ORCID Profile
0000-0001-7522-0727
Current Organisation
Chiang Mai University Faculty of Science
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Publisher: Informa UK Limited
Date: 09-09-2016
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1AN00116G
Abstract: An ultrasensitive electrochemical biosensor based on a gold nanoparticles/graphene olypyrrole composite modified electrode and a signal lification strategy employing methylene blue is developed as a potential tool for the detection of miRNA-21.
Publisher: Elsevier BV
Date: 12-2005
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/EN05086
Abstract: Environmental Context.Effective management of eutrophication and resultant major algal blooms requires accurate assessment of the importance of internal (sediment-based) as well as external, sources of phosphorus to susceptible aquatic ecosystems. The high spatial variability in pore water filterable reactive phosphorus (FRP) necessitates extensive s ling, and rapid flow injection methods overcome many of the difficulties in maintaining s le integrity. A simple flow injection manifold has been developed to prevent major sulfide interference with FRP determination and therefore enable accurate phosphate measurements. Abstract.Simple on-line sulfide removal using potassium permanganate (KMnO4) was incorporated into a spectrophotometric flow injection (FI) system for phosphate determination using molybdenum blue with ascorbic acid as the reductant. Excess KMnO4 was reduced before the s le zone passed through the detector and the method effectively removed all sulfide interference. Without this removal, sulfide interference caused major errors in filterable reactive phosphorus (FRP) analyses. Some model organic phosphates were tested with the permanganate manifold and there was no conversion to phosphate. With the KMnO4 carrier, the calibration plot was linear over the tested range (0–1000 μg L−1 P), with a detection limit of 38 μg L−1 P. Precision was typically better than 2.5%, based on triplicate injections. FRP determinations on anoxic, estuarine pore water s les were in excellent agreement with the conventional batch method with prior acidification and sparging, but avoided s le pretreatment and the generation of toxic H2S. S les spiked with phosphate gave recoveries of 93–104%. Given the simplicity of modifying conventional FI manifolds to incorporate the improvements described here, it is recommended that all FRP measurements by FI replace water as the carrier with 0.01 M KMnO4 whenever the presence of sulfide is suspected.
Publisher: Elsevier BV
Date: 15-04-2005
DOI: 10.1016/J.TALANTA.2004.12.032
Abstract: A FI system for rapid sequential determination of dissolved reactive and organic phosphate is described. It utilizes on-line UV photo-oxidation for digestion of dissolved organic phosphate (DOP) with detection of the phosphate produced as phosphomolybdenum blue at 690 nm after reduction of phosphomolybdate with tin(II) chloride. Two injections are performed in the analysis of each s le: the first of s le solution alone enables DRP determination, while the second is of s le plus alkaline peroxydisulfate solutions, which under the photo-oxidation conditions used converts DOP to DRP. The DOP content is evaluated from the difference of the two injections. The digestion efficiency for DOP, evaluated using a range of model organic P compounds of varying stability was greater than 97%. Calibrations were linear over the range of 0.01-6.00 mg Pl(-1) for both DRP and DRP+DOP graphs, with a detection limit (3s) of 0.01 mg Pl(-1) for both species. Relative standard deviations were 0.3% (n=11, 0.50 mg Pl(-1)) for the DRP determination and 1.0% (n=11, 0.50 mg Pl(-1)) for the DRP+DOP determination. Injection throughput of 22 h(-1) was achieved. The proposed system was validated by analysis of the certified reference materials and comparison with the previous flow injection system. Additional advantage of this system is that it requires the use of only small amounts of the oxidant, with the result that nuisance gas bubble formation is correspondingly minimized.
Publisher: Elsevier BV
Date: 06-12-2002
DOI: 10.1016/S0039-9140(02)00440-X
Abstract: A simple gravitational field-flow fractionation (GrFFF) system was used for size separation of micron sized silica particles coated with hydrous iron oxide (geothite). The amount of iron on the particles was monitored either on-line by reverse-flow injection analysis (r-FIA) with chemiluminescence detection using luminol or off-line by electrothermal atomic absorption spectrophotometry (ETAAS). The combination of GrFFF with reverse FIA or with ETAAS has been demonstrated to be a cost-effective tool for size based iron speciation of particles.
Publisher: Springer Science and Business Media LLC
Date: 03-2016
Abstract: In this work, a cost-effective and simple-to-prepare label-free electrochemical immunosensor was, for the first time, fabricated by modifying high-quality graphene oxide (GPO) onto a screen-printed carbon electrode (SPCE). The anti-IgG antibody was then covalently immobilized to the carboxylic group anchoring on the surface of GPO particles. Under the optimized condition, our newly developed immunosensor selectively bound to human immunoglobulin G (IgG), a model biomarker, with high sensitivity at a limit of detection of 1.99 ng mL(-1), potentially sensitive enough for IgG detection at the pathophysiological level, and had a linear range of 2.5 to 100 ng mL(-1). The proposed immunosensor also exhibited high reproducibility and regenerability, resulting in no significant change in electrochemical signals from different replicates of the electrode, and a robust electrochemical current after being subjected to alkaline base washing with several cycles. To this end, our immunosensor demonstrates ability as a promising diagnostic tool for clinical assessment.
Publisher: The Chemical Society of Japan
Date: 15-11-2020
Publisher: The Chemical Society of Japan
Date: 05-12-2016
DOI: 10.1246/CL.160715
Publisher: Elsevier BV
Date: 06-2019
DOI: 10.1016/J.BIOELECHEM.2019.01.008
Abstract: A facile one-step electrochemical synthesis of a platinum/reduced graphene oxide oly(3-aminobenzoic acid) (Pt/rGO/P3ABA) nanocomposite film on a screen-printed carbon electrode (SPCE) and its application in the development of sensitive erometric biosensors was successfully demonstrated herein. The electropolymerization of P3ABA together with co-electrodeposition of rGO and Pt was conducted by cyclic voltammetry, as was the GO reduction to rGO. A Pt/rGO/P3ABA-modified SPCE exhibited excellent electrocatalytic oxidation towards hydrogen peroxide (H
Publisher: Elsevier BV
Date: 10-2019
Publisher: Elsevier BV
Date: 02-2020
DOI: 10.1016/J.TALANTA.2019.120389
Abstract: In this work, we developed an effective voltammetric immunosensing platform for the sensitive detection of prostate specific antigen (PSA) utilizing a graphene oxide (GO) modified screen-printed carbon electrode (SPCE) hybridized with the ex-situ prepared silver nanoparticles (AgNPs) as a probe and signal transducer. The sensing platform comprises a direct-type immunoassay involving the selective interaction of PSA with anti-PSA. The surface morphology and analytical performance of the modified SPCE were characterized through relevant instrumentations. The changes in the voltammetric reduction current of AgNPs at 0.11 V in the sensor electrode was correlated to the PSA concentration. Under optimum conditions, the fabricated immunosensor exhibited a sensitive response to PSA with a limit of detection (LOD) of 0.27 ng mL
Publisher: MDPI AG
Date: 02-02-2020
DOI: 10.3390/S20030808
Abstract: In this research work, a non-enzymatic erometric sensor for the determination of glucose was designed based on carbon nanodots (C-dots) and copper oxide (CuO) nanocomposites (CuO-C-dots). The CuO-C-dots nanocomposites were modified on the surface of a screen-printed carbon electrode (SPCE) to increase the sensitivity and selectivity of the glucose sensor. The as-synthesized materials were further analyzed for physico-chemical properties through characterization tools such as transmission electron microscopy (TEM) and Fourier-transform infrared spectroscopy (FTIR) and their electrochemical performance was also studied. The SPCE modified with CuO-C-dots possess desirable electrocatalytic properties for glucose oxidation in alkaline solutions. Moreover, the proposed sensing platform exhibited a linear range of 0.5 to 2 and 2 to 5 mM for glucose detection with high sensitivity (110 and 63.3 µA mM−1cm−2), and good selectivity and stability and could potentially serve as an effective alternative method of glucose detection.
Publisher: Elsevier BV
Date: 08-2018
Publisher: Elsevier BV
Date: 07-2020
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1AN00436K
Abstract: An electrochemical biosensor employing a gold nanoparticles/graphene quantum dots/graphene oxide composite modified electrode is developed for the multiplex detection of miRNA breast cancer biomarkers.
Publisher: Elsevier BV
Date: 15-04-2005
DOI: 10.1016/J.TALANTA.2004.12.064
Abstract: Dissolved reactive phosphorus (DRP) was determined as orthophosphate (PO(4)-P) in fresh and saline water s les by flow-injection (FI) erometry, without and with in-valve column preconcentration. Detection is based on reduction of the product formed from the reaction of DRP with acidic molybdate at a glassy carbon working electrode (GCE) at 220 mV versus the Ag/AgCl reference electrode. A 0.1M potassium chloride solution was used as both supporting electrolyte and eluent in the preconcentration system. For the FI configuration without preconcentration, a detection limit of 3.4 microg Pl(-1) and s le throughput of 70 s les h(-1) were achieved. The relative standard deviations for 50 and 500 microg Pl(-1) orthophosphate standards were 5.2 and 5.9%, respectively. By incorporating an ion exchange preconcentration column, a detection limit of 0.18 microg Pl(-1) was obtained for a 2-min preconcentration time (R.S.D.s for 0.1 and 1 microg Pl(-1) standards were 22 and 1.0%, respectively). Potential interference from silicate, sulfide, organic phosphates and sodium chloride were investigated. Both the systems were applied to the analysis of certified reference materials and water s les.
Publisher: The Chemical Society of Japan
Date: 05-06-2015
DOI: 10.1246/CL.150101
Publisher: Informa UK Limited
Date: 06-08-2017
DOI: 10.1080/21691401.2017.1360322
Abstract: This work focuses on fabricating poly(2-aminobenzylamine)-modified screen-printed carbon electrode as an electrochemical immunosensor for the label-free detection of human immunoglobulin G. To selectively detect immunoglobulin G, the anti-immunoglobulin G antibody with high affinity to immunoglobulin G was covalently linked with the amine group of poly(2-aminobenzylamine) film-deposited screen-printed carbon electrode. The selectivity for immunoglobulin G was subsequently assured by being challenged with redox-active interferences and adventitious adsorption did not significantly interfere the analyte signal. To obviate the use of costly secondary antibody, the [Fe(CN)
Publisher: Elsevier BV
Date: 12-2021
DOI: 10.1016/J.BIOELECHEM.2021.107944
Abstract: Methylene blue (MB) adsorption onto a two-dimensional molybdenum disulfide (2D MoS
Publisher: Elsevier BV
Date: 08-2017
DOI: 10.1016/J.TALANTA.2017.04.058
Abstract: Sequential injection (SI) system incorporated with erometric immunosensor was developed for sensitive determination of human immunoglobulin G (HIgG). A cost effective label-free immunosensor was fabricated by immobilizing anti-HIgG on a graphene oxide (GO) modified screen-printed carbon electrode (SPCE). The developed electrode was characterized by cyclic voltammetry(CV), scanning electron microscope(SEM), and energy dispersive spectroscopy(EDS) which confirmed the selective immunointeraction of HIgG to the anti-HIgG on the electrode, thus reduced the erometric current of [Fe(CN)
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D0AN02149K
Abstract: A novel electrochemical immunosensor for the detection of a new lung cancer biomarker based on a polyoxometalate-adsorbed poly(ethylenimine)-coated gold nanoparticle modified electrode.
Publisher: Royal Society of Chemistry (RSC)
Date: 2021
DOI: 10.1039/D1TB00940K
Abstract: A novel label-free electrochemical immunosensor is developed for the simultaneous detection of breast cancer biomarkers employing redox species-antibody-conjugated polyethyleneimine-coated AuNPs.
Publisher: Informa UK Limited
Date: 06-09-2019
Publisher: Elsevier BV
Date: 10-2020
Publisher: Elsevier BV
Date: 06-12-2002
DOI: 10.1016/S0039-9140(02)00414-9
Abstract: A reverse flow injection method (rFIA) based on the Winkler titration chemistry, is reported for the determination of dissolved oxygen (DO) in natural waters. Manganese(II) sulfate is injected into a continuously flowing stream of s le and subsequently merges with a reagent stream of sodium hydroxide and sodium iodide. Manganese(II) hydroxide that is formed reacts with DO in the s le to form an oxidized manganese hydroxyoxide floc. Addition of 10% sulfuric acid dissolves this floc, and under acidic conditions, the triiodide ion formed is detected by photometry in a flow through cell at a wavelength of 440 nm. The method is rapid (48 measurements per h), repeatable (R.S.D. ca. 3%, n=3), and has a calculated detection limit of 0.25 mg l(-1) (P=0.001). No interference from nitrite or ferrous ions was observed at concentrations typically found in natural waters. The method has been successfully applied to on-line measurement of DO in sediment respiration reactors.
No related grants have been discovered for Jaroon Jakmunee.