes in different aqueous binary solvents. The proposed model provides a simple computational method to correlate redict the instability rate constant of a drug in mixed solvent systems. The accuracy of the model is compared with that of a model proposed by Connors and co-workers employing various methods including mean percentage deviation (MPD) as comparison criteria. The obtained overall MPD values for the proposed model to correlate and predict the instability rate constants are 2.05 +/- 1.44 and 4.41 +/- 3.21%, respectively, where the corresponding values for Connors' model are 4.34 +/- 3.28 and 10.74 +/- 9.86%. The results suggest that by using only five experimental instability rate constants at different concentrations of the cosolvent in a binary mixture, it is possible to predict unmeasured values falling between data points within an acceptable error range.
Publisher: Informa UK Limited
Date: 21-05-2014
Publisher: Elsevier BV
Date: 06-2020
Publisher: American Chemical Society (ACS)
Date: 17-02-2009
DOI: 10.1021/JE800798D
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C3RA45433A
Publisher: Elsevier BV
Date: 08-2014
Publisher: Springer Science and Business Media LLC
Date: 15-08-2007
Publisher: American Chemical Society (ACS)
Date: 19-09-2012
DOI: 10.1021/JE3005672
Publisher: Springer Science and Business Media LLC
Date: 28-06-2018
Publisher: Informa UK Limited
Date: 10-12-2018
Publisher: Elsevier BV
Date: 12-2011
Publisher: Informa UK Limited
Date: 04-06-2019
Publisher: Informa UK Limited
Date: 14-09-2017
Publisher: Maad Rayan Publishing Company
Date: 30-03-2022
DOI: 10.34172/PS.2022.13
Abstract: Background: To discover the optimal solvent amounts for using in a particular application, it is vital to achieve some useful information in regard with suitable neat or mixed solvent and drugs equilibrium solubility in them. It is known that the low solubility of drugs such as bosentan (BST) in water negatively effects in vitro and in vivo kinetics of dissolution, affecting in turn its bioavailability along with making several difficulties around designing its liquid formulations. Methods: Solubility of BST in some mixtures of polyethylene glycol 400 (PEG 400) and water was experimentally determined at T = (293.15 to 313.15) K by using a common shake-flask technique followed by UV-visible spectroscopic method. The experimental solubility data in PEG 400 mass fraction (w1) of 0.0 to 1.0 at 298.15 K and in w1=0.0, 0.5 and 1.0 at other temperatures were then correlated by cosolvency models including the Jouyban-Acree, the Jouyban-Acree-van’t Hoff, and the double log-log models and some un-measured solubility data were predicted based on the obtained trained models. Results: The results presented that the aqueous solubility of BST is increased by increasing mass fraction of PEG 400 as well as increasing temperature and reached the maximum value in neat PEG 400 at 313.15 K. Conclusion: The BST solubility in water improved by addition of PEG 400 into it. According to the average relative deviations obtained from the back-computed data with trained models which were 8.0%, it concluded that the selected models were able to predict the un-measured data with high reliability.
Publisher: Wiley
Date: 03-2006
Abstract: A discussion is given about the concepts of the ion mobility, the analyte property which governs migration and thus separation selectivity in CE. It deals with small organic and inorganic ions, not with charged polymers or large particles like colloids. The discussion is directed to two main concepts. (i) The first is based on physico‐chemistry of ion conductance in solution, and distinguishes three types of mobility. The absolute mobility is the limiting mobility at zero ionic strength it depends on the solvent and the temperature. It is obtained by extrapolation of the actual mobilities, those of the fully charged particles at finite ion concentration. The observed reduction of the absolute mobility with ionic concentration is related to an ion cloud, and is formulated by the established theories of ion conductance. It explains the actual mobility as function of (beside other factors) the ionic strength, the viscosity and relative permittivity of the solvent, the temperature, the relaxation time of solvent polarisation and the distance of closest approach between ion and counterion. The effective mobility, finally, is the mobility when association and dissociation equilibria play a role. Most important are acid–base reactions, but complexation, ion pairing and homo‐ and heteroconjugation were considered as well. (ii) The second approach treats mobility data with different mathematical methods, and formulates their dependence on variables like solvent composition with appropriate algorithms. These empirical methods mainly include least squares and neural network‐based methods. The least square methods ranges from the simplest model, which uses only the molecular weight of the analyte, to more complicated model requiring three‐dimensional structural descriptors of the solutes. Neural networks have been applied to model the mobility using different input variables and various architectures. Work comparing the accuracy of least squares and neural network methods was discussed the results showed that the neural network method leads to a more accurate mobility calculation. However, the least squares methods could give some information to the factors affecting the mobility of the analytes. The resulting methods allow the prediction of mobilities under different experimental conditions with certain accuracy. It has been shown that using such models, it is possible to predict mobility of analytes after training the models by a minimum number of data to speed up the method development stage.
Publisher: Informa UK Limited
Date: 24-02-2018
Publisher: Maad Rayan Publishing Company
Date: 17-04-2022
DOI: 10.34172/PS.2022.18
Publisher: Elsevier BV
Date: 11-2013
DOI: 10.1016/J.TALANTA.2013.07.040
Abstract: A selective solid phase extraction method, based on nano-structured Mg-Al-Fe(NO3(-)) ternary layered double hydroxide as a sorbent, is developed for the pre-concentration of ultra-trace levels of arsenic (As) prior to determination by electrothermal atomic absorption spectrometry. It is found that both As(III) and As(V) could be quantitatively retained on the sorbent within a wide pH range of 4-12. Accordingly, the presented method is applied to determination of total inorganic As in aqueous solutions. Maximum analytical signal of As is achieved when the pyrolysis and atomization temperatures are close to 900 °C and 2300 °C, respectively. Several variables affecting the extraction efficiency including pH, s le flow rate, amount of nano-sorbent, elution conditions and s le volume are optimized. Under the optimized conditions, the limit of detection (3Sb/m) and the relative standard deviation are 4.6 pg mL(-1) and 3.9%, respectively. The calibration graph is linear in the range of 15.0-650 pg mL(-1) with a correlation coefficient of 0.9979, sorption capacity and pre-concentration factor are 8.68 mg g(-1) and 300, respectively. The developed method is validated by the analysis of a standard reference material (SRM 1643e) and is successfully applied to the determination of ultra-trace amounts of As in different water s les.
Publisher: Maad Rayan Publishing Company
Date: 17-03-2010
DOI: 10.34172/PS.2020.76
Publisher: Elsevier BV
Date: 10-2005
DOI: 10.1016/J.FARMAC.2005.05.011
Abstract: A new, simple, rapid and accurate spectrophotometric method is proposed for determination of sodium diclofenac (SD) in pharmaceutical preparations based on its reaction with concentrated nitric acid (63% w/v). The reaction product is a yellowish compound with maximum absorbance at 380 nm. The corresponding calibration curve is linear over the range of 1-30 mg l(-1), while the limit of detection is 0.46 mg l(-1).
Publisher: Elsevier BV
Date: 03-2015
Publisher: Informa UK Limited
Date: 05-01-2021
Publisher: Informa UK Limited
Date: 02-11-2013
Publisher: Informa UK Limited
Date: 08-08-2020
Publisher: Elsevier BV
Date: 11-2006
Publisher: Elsevier BV
Date: 18-05-1998
Publisher: Maad Rayan Publishing Company
Date: 18-03-2020
DOI: 10.34172/PS.2020.24
Abstract: Background: Because of the narrow therapeutic range of tricyclic antidepressant drugs, their determination in biological s les is of great importance. In this work, a fast and environment friendly s le pretreatment method based on a dispersive liquid–liquid microextraction was developed for the extraction and preconcentration of four tricyclic antidepressants including nortriptyline, amitriptyline, desipramine, and clomipramine in urine prior to their determinations by gas chromatography–mass spectrometry. Methods: In the suggested method, an appropriate mixture of Na2SO4 solution (as phase separation agent and disperser) containing isopropanol (extraction solvent) is rapidly injected into an alkaline aqueous s le solution containing Na2SO4 and the analytes. As a result, a cloudy mixture is formed and the tiny droplets of the extractant containing the extracted analytes are collected on the surface of the aqueous phase after centrifuging. Finally, an aliquot of the collected organic phase is removed and injected into the separation system for the quantitative analysis. Results: Under the optimum conditions, the enrichment factors and extraction recoveries were in the ranges of 380–440 and 76–88%, respectively. The limits of detection and quantification were obtained in the ranges of 11–24, and 41–75 ng/L, respectively. The relative standard deviations of the proposed method were ≤ 6.1% for intra– (n=6) and inter–day (n=4) precisions at a concentration of 100 ng/L of each analyte. Conclusion: The introduced method was satisfactorily utilized for the simultaneous determination of the selected tricyclic antidepressant drugs in the patient’s urine s les.
Publisher: American Chemical Society (ACS)
Date: 25-08-2010
DOI: 10.1021/JE1001945
Publisher: Maad Rayan Publishing Company
Date: 25-12-2020
DOI: 10.34172/PS.2020.20
Publisher: Wiley
Date: 2001
DOI: 10.1002/MCS.10017
Publisher: Elsevier BV
Date: 06-2010
Publisher: Elsevier BV
Date: 02-2000
DOI: 10.1016/S0021-9673(99)01258-3
Abstract: In order to correlate redict electrophoretic mobility data in the mixture of water+organic modifier four equations have been presented and examined. The experimental mobilities of five analytes were determined in a water-methanol mixture. These data have been used to assess the accuracy and predictability of the models. Also, some previously published mobility data in water-organic modifier mixtures has been employed for further evaluation of the models. The models produced accurate results and the means of percentage deviations were in the range of 0.66-1.30.
Publisher: Pharmaceutical Society of Japan
Date: 2006
DOI: 10.1248/CPB.54.1124
Abstract: Quantitative structure property relationships were proposed to calculate the binary interaction terms of the Jouyban-Acree model using coefficients of Abraham solvational models. The applicability of the proposed methods for reproducing solubility data of anthracene in binary solvents has been evaluated using 56 solubility data sets collected from the literature. The mean percentage deviation (MPD) of experimental and calculated solubilities, using predicted mole fraction solubility of anthracene in solvents 1 and 2, has been computed as a measure of accuracy and the MPD of the proposed methods were 5.5 and 4.2%. The accuracy of the method was compared with that of a previously reported method where the MPD was 14.4% and the mean differences between proposed and previous methods was statistically significant. To provide a predictive model, solubility of anthracene was computed using Abraham solvational models and employed to predict the solubility in binary solvents using derived model constants of Jouyban-Acree model and the obtained MPDs were 37.9 and 22.2%, respectively.
Publisher: Elsevier BV
Date: 08-1996
Publisher: Elsevier BV
Date: 05-2012
DOI: 10.1016/J.ETP.2010.10.001
Abstract: Oxidative stress is important factor underlying in a variety of diseases. Antioxidative enzymes such as superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) are part of the physiological defenses against oxidative stress. Malondialdehyde (MDA) is a lipid peroxidation biomarker and its elevated level in various diseases is related to free radical damage. Cysteamine is a cytotoxic agent, acting through generation of reactive oxygen species (ROS) and may decrease defense activity of antioxidative enzymes against ROS and induce duodenal ulcer. Captopril, acts as free radical scavengers and protect against injuries from oxidative damage to tissues.The aim of this study was the evaluation of the effect of captopril against cysteamine-induced duodenal ulcer by determining duodenal damage, duodenal tissue SOD and GSH-PX activities and plasma MAD level. This study was performed on 3 groups of 7 rats each: saline, cysteamine and cysteamine plus captopril treated groups. The effect of captopril against cysteamine-induced duodenal ulcer is determined by evaluating the duodenal damage, duodenal tissue SOD and GSH-PX activities and plasma MDA level. All animals were euthanized 24h after the last treatment and 2 ml blood and duodena s les were collected for calculation of ulcer index, histopathological assessment and measurement of tissue SOD, GSH-PX activities and plasma MDA level. Cysteamine produced severe duodenal damage, decreased the activity of duodenal tissue SOD and GSH-PX and increased the plasma MDA level compared with saline pretreated rats. Pretreatment with captopril decreased the cysteamine-induced duodenal damage and plasma level of MDA and increased the activities of SOD and GSH-PX in duodenal tissue compared with cysteamine pretreated animal. Our results suggest that captopril protects against cysteamine-induced duodenal ulcer and inhibits the decrease in SOD and GSH-PX activities and lipid peroxidation by increasing antioxidant defenses.
Publisher: Springer Science and Business Media LLC
Date: 17-01-2018
Publisher: Springer Science and Business Media LLC
Date: 18-01-2012
Publisher: American Chemical Society (ACS)
Date: 18-05-2018
Publisher: American Chemical Society (ACS)
Date: 14-10-2022
Publisher: Informa UK Limited
Date: 28-10-2020
Publisher: Future Science Ltd
Date: 02-2014
DOI: 10.4155/BIO.13.303
Abstract: Background: A simple and sensitive CE method was developed and validated for the analysis of some beta blockers in human urine. Methods: In this study, salting-out assisted LLE combined with field- lified s le stacking method was employed for biological s le clean-up and sensitivity enhancement in CE. Results: Under the optimal conditions good linearity (r 2 ≥0.998) was obtained, within 0.025–1 µg/ml for propranolol and metoprolol, and within 0.05–1 µg/ml for carvedilol in urine s les. LODs and LLOQs ranged from 0.005 to 0.015 µg/ml, and from 0.025 to 0.05 µg/ml, respectively. The RSDs of intra- and inter-day analysis of examined compounds were less than 4.0%. The recoveries were in the range of 98–119%. Conclusion: The validated method is successfully applied to determine propranolol, metoprolol and carvedilol in human urine s les obtained from the patients who received these drugs.
Publisher: Maad Rayan Publishing Company
Date: 20-09-2020
DOI: 10.34172/PS.2020.14
Publisher: Springer Science and Business Media LLC
Date: 22-10-2013
Publisher: Elsevier BV
Date: 07-2013
Publisher: Maad Rayan Publishing Company
Date: 27-06-2020
DOI: 10.34172/PS.2020.10
Abstract: This article summarizes the publishing activities including bioanalytical and pharmaceutical analyses researches carried out in Iran in 2018 in order to connect academic researchers to those in industry, medical care units and hospitals. A wide spectrum of analytical methods has been used to determine and/or evaluate drug levels in the biological s les, based on physical, chemical and biochemical principles. We have compiled a concise survey of the literature covering 125 reports and tabulated the relevant analytical parameters. Chromatographic and electrochemical methods were found to be the technique of choice for many workers and almost 83% studies were performed by using these methods. This is the first annual review of the literature searching in SCOPUS database for published bioanalytical and pharmaceutical analysis researches in Iran.
Publisher: Elsevier BV
Date: 2004
DOI: 10.1016/J.IJPHARM.2003.09.010
Abstract: A simple computational method for calculating dielectric constants of solvent mixtures based on Redlich-Kister extension was proposed. The model was applied to the experimental dielectric constant of binary and ternary solvent mixtures at fixed and/or various temperatures and showed accurate results. Overall average percentage deviation (OAPD) between calculated and experimental dielectric constants was calculated as an accuracy criterion. The OAPDs for correlative and predictive analyses of dielectric constants in binary solvents at a fixed temperature were 0.56 and 1.42%, respectively. The corresponding values for binary solvents at different temperatures were 1.29 and 1.92%, respectively. The OAPDs for correlative and predictive analyses of dielectric constants of a nonaqueous ternary solvent mixture at various temperatures were 1.61 and 3.05%. The accuracy of the proposed models has also been compared with those of previously published models and results showed that the proposed models were superior and capable of providing more accurate results.
Publisher: Springer Science and Business Media LLC
Date: 28-05-2014
Publisher: Tabriz University of Medical Sciences
Date: 2012
DOI: 10.5681/BI.2012.017
Publisher: Elsevier BV
Date: 08-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 13-08-2002
DOI: 10.1039/B201028N
Abstract: The electrophoretic mobilities of three beta-blocker drugs, practolol, timolol and propranolol, have been measured in electrolyte systems with mixed binary and ternary water-methanol-ethanol solvents with acetic acid/sodium acetate as buffer using capillary electrophoresis. The highest mobilities for the analytes studied have been observed in pure aqueous, the lowest values in ethanolic buffers. The measured electrophoretic mobilities have been used to evaluate the accuracy of a mathematical model based on a mixture response surface method that expresses the mobility as a function of the solvent composition. Mean percentage error (MPE) has been computed considering experimental and calculated mobilities as an accuracy criterion. The obtained MPE for practolol, timolol and propranolol in the binary mixtures are between 0.9 and 2.6%, in the ternary water-methanol-ethanol solvent system the MPE was about 2.7%. The MPE values resulting from the proposed equation lie within the experimental relative standard deviation values and can be considered as an acceptable error.
Publisher: Informa UK Limited
Date: 14-10-2019
DOI: 10.1080/15257770.2019.1677910
Abstract: There is a growing interest in the tracking of genetic and epigenetic alterations in exhaled breath condensate (EBC) s les. The effects of different procedures on the quality and quantity of DNA in EBC were studied. The results demonstrated that sodium acetate precipitation and oligo (dT) improved the quality of the extracted DNA significantly (
Publisher: American Chemical Society (ACS)
Date: 22-12-2008
DOI: 10.1021/JE8007827
Publisher: Maad Rayan Publishing Company
Date: 27-05-2020
DOI: 10.34172/PS.2020.40
Abstract: Background: Ethanol is considered as a toxic compound when used in excess amounts. The toxic concentration for ethanol was reported to be 1000 – 2000 μg.mL-1 in plasma and serum s les. The aim of the current study was to develop a rapid and catalyst free colorimetric method for determination of ethanol in exhaled breath condensate (EBC) s le. Methods: A redox reaction with dichromate-based colorimetric method was used for determination of ethanol in EBC. Results: The proposed method shows a good sensitivity and selectivity for ethanol in compared with other compounds and biomarkers existing in EBC. The color change can be easily observed by the naked eye in the presence of ethanol in the range of 300 - 8000 μg.mL-1. The quantitative detection of ethanol was fully validated and used for determination of ethanol in EBC of alcohol administrated in iduals. Conclusion: This catalyst free colorimetric method has great potential for ethanol determination owing to many desirable properties such as high reliability, high sensitivity, and fast response time.
Publisher: Elsevier BV
Date: 06-2004
Publisher: Wiley
Date: 05-2005
Publisher: Maad Rayan Publishing Company
Date: 10-03-2020
DOI: 10.34172/PS.2019.53
Abstract: Background : Beta-thalassemia major patients require repeated blood transfusion which is associated with iron overload in different organs such as heart, liver, kidney and their related complications. In this study the effects of selenium in iron overload related complications of patients with beta-thalassemia major were assessed. Methods : In this clinical trial, 34 beta-thalassemia major patients over 12 years old were enrolled. Patients with severe renal failure, history of selenium consumption over the last three months, change of blood transfusion pattern, and any change of chelating agent were excluded from the study. For all patients, tablet of selenium 200 µg/day was administered for a month. Blood s les were taken at baseline and after one-month to assess the level of ferritin, total iron-binding capacity (TIBC), aspartate aminotransferase (AST), alanine aminotransferase (ALT), serum creatinine (Scr), selenium. Hair loss was assessed by questionnaire before and after intervention. Results : From 34 patients, 27 (79.4%) had deficient level of selenium at baseline. The selenium level was increased after intervention (p=0.005). The level of serum ALT and Scr decreased remarkably after one-month selenium consumption (p=0.007 for both). In addition, the AST level decreased remarkably after intervention (p=0.053). Severe hair loss profile has improved significantly after supplementation (p=0.004). Conclusion : One-month selenium consumption improved liver and kidney function related markers remarkably. Moreover, selenium improved hair profile and severe hair loss in thalassemia patients. Further studies are needed on the effect of selenium administration on liver and kidney function.
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3CE00853C
Publisher: Mary Ann Liebert Inc
Date: 03-2011
Abstract: The interaction of native calf thymus DNA (CT-DNA) with quercetin-terbium(III) [Q-Tb(III)] complex at physiological pH was monitored by UV absorption spectrophotometry, circular dichroism, fluorescence spectroscopy, and viscosimetric techniques. The complex displays binding properties to the CT-DNA and was found to interact with CT-DNA through outside binding, demonstrated by a hypochromic effect of Q-Tb(III) on the UV spectra of CT-DNA and the calculated association constants (K). Also, decrease in the specific viscosity of CT-DNA, decrease in the fluorescence intensity of Q-Tb(III) solutions in the presence of increasing amounts of CT-DNA, and detectable changes in the circular dichroism spectrum of CT-DNA are other evidences to indicate that Q-Tb(III) complex interact with CT-DNA through outside binding.
Publisher: Elsevier BV
Date: 09-2011
DOI: 10.1016/J.CHROMA.2011.07.034
Abstract: A previously proposed model for representing the retention factor (k) of an analyte in mixed solvent mobile phases was extended to calculate the k of different analytes with respect to the nature of analyte, organic modifier, its concentration and type of the stationary phase. The accuracy of the proposed method was evaluated by calculating mean percentage deviation (MPD) as accuracy criterion. The predicted vs. observed plots were also provided as goodness of fit criteria. The developed model prediction capability compared with a number of previous models (i.e. LSER, general LSER and Oscik equation) through MPD and fitting plots. The proposed method provided acceptable predictions with the advantage of modeling the effects of organic modifiers, mobile phase compositions, columns and analytes using a single equation. The accuracy of developed model was checked using the one column and one analyte out cross validation analyses and the results showed that the developed model was able to predict the unknown analyte retention and the analytes retentions on unknown column accurately.
Publisher: Maad Rayan Publishing Company
Date: 13-06-2020
DOI: 10.34172/PS.2020.46
Abstract: Lung diseases have been recognized as an extensive cause of morbidity and mortality in the worldwide. The high degree of clinical heterogeneity and nonspecific initial symptoms of lung diseases contribute to a delayed diagnosis. So, the molecular and genomic profiling play a pivotal role in promoting the pulmonary diseases. Exhaled breath condensate (EBC) as a novel and potential method for s ling the respiratory epithelial lining fluid is to assess the inflammatory and oxidative stress biomarkers, drugs and genetic alterations in the pathophysiologic processes of lung diseases. The recent studies on the analysis of EBC from both a genetic and epigenetic point of view were searched from database and reviewed. This review provides an overview of the current findings in the tracking of genomic and epigenetic alterations which are potentially effective in better management of cancer detection. In addition, respiratory microbiota DNA using EBC s les in association with pulmonary disease especially lung cancer were investigated. Various studies have concluded that EBC has a great potential for analysis of nuclear and mitochondrial DNA alterations as well as epigenetic modifications and identification of respiratory microbiome. Next-generation sequencing (NGS) based genomic profiling of EBC s les is recommended as a promising approach to establish personalized based prevention, diagnosis, treatment and post-treatment follow-ups for patients with lung diseases especially lung cancer.
Publisher: Future Science Ltd
Date: 12-2021
Abstract: Coronaviruses (CoVs) are a class of viruses that cause respiratory tract infections in birds and mammals. Severe acute respiratory syndrome and Middle East respiratory syndrome are pathogenic human viruses. The ongoing coronavirus causing a pandemic of COVID-19 is a recently identified virus from this group. The first step in the control of spreading the disease is to detect and quarantine infected subjects. Consequently, the introduction of rapid and reliable detection methods for CoVs is crucial. To date, several methods were reported for the detection of coronaviruses. Nanoparticles play an important role in detection tools, thanks to their high surface-to-volume ratio and exclusive optical property enables the development of susceptible analytical nanoparticle-based sensors. The studies performed on using nanoparticles-based (mainly gold) sensors to detect CoVs in two categories of optical and electrochemical were reviewed here. Details of each reported sensor and its relevant analytical parameters are carefully provided and explained.
Publisher: Springer Science and Business Media LLC
Date: 05-2014
Publisher: MDPI AG
Date: 20-09-2022
DOI: 10.3390/BIOS12100773
Abstract: For the first time, a novel aptamer was designed and utilized for the selective detection of rivaroxaban (RIV) using the integration of bioinformatics with biosensing technology. The selected aptamer with the sequence 5′-TAG GGA AGA GAA GGA CAT ATG ATG ACT CAC AAC TGG ACG AAC GTA CTT ATC CCC CCC AAT CAC TAG TGA ATT-3′ displayed a high binding affinity to RIV and had an efficient ability to discriminate RIV from similar molecular structures. A novel label-free electrochemical aptasensor was designed and fabricated through the conjugation of a thiolated aptamer with Au nanoparticles (Au-NPs). Then, the aptasensor was successfully applied for the quantitative determination of RIV in human plasma and exhaled breath condensate (EBC) s les with limits of detection (LODs) of 14.08 and 6.03 nM, respectively. These valuable results provide le evidence of the green electrogeneration of AuNPs on the surface of electrodes and their interaction with loaded aptamers (based on Au-S binding) towards the sensitive and selective monitoring of RIV in human plasma and EBC s les. This bio-assay is an alternative approach for the clinical analysis of RIV and has improved specificity and affinity. As far as we know, this is the first time that an electrochemical aptasensor has been verified for the recognition of RIV and that allows for the easy, fast, and precise screening of RIV in biological s les.
Publisher: Elsevier BV
Date: 07-2003
DOI: 10.1016/S1476-9271(02)00082-8
Abstract: A quantitative structure property relationship (QSPR) is proposed to calculate the electrophoretic mobility of analytes in capillary zone electrophoresis. The proposed model employs logarithm of the electrophoretic mobility (ln micro) as dependent variable and partial charge (PQ), surface area (V(2/3)), total energy (TE), heat of formation (DeltaH(f)) and molecular refractivity (MR) as independent variables whose calculated using AM1 (Austin model 1) semi-empirical quantum mechanics method by HyperChem 7.0 software. The general form of the model is: ln micro =K(0)+K(1)PQ+K(2)V(2/3)+K(3)TE+K(4)DeltaH(f)+K(5)MR, where K(0)-K(5) are the model constants computed using a least-square method. The applicability of the model on real mobility data has been studied employing five experimental data sets of beta-blockers, benzoate derivatives, non-steroidal anti-inflammatory drugs, sulfonamides and amines in different buffers. The accuracy of the model is assessed using absolute average relative deviation (AARD) and the overall AARD value. The obtained AARD for the sets studied are 1.0 (N=10), 2.1 (N=26), 0.8 (N=11), 0.6 (N=13) and 2.7% (N=18), respectively, and the overall AARD is 1.4%. The model is cross-validated using one leave out technique and the obtained overall AARD is 1.8%. To further investigate on the applicability of the proposed model, the prediction capability of the model is evaluated by employing a minimum number of six experimental data points as training set, and predicting the mobility of other data points using trained models. The obtained overall AARD (for 48 predicted data points) is 5.6%.
Publisher: Informa UK Limited
Date: 18-08-2020
Publisher: Informa UK Limited
Date: 24-08-2020
Publisher: Springer Science and Business Media LLC
Date: 07-2019
Publisher: Elsevier BV
Date: 06-1997
Publisher: Informa UK Limited
Date: 22-04-2019
Publisher: Akademiai Kiado Zrt.
Date: 08-2014
Publisher: Springer Science and Business Media LLC
Date: 07-03-2019
Publisher: Informa UK Limited
Date: 19-03-2019
Publisher: Springer Science and Business Media LLC
Date: 07-2009
Abstract: A method was developed for the extraction of valproic acid (VPA) by hollow-fiber coated wire as a lab-made solid-phase microextraction (SPME) fiber and its determination by capillary gas chromatography in human serum and pharmaceutical formulations. In this study, a piece of copper wire coated by polypropylene hollow-fiber membrane was used as a SPME fiber, and its efficiency for the extraction of VPA from the headspace of s les prior to gas chromatographic analysis was evaluated. The optimum conditions of microextraction process were selected, and the limit of detection for VPA was found to be 85 microg L(-1) in solution and 1.7 mg L(-1) in human serum. A low detection limit, a wide linear dynamic range (0.25-100 mg L(-1)), good repeatability (RSD%<4 in formulations and RSD%<7 in serum s les) and a higher mechanical durability due to its metallic base are some of the most important advantages of the proposed fiber.
Publisher: American Chemical Society (ACS)
Date: 14-01-2013
DOI: 10.1021/JE3009842
Publisher: Elsevier BV
Date: 09-2022
DOI: 10.1016/J.ACA.2022.340252
Abstract: In this study, a novel turn-on fluorescence nanoprobe structure has been developed by in situ synthesis and embedding of gold nanoparticles (AuNPs) and Zr-based metal-organic frameworks (MOFs), UiO-66, in polyvinyl alcohol (PVA) hydrogel for sensitive quantification of morphine in human plasma s les. A three-dimensional network of PVA hydrogel was formed by simultaneously penetrating UiO-66 and gold ions in the hydrogel frame and reducing to AuNPs without adding any reducing agent. The morphology and characterization of this new PVA-based nanocomposite hydrogel were studied by transmission electron microscopy, dynamic light scattering instrument, energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. Based on weakened fluorescent intensity resulting from AuNPs binding with Zr node in UiO-66 within PVA matrix, AuNPs@UiO-66 part of the nanocomposite has been employed as a fluorescent sensing probe for selective detection of morphine. The subsequent turn-on of the biocompatible nanoprobe is dependent on the strong binding of morphine with AuNPs on the surface of the UiO-66 frameworks. This platform illustrates a linear calibration curve in the range from 0.02 to 2.0 μg mL
Publisher: National Library of Serbia
Date: 2014
Abstract: Experimental molar solubilities of clonazepam and diazepam in binary and ternary mixtures of polyethylene glycols (PEGs) 400 or 600, propylene glycol (PG) and water (138 data points) along with the density of the saturated solutions at 298.2K were reported. The Jouyban-Acree model was used to fit to the measurements for providing a computational method. Employing the solubilities in the mono-solvents, the measured solubilities in mixed solvents were back-calculated and the overall mean percentage deviations (OMPDs) of the model were 16.0 % and 19.2% for diazepam and clonazepam, respectively. Addition of the Hansen solubility parameters to the model helps us to train all the data sets (clonazepam and diazepam) at once and the back-calculated OMPD for this analysis was 19.3%.
Publisher: Canadian Science Publishing
Date: 06-2006
DOI: 10.1139/V06-082
Abstract: The applicability of previously developed quantitative structure-property relationships was extended to predict the solubility of anthracene in nonaqueous binary and ternary solvent mixtures. The accuracy of the proposed methods was evaluated using 81 solubility data sets collected from the literature. The in idual and mean percentage deviation (IPD and MPD) of experimental and computed solubilities were calculated as accuracy criteria. The computations were carried out using experimental and predicted mole fraction solubility of anthracene in monosolvent systems for binary and ternary solvent systems. The overall MPD of solubility prediction using experimental values in monosolvents varied from 5.2% to 4.2% and from 16.5% to 10.7% for binary and ternary solvents, using water to solvent and gas to solvent solvational parameters, respectively. The IPD distribution was better for the gas to solvent model. The corresponding ranges for the predicted solubility of anthracene in monosolvents were 47.9% to 28.1% and 23.9% to 22.5% for binary and ternary solvents, respectively, and IPD distribution was more favourable for the gas to solvent model. In general, the models derived from gas to solvent coefficients provided more accurate predictions and are recommended for practical applications.Key words: solubility, prediction, cosolvency, anthracene, Abraham model, Jouyban-Acree model.
Publisher: Elsevier BV
Date: 12-2021
Publisher: Future Science Ltd
Date: 06-2014
DOI: 10.4155/BIO.14.118
Abstract: S le preparation is an important step of any biomedical analysis. Development and validation of fast, reproducible and reliable s le preparation methods would be very helpful in increasing productivity. Except for a few direct injection methods, almost all biological s les should at least be diluted before any analysis. Sometimes dilution is not possible because of the low concentration of the target analyte in the s le, and alternative pretreatments, such as filtration, precipitation and s le clean up using different extraction methods, are needed. This review focuses on the recent achievements in the pretreatment of biological s les and investigates them in six categories (i.e., dilution, filtration/dialysis, precipitation, extraction [solid-phase extraction, liquid–liquid extraction], novel techniques [turbulent flow chromatography, immunoaffinity method, electromembrane extraction] and combined methods). Each category will be discussed according to its productivity rate and suitability for routine analysis, and the discussed methods will be compared according to the mentioned indices.
Publisher: Springer Science and Business Media LLC
Date: 07-02-2021
Publisher: Royal Society of Chemistry (RSC)
Date: 2014
DOI: 10.1039/C3RA46973E
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D2RA07902J
Abstract: In the current study, bismuth ferrite nano-sorbent was synthesized and utilized as a sorbent for the dispersive solid-phase extraction of methylprednisolone from exhaled breath s les.
Publisher: Elsevier BV
Date: 05-2002
DOI: 10.1002/JPS.10127
Publisher: Springer Science and Business Media LLC
Date: 06-12-2011
DOI: 10.1007/S12011-011-9270-Z
Abstract: Bronchopulmonary dysplasia (BPD), also known as chronic lung disease, is one of the most challenging complications in premature newborn infants. Selenium plays a role in antioxidant system by protecting cell membranes and neutralizing the deleterious effects of free radicals. The aim of this study was to determine the relationship between selenium concentration and incidence of bronchopulmonary dysplasia using a validated analytical method. Umbilical cord blood and blood s les 30 days after the birth were collected from 38 preterm newborn infants with gestation age of 32 weeks or less, and the separated serums were kept at -70°C until analysis time. Selenium concentration of serum was determined using an atomic absorption spectrophotometer. The method was validated on the basis of standard validation techniques. The analytical method was linear in the range of 1 to 500 μg/L with the limit of detection of 0.4 μg/L. S les were collected from 38 infants whose gestation age was 32 weeks or less. The blood s les were collected from the umbilical cord blood at birth in 19 cases. In 25 cases, blood s les were collected 1 month after birth. Of the 15 patients diagnosed with BPD, 10 were boys (p = 0.02). The mean serum selenium concentration was not different at birth between patients with and without BPD, but it was significantly lower at 30 days after birth in patients with BPD (38.5 ± 14.1vs. 45.4 ± 18.7 μg/L, p = 0.02). Preterm newborn infants with BPD had lower serum selenium concentrations 1 month after birth.
Publisher: Bentham Science Publishers Ltd.
Date: 31-03-2014
Publisher: Elsevier BV
Date: 07-2010
DOI: 10.1016/J.EJMECH.2010.02.055
Abstract: QSAR analyses were performed on a series of trans-stilbenoid diaryl compounds for modeling their COX-2 inhibitory activities. The multivariate regression equations were developed with the selected independent variables using various feature selection methods. In addition, model training was done using different test-train data selection methods. The applicability of each variable and the test-train selection methods was investigated through the type and number of the selected significant descriptors as well as the statistical criteria of the developed model for each pair of feature and test-train selection methods. The goodness of fit and the statistical significance of 15 developed equations were evaluated using the correlation coefficient (R), the variance ratio (F), and the standard error of estimate (S.E.). The models were validated using the leave many out and the leave one out cross-validation methods. The mean percentage deviation (MPD(+/-SD)) was used as an accuracy criterion for checking the predicted activities. It was found that the developed models could predict the COX-2 and COX-1 inhibitory activities as well as the COX-2/COX-1 selectivity ratios producing the MPD values of 1.6(+/-0.8)%, 7.7(+/-5.6)%, and 16.9(+/-9.6)%, respectively.
Publisher: Elsevier BV
Date: 05-2019
DOI: 10.1016/J.BIOS.2019.02.052
Abstract: Functionalized fibrous nano-silica (KCC-1) was applied to specific electrochemical detection of HT 29 colorectal cancer cells based on folate (FA)/folate receptor (FR) interactions. KCC-1 fibrous materials were synthesized using a hydrothermal method and then functionalized with FA molecules to produce KCC-1-NH
Publisher: American Chemical Society (ACS)
Date: 08-10-2009
DOI: 10.1021/JE9000153
Publisher: Elsevier BV
Date: 15-01-1999
Publisher: Informa UK Limited
Date: 05-05-2019
Publisher: Elsevier BV
Date: 08-2011
Publisher: Informa UK Limited
Date: 05-10-2017
Publisher: Wiley
Date: 05-2003
Abstract: Ten different mathematical models representing the electrophoretic mobility of analytes in capillary electrophoresis in mixed solvents of different composition have been compared using 32 experimental data sets. The solvents are binary mixtures of water-methanol, water-ethanol and methanol-ethanol, respectively. Mean percentage deviation (MPD), overall MPD (OMPD) and in idual percentage deviation (IPD) have been considered as comparison criteria. The results showed that a reorganized solution model, namely the combined nearly ideal binary solvent/Redlich-Kister equation, is the most accurate model among other similar models concerning both correlation ability and prediction capability.
Publisher: Informa UK Limited
Date: 03-10-2021
DOI: 10.1080/03639045.2022.2045305
Abstract: Sodium valproate, the most common solid form of valproic acid, is highly hygroscopic and carbamazepine has extremely low aqueous solubility. Producing a salt form of valproic acid with tromethamine and a cocrystal form of valproic acid with carbamazepine have been studied as two approaches to improve physicochemical properties of the intended drugs. Characterization methods including differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform infrared spectroscopy (FTIR) are applied to characterize the synthesized salt and cocrystal. The stability of sodium valproate and tromethamine valproate were examined in 33, 53. 75 and 100 percent of relative humidity. The dissolution profile studies were performed in phosphate buffer media (pH =6.8) for carbamazepine (a low soluble drug) and carbamazepine-valprocic acid cocrystal. Tromethamine valproate was more physically stable than sodium valproate in exposure to humidity. Carbamazepine-valproic acid cocrystal did not show an extreme improvement in dissolution profile when compared to carbamazepine, however after 24 hours carbamazepine-valproic acid cocrystal was more soluble than carbamazepine. Valproic acid forms a new salt with tromethamine and it forms a cocrystal with carbamazepine which can effect on physicochemical properties.
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D2RA06419G
Abstract: Gold nanoparticles (AuNPs) modified with β-cyclodextrin (β-CD) were used to assist with electromembrane extraction (EME) and were coupled with capillary electrophoresis (CE) for the extraction and measurement of methadone from plasma s les.
Publisher: Elsevier BV
Date: 06-2023
Publisher: Elsevier BV
Date: 10-2002
DOI: 10.1016/S0378-5173(02)00355-1
Abstract: A mathematical model for calculating apparent acid dissociation constants (pK(a)) in hydroorganic mixtures with respect to the concentration of organic solvent in a binary mixture is proposed. The correlation ability of the proposed model is evaluated by employing pK(a) value of 75 different weak acids in 13 water-cosolvent systems. The results show that the equation is able to correlate the pK(a) values with an overall mean percentage differences (MPD) of 0.52+/-0.43%. In order to test the prediction capability of the model, four experimental pK(a) values for each data set have been employed to train the model, then the pK(a) values at other solvent compositions predicted and the overall MPD obtained is 1.41+/-1.15%. The applicability of the model to correlate redict pK(a) values of structurally related drugs in a given binary solvent has been shown. The obtained overall MPD for correlation and prediction capabilities are 1.60+/-2.16 and 2.89+/-3.22%, respectively.
Publisher: Elsevier BV
Date: 10-2011
DOI: 10.1002/JPS.22589
Publisher: Pharmaceutical Society of Japan
Date: 2005
DOI: 10.1248/CPB.53.290
Abstract: Applicability of a previously published equation for calculating the solubility of solutes in supercritical carbon dioxide was extended to calculate the solubility in entrained supercritical carbon dioxide employing 42 experimental data sets collected from the literature. The accuracy of the proposed model was evaluated by calculating both the average absolute relative deviation and the in idual absolute relative deviation. The proposed model showed superiority to a previously published similar model, from both correlation and prediction points of view.
Publisher: MDPI AG
Date: 12-08-2022
Abstract: Meloxicam is widely prescribed as an analgesic and anti-inflammatory drug in human therapeutics. Owing the very low aqueous solubility of meloxicam, this property has been studied in dimethyl sulfoxide (DMSO)-aqueous solvent systems at several temperatures from 273.15 to 313.15 K to expand the solubility database about analgesic drugs in mixed solvents. The flask shake method followed by ultraviolet-visible (UV-vis) spectrophotometry analysis were used for meloxicam solubility determinations. A number of cosolvency models, including the Jouyban–Acree model, were challenged for solubility correlation rediction of this drug in these mixtures. The van’t Hoff and Gibbs equations were employed to calculate the apparent standard thermodynamic quantities relative to dissolution and mixing processes. The inverse Kirkwood–Buff integral method was employed for calculating the preferential solvation parameters of meloxicam by DMSO in the mixtures. Meloxicam solubility increases with increasing temperature and maximum solubilities are observed in neat DMSO at all temperatures studied. Dissolution processes were endothermic in all cases and entropy-driven in the composition interval of 0.40 ≤ x1 ≤ 1.00. A nonlinear enthalpy–entropy relationship was observed in the plot of enthalpy vs. Gibbs energy for drug transfer processes. Meloxicam is preferentially solvated by water in water-rich mixtures but preferentially solvated by DMSO in the composition interval of 0.21 x1 1.00.
Publisher: American Chemical Society (ACS)
Date: 14-09-2009
DOI: 10.1021/JE900376R
Publisher: Elsevier BV
Date: 11-2023
Publisher: MDPI AG
Date: 20-09-2023
Publisher: MDPI AG
Date: 25-08-2023
DOI: 10.20944/PREPRINTS202308.1734.V1
Abstract: Real-time monitoring the freshness of food that stored in refrigerator is of great significance to alarm the potential food spoilage and prevent severe health problems. Among those frequently reported methods, discriminating the food freshness through tracking volatile compounds receives extensive attention. Nevertheless, the ambient environment of low temperature (normally below 4oC) and high humidity (90% R.H.) as well as poor selectivity in sensing gas species still remain the challenge. In this research, an integrated smart gas tracking device is deigned and fabricated. Through applying pump voltage on an yttria-stabilized zirconia (YSZ) membrane, oxygen concentration in the testing chamber can be manually tailored. Due to working principle of the sensor follows the mixed potential behavior, distinct difference in sensitivity and selectivity are observed for the sensor that operated at different oxygen concentration. Typically, the sensor gives satisfactory selectivity to H2S, NH3, C2H5OH at the oxygen concentration of 10%, 30% and 40%, respectively. In addition, acceptable response/recovery rate (within 24 s) is also confirmed. Finally, a refrigerator prototype that includes the smart gas sensor is built, and satisfactory performance in discriminate food freshness status of fresh or semi-fresh is verified for the proposed refrigerator prototype. In conclusion, these aforementioned promising results suggest that the proposed integrated smart gas sensor could be a potential candidate for alarming food spoilage.
Publisher: Informa UK Limited
Date: 13-12-2021
Publisher: Springer Science and Business Media LLC
Date: 03-03-2013
Publisher: Elsevier BV
Date: 02-2014
Publisher: American Chemical Society (ACS)
Date: 30-11-2021
Publisher: Informa UK Limited
Date: 25-04-2019
Publisher: Elsevier BV
Date: 07-2021
Publisher: American Chemical Society (ACS)
Date: 21-03-2019
Publisher: Informa UK Limited
Date: 23-07-2018
Publisher: Elsevier BV
Date: 10-2023
Publisher: Informa UK Limited
Date: 29-12-2019
Publisher: Royal Society of Chemistry (RSC)
Date: 2010
DOI: 10.1039/C0AY00254B
Publisher: Elsevier BV
Date: 10-2013
DOI: 10.1016/J.JTEMB.2013.03.006
Abstract: The selenium (Se) is an essential trace element that has a critical role in synthesis and activity of a number of selenoproteins with protective properties against free radical damage. This study was conducted to detect the serum Se concentration in very low birth weight (VLBW) preterm infants and its association with bronchopulmonary dysplasia (BPD). Cord blood Se concentration was determined in 54 neonates with gestation age 30 week or less. Another s le was obtained from these infants at day 28 of birth and serum Se levels were measured by atomic absorption spectrophotometer. All neonates were followed for oxygen dependency at 28 day after birth and 36 week postmenstrual age. The mean cord blood Se concentration in studied neonates was 64.78 ± 20.73 μgL(-1). Serum Se concentration was 60.33 ± 26.62 μgL(-1) at age 28-day. No significant correlation was observed for serum Se concentration at birth and at one month after birth (r = -0.04, p = 0.72). BPD was diagnosed in 25 neonates (46%). The mean serum Se concentration at one month was 57.16 ± 29.68 μgL(-1) in patients with BPD (25 cases) and 63.27 ± 23.6 μgL(-1) in 29 patients without BPD (p = 0.40). In our study, serum Se concentration at 28 day of birth was lower than cord blood levels in preterm neonates, but we have not found significant difference among patients who had BPD or not with respect to serum Se concentrations at this age.
Publisher: Elsevier BV
Date: 08-2010
Publisher: Springer Science and Business Media LLC
Date: 03-2013
Publisher: Springer Science and Business Media LLC
Date: 17-04-2014
Publisher: American Chemical Society (ACS)
Date: 29-04-2019
Publisher: Maad Rayan Publishing Company
Date: 29-12-2021
DOI: 10.34172/IA.2021.12
Abstract: Immunosuppression is associated as a necessary protocol in post-transplantation follow-up to improve graft survival rate. Two typical classes of immunosuppressants that have been commonly used as oral long-term medication are calcineurin inhibitors, e.g. cyclosporine A (CsA) and tacrolimus (TAC), and purine synthesis inhibitor agents, e.g. azathioprine (AZT) and mycophenolate (MF). As a common feature for all of them, they have a narrow therapeutic index which may lead to toxicity or effectiveness of therapy in super therapeutic and subtherapeutic concentrations, respectively. So, despite the undisputed value of immunosuppressants, therapeutic drug monitoring is a vital necessity for post-renal transplantation follow-up to maintain an appropriate balance between a predefined therapeutic dose and toxicity and likelihood adverse effects. Previously, most of the analytical methods that have been employed for immunosuppressant detection are based on immunoassay and chromatography methods which the drawbacks such as expensiveness, time-consuming responding, lack of stability, and skilled persons to interpretation obtained results make them inappropriate platforms for in-situ applications. In this way, we need facile, fast responding analytical methods as like optical and electrochemical sensors which can be developed to use in point-of-care applications. Here, we summarized the analytical methods for the determination of CsA, TAC, AZT, and MF which are based on fast responding methods.
Publisher: American Chemical Society (ACS)
Date: 24-03-2009
DOI: 10.1021/JE900027H
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C9AY01036J
Abstract: A simple and sensitive colorimetric probe based on aggregation of indoxyl sulfate capped silver nanoparticles was proposed for the detection of trace amounts of phenytoin.
Publisher: American Chemical Society (ACS)
Date: 11-05-2017
Publisher: American Chemical Society (ACS)
Date: 31-07-2009
DOI: 10.1021/JE900451D
Publisher: Royal Society of Chemistry (RSC)
Date: 2023
DOI: 10.1039/D3CP01756G
Abstract: Chemiresistive gas sensors are metal oxide-based sensors that have received significant attention in different fields.
Publisher: American Chemical Society (ACS)
Date: 15-06-2009
DOI: 10.1021/JE900330P
Publisher: Informa UK Limited
Date: 16-09-2016
Publisher: Common Ground Research Networks
Date: 2011
Publisher: Pharmaceutical Society of Japan
Date: 2011
DOI: 10.1248/BPB.34.266
Abstract: Two simple multiple linear regression models were proposed to calculate the logarithm of the blood to brain concentration ratio (log BB) of drugs or drug-like compounds. The drugs were classified into two groups according to their ionization state in blood, and the significant parameters were selected using the train sets for each group. For un-ionizable compounds, the logarithm of distribution coefficient in octanol-water in pH 7.4 (log D(7.4)) and molecular weight are the significant parameters, whereas for ionizable compounds, log D(7.4) and number of hydrogen bond acceptor are significant parameters. The developed models were validated and their prediction capabilities checked using an external dataset of 25 compounds. In addition to the acceptable prediction errors, comparison of the external data analysis results with previously proposed models confirmed superior prediction capability of newly developed models.
Publisher: Wiley
Date: 12-02-2020
Publisher: Informa UK Limited
Date: 21-04-2021
Publisher: Informa UK Limited
Date: 28-04-2021
Publisher: Maad Rayan Publishing Company
Date: 30-03-2021
DOI: 10.34172/IA.2021.01
Abstract: The immunoassay area in clinical chemistry began with the development of the first immunoassay for insulin by Solomon Berson and Rosalyn S. Yalow in 1959. Their work resulted in their receipt of the Nobel Prize in Physiology or Medicine in 1977. The radioimmunoassay for insulin has paved the way for the development of immunoassays for thousands of other analytes over the ensuing half a century. A decision by Drs. Berson and Yalow to not patent this technology accelerated the progress of immunoassay development. Immunoassay technology continues to evolve with new applications and improved analytical platforms. The future appears to be headed in two directions: continued improvement in immunodetection methods for very high-sensitivity applications, and multiplex analysis. During 1995–2021, a wide range of immunoassays has been developed to provide the quantitative, semi-quantitative, or qualitative detection of analytes in various bioanalytical settings, such as clinical diagnostics, biopharmaceutical analysis, environmental monitoring, security, and food testing. However, there is only one specialized journal in this field namely "Journal of Immunoassay and Immunochemistry". ImmunoAnalysis as the second journal in this field will provide a platform for the publication of studies on all scientific aspects of immune analysis, including developing bioanalytical methods such as quantification of small molecules, peptides, proteins, antibodies, biomarkers, and immunoassay methods, and studies in immunology field such as innate immunity and inflammation immune receptors, cellular and systemic immunity vaccines immune tolerance autoimmunity, tumor immunology, and microbial immunopathology. It is a peer-reviewed, platinum open access journal (no processing or publication fees) intended to maintain the highest possible global scientific standards. We acknowledge the support from TUOMS press in making use of their facilities and for hosting the journal. The members of the editorial board by using their wide range of perspectives and expertise make a journal that will be an indispensable resource and a sum of parts offering something new to forthcoming studies. We have been buoyed and empowered by their supports. Crucially, of course, those reviewers who will spend their time and energy to assess submissions are a fundamental part of this endeavor. Finally, starting this journal is not meant to provide just another "outlet" for papers, but stems from the ambition to continue, develop and start important discussions in the field of immune analysis. We warmly invite you to join us as reviewers and authors to speed up the growth of this journal. The issues ImmunoAnalysis considers are yours.
Publisher: Springer Science and Business Media LLC
Date: 05-2021
Publisher: Maad Rayan Publishing Company
Date: 20-01-2022
DOI: 10.34172/PS.2022.1
Publisher: Elsevier BV
Date: 07-2014
Publisher: American Chemical Society (ACS)
Date: 21-05-2010
DOI: 10.1021/IE100002Y
Publisher: Royal Society of Chemistry (RSC)
Date: 2017
DOI: 10.1039/C7AY01535F
Abstract: A novel fluorometric sensor based on catalyzed 5-aminosalicylic acid (5-ASA)/H 2 O 2 systems was developed to detect trace levels of H 2 O 2 in exhaled breath condensate (EBC).
Publisher: American Chemical Society (ACS)
Date: 04-08-2014
DOI: 10.1021/JE500497Q
Publisher: Informa UK Limited
Date: 17-10-2018
DOI: 10.1080/03639045.2018.1529786
Abstract: The solubility of drugs is a crucial physicochemical property in the drug discovery or development process and for improving the bioavailability of drugs. There are various methods for evaluating the solubility of drugs including manual measurement methods, mathematical methods, and smart methods. Manual measurement and mathematical methods have some defects which make the smart systems more reliable and important in this field. In this review, various instruments used for the solubility determination, along with the smart systems, have been discussed. Mechanism and applications of each method have been elaborated in detail. Moreover, unique characteristics as well as some limitations of discussed methods are also described.
Publisher: Hindawi Limited
Date: 2012
DOI: 10.1100/2012/940541
Publisher: Elsevier BV
Date: 06-2011
DOI: 10.1016/J.FOODCHEM.2010.11.160
Abstract: A simple spectrofluorimetric method is described for the determination of buparvaquone (BPQ), based on its quenching effect on the fluorescence intensity of Tb(3+)-deferasirox (DFX) complex as a fluorescent probe. The excitation and emission wavelengths were 328 and 545nm, respectively. The optimum conditions for determination of BPQ were investigated considering the effects of various affecting parameters. The variations in fluorescence intensity of the system showed a good linear relationship with the concentration of BPQ in the range of 10-1500μgL(-1), its correlation coefficient was 0.999 with the detection and quantification limits of 1.1 and 3.4μgL(-1), respectively. Linearity, reproducibility, recovery, limits of detection and quantification made the method suitable for BPQ assay in biological fluids, meat, dairy products and BPQ parenteral solutions (vials). The method was applied to real s les of serum and milk of three cows receiving BPQ.
Publisher: Bentham Science Publishers Ltd.
Date: 11-03-2021
DOI: 10.2174/1573411016666200319101416
Abstract: Tramadol, (±)-trans-2-[(dimethylamino) methyl]-1-(3-methoxyphenyl) cyclohexanol, is a synthetic centrally acting analgesic used in the treatment of moderate to chronic pain. Tramadol, like other narcotic drugs, is used for the treatment of pain and may also be abused. Its overdose can cause adverse effects such as dizziness, vomiting, and nausea. The aim of this paper is to develop a s le preparation method for the determination of tramadol in human plasma s les, followed by CE analysis. Ultrasound assisted-dispersive liquid-liquid microextraction using binary mixed extractant solvent (chloroform and ethyl acetate) was used for the extraction of one hundred microliters of tramadol spiked human plasma s les and in real human plasma s les obtained from the patients with abuse of tramadol. After evaporation of the extractant solvent, the residue was reconstituted in 100 μL deionized water and subsequently analyzed by CE-UV. The developed method has remarkable characteristics, including simplicity, good repeatability and appreciable accuracy. Under the best extraction conditions, a low limit of detection at 7.0 μg per liter level with good linearity in the range of 0.02-10 μg mL -1 was obtained. UA-DLLME, using a binary mixed extraction solvent, was established for the determination of tramadol in human plasma s les via the CE method with UV-detection. In addition, the analysis of tramadol in some plasma s les of patients with abuse of tramadol indicated that the method has acceptable performance for the determination of tramadol in plasma s les, which indicates that the method is suitable for clinical applications.
Publisher: Elsevier BV
Date: 09-2001
Publisher: Pharmaceutical Society of Japan
Date: 2010
DOI: 10.1248/CPB.58.219
Abstract: Experimental solubilities of acetaminophen and ibuprofen in polyethylene glycol 600-water, ethanol-polyethylene glycol 600, and polyethylene glycol 600-water-ethanol mixtures at 25 degrees Celsius are reported. The solubilities of drugs in the presence of ethanol and polyethylene glycol 600 were increased. The Jouyban-Acree model was used to fit the solubility data of each drug in the binary mixtures in which the overall mean relative deviations (OMRDs) for acetaminophen and ibuprofen were 2.9% and 4.3%, respectively. The OMRDs for ternary solvent mixtures for acetaminophen and ibuprofen were 16.8% and 22.4%, respectively. Generally, the errors associated with ibuprofen are larger than that of acetaminophen in both binary and ternary solvent mixtures. The solubilities were predicted using previously trained versions of the Jouyban-Acree and log-linear models with the OMRDs of 38.8% and 52.1%, respectively. Density of the mixed solvents in the absence of the solute was measured and used to train the model and then the density of the saturated solutions was predicted using the trained model and the density of the saturated solutions in mono-solvent systems with the OMRD of 3.2%.
Publisher: Informa UK Limited
Date: 10-02-2022
Publisher: Future Science Ltd
Date: 09-2020
Publisher: Elsevier BV
Date: 04-2005
Publisher: Bentham Science Publishers Ltd.
Date: 13-08-2020
DOI: 10.2174/1573411015666190617105034
Abstract: Uremia is the outcome of the remaining of nitrogenous waste products that are normally removed by the kidneys. Para-cresol (4-methylphenol) can be regarded as a proteinbound uremic toxin. The p-cresol determination in sera is necessary since it is a marker of cardiovascular risk and overall mortality in hemodialysis patients. Among the reported methods, chromatographic ones especially HPLC techniques due to the high sensitivity, selectivity and reproducibility have been extensively exploited in analysis of p-cresol in complex mixtures. However, an appropriate s le preparation prior to analysis is necessary for obtaining accurate and precise results. In this study, the appropriate precipitating agent for p-cresol determination in plasma s les was investigated. Then, in situ surfactant-based solid phase microextraction followed by HPLCFL detection was developed and validated for the quantification of p-cresol in plasma s les. According to the results, HCl/heat precipitation method was used for p-cresol microextraction from from plasma s les. In situ surfactant-based solid phase microextraction using cetyltrimethylammonium bromide as extraction medium was proposed for pretreatment of plasma s les prior to analysis. The separation was achieved by isocratic elution with sodium acetate buffer (pH 3.8) and acetonitrile (20:80, v/v). Linearity was found to be acceptable over the concentration ranges of 0.5 to 8 μg mL-1 with the limit of detection and quantification of 0.324 and 0.422 μg mL-1, respectively. The variations for intra-day and inter-day precisions were both less than 8.2% and the extraction recoveries were more than 97%. A validated ISS-SPME followed by HPLC-FL detection reported to determine the total p-cresol concentration of human plasma s les. The traditional liquid-liquid extraction techniques are normally time consuming and require the use of large amounts of toxic organic solvents. In addition, the evaporation of extraction solvent and dissolving the analyte in the mobile phase is commonly used before HPLC analysis. Such a requirement makes the s le preparation process even more tedious and time consuming. ISS-SPME that is the developed ISS-SPE in micro scale, is a simple, rapid and effective s le preparation technique that is appropriate for HPLC-FL analysis.
Publisher: American Chemical Society (ACS)
Date: 19-07-2008
DOI: 10.1021/JE800386D
Publisher: Informa UK Limited
Date: 04-11-2017
Publisher: Informa UK Limited
Date: 14-03-2022
Publisher: Informa UK Limited
Date: 06-03-2022
Publisher: Elsevier BV
Date: 06-2009
Publisher: American Chemical Society (ACS)
Date: 23-08-2008
DOI: 10.1021/JE800397Z
Publisher: Royal Society of Chemistry (RSC)
Date: 2019
DOI: 10.1039/C8AY02286K
Abstract: This study presents a microscale spectrophotometric method for the determination of doxorubicin, one of the most important anticancer drugs in the clinic, based on the localized surface plasmon resonance property of silver nanoparticles.
Publisher: MDPI AG
Date: 08-2022
Abstract: The equilibrium solubility of benzoic acid in water and ethanol, as well as in nine {ethanol (1) + water (2)} mixtures, was determined from T = (293.15 to 323.15) K. Benzoic acid mole fraction solubility in these aqueous-ethanolic mixtures was adequately correlated with some well-known correlation rediction models, obtaining mean percentage deviations of 2.2 to 7.6%. Apparent thermodynamic quantities, namely, Gibbs energy, enthalpy, and entropy, for the dissolution, mixing and solvation processes, were computed by means of the van ’t Hoff and Gibbs equations. The enthalpy–entropy compensation plot of apparent enthalpy vs. apparent Gibbs energy of dissolution was not linear, indicating enthalpy and entropy mechanisms for transfer. Ultimately, by using the inverse Kirkwood–Buff integrals, it is observed that benzoic acid is preferentially solvated by water molecules in water-rich mixtures but preferentially solvated by ethanol molecules in those {ethanol (1) + water (2)} mixtures of 0.24 x1 1.00.
Publisher: Elsevier BV
Date: 07-2021
Publisher: Elsevier BV
Date: 15-01-1999
Publisher: Elsevier BV
Date: 11-2004
Publisher: Informa UK Limited
Date: 23-11-2020
Publisher: Informa UK Limited
Date: 13-05-2020
Publisher: Informa UK Limited
Date: 04-12-2020
DOI: 10.1080/07391102.2020.1854858
Abstract: The intercalation DNA binding mode of the naproxen, a non-steroidal anti-inflammatory drug, has been reported previously. In this study, calf thymus deoxyribonucleic acid (CT-DNA) binding of zinc-naproxen complex, [Zn(naproxen)
Publisher: Pharmaceutical Society of Japan
Date: 2008
DOI: 10.1248/CPB.56.602
Abstract: The solubility of paracetamol in water-ethanol-propylene glycol binary and ternary mixtures at 25 and 30 degrees C was determined using flask shake method. The generated data extended the solubility database for further computational investigations and also was used to assess the prediction capability of the Jouyban-Acree model. A new version of the model was proposed for modeling the solubility data in water-cosolvent mixtures with the cosolvent concentration of <50% which is required in pharmaceutical formulations. The accuracy of the predicted solubilities was evaluated by the mean percentage deviation (MPD) between the predicted and experimental solubilities. The overall MPD of the Jouyban-Acree model and the log-linear model of Yalkowsky for the entire composition range of the cosolvents were 11.0+/-8.7 and 55.4+/-17.8%, respectively the corresponding values for the predicted solubilities in mixtures having a cosolvent concentration of <50% were 12.0+/-9.1 and 22.0+/-11.0%.
Publisher: Springer Science and Business Media LLC
Date: 2011
Publisher: Informa UK Limited
Date: 2000
Abstract: Applicability of the combined, nearly ideal, binary solvent/Redlich-Kister equation for calculating drug solubility in ternary mixtures is presented. The advantages of the proposed model are discussed and compared with a recently published equation that calculates the solute solubility in ternary solvent mixtures based on the mixture response methodology.
Publisher: Elsevier BV
Date: 03-2021
Publisher: American Chemical Society (ACS)
Date: 23-10-2009
DOI: 10.1021/JE9005807
Publisher: Wiley
Date: 03-2011
DOI: 10.1002/BIO.1191
Abstract: A new spectrofluorimetric method was reported for the determination of folic acid (FA), based on its quenching effect on the fluorescence intensity of Tb(3+) -1,10-phenanthroline complex as a fluorescent probe. The quenched fluorescence intensity at an emission wavelength of 545 nm was proportional to the concentration of FA in Tris-HCl buffer solution of pH 6.2. The effects of pH, time, order of addition of reagents, temperature and concentrations of Tb(3+) , buffer and 1,10-phenanthroline were investigated and optimized. The linear range for the determination of FA was 0.01-1.1 mg/L. The detection limit was 0.003 mg/L and the relative standard deviation for replicated determination of 1 mg/L of folic acid was 1.2%. This method was simple, practical and relatively free from interference effects. It was successfully applied to assess FA in pharmaceutical tablets and urine s les.
Publisher: American Chemical Society (ACS)
Date: 30-09-2013
DOI: 10.1021/IE402588T
Publisher: Hindawi Limited
Date: 2013
DOI: 10.1155/2013/501310
Abstract: Detailed information about the relationships between structures and properties/activities of peptides as drugs and nutrients is useful in the development of drugs and functional foods containing peptides as active compounds. The bitterness of the peptides is an undesirable property which should be reduced during drug/nutrient production, and quantitative structure bitter taste relationship (QSBR) studies can help researchers to design less bitter peptides with higher target efficiency. Calculated structural parameters were used to develop three different QSBR models (i.e., multiple linear regression, support vector machine, and artificial neural network) to predict the bitterness of 229 peptides (containing 2–12 amino acids, obtained from the literature). The developed models were validated using internal and external validation methods, and the prediction errors were checked using mean percentage deviation and absolute average error values. All developed models predicted the activities successfully (with prediction errors less than experimental error values), whereas the prediction errors for nonlinear methods were less than those for linear methods. The selected structural descriptors successfully differentiated between bitter and nonbitter peptides.
Publisher: Informa UK Limited
Date: 11-11-2020
Publisher: Pharmaceutical Society of Japan
Date: 2010
DOI: 10.1248/CPB.58.1132
Abstract: The solubility of pioglitazone hydrochloride in binary mixtures of polyethylene glycol 400 with ethanol, N-methyl-2-pyrrolidone, propylene glycol, and water at 25 degrees C are reported. The generated data are fitted to the Jouyban-Acree model and the mean relative deviations are 2.6%, 1.5%, 5.8%, and 7.4%, respectively for ethanol, N-methyl-2-pyrrolidone, propylene glycol, and water.
Publisher: No publisher found
Date: 2021
Publisher: Elsevier BV
Date: 04-2012
Publisher: Informa UK Limited
Date: 16-03-2017
Publisher: Informa UK Limited
Date: 02-08-2017
Location: United Kingdom of Great Britain and Northern Ireland
Location: Iran (Islamic Republic of)
No related grants have been discovered for Abolghasem Jouyban.