ORCID Profile
0000-0002-2868-5799
Current Organisation
University of Melbourne
Does something not look right? The information on this page has been harvested from data sources that may not be up to date. We continue to work with information providers to improve coverage and quality. To report an issue, use the Feedback Form.
Research Topics
In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Top 5 Research Topics
ANZSRC Field of Research (FoR)
Macromolecular and Materials Chemistry | Synthesis of Materials | Nanotechnology | Biomaterials | Biomedical Engineering | Synthesis Of Macromolecules | Catalysis and Mechanisms of Reactions | Biomaterials | Biomechanical Engineering | Organic Chemical Synthesis | Analytical Spectrometry | Physical Chemistry (Incl. Structural) | Biotechnology Not Elsewhere Classified | Sociology and Social Studies of Science and Technology | Nanomedicine | Functional Materials | Nanotechnology | Polymers and Plastics | Materials Engineering | Nanobiotechnology
ANZSRC Socio-Economic Objective (SEO)
Expanding Knowledge in the Chemical Sciences | Biological sciences | Expanding Knowledge in the Biological Sciences | Workforce Transition and Employment | Organic Industrial Chemicals (excl. Resins, Rubber and Plastics) | Chemical sciences | Physical sciences | Expanding Knowledge in the Medical and Health Sciences | Expanding Knowledge in Technology | Human Pharmaceutical Treatments (e.g. Antibiotics) | Industrial Chemicals and Related Products not elsewhere classified | Expanding Knowledge in Engineering | Prevention—biologicals (e.g. vaccines) | Diagnostics |
Related Links
Publications
Flow Cytometry: HD Flow Cytometry: An Improved Way to Quantify Cellular Interactions with Nanoparticles (Adv. Healthcare Mater. 18/2016)
Publisher: Wiley
Date: 09-2016
Polyglyoxylamides with a pH-Mediated Solubility and Depolymerization Switch
Publisher: American Chemical Society (ACS)
Date: 05-11-2021
Assembly and degradation of low-fouling click-functionalized poly(ethylene glycol)-based multilayer films and capsules
Publisher: Wiley
Date: 21-03-2011
Abstract: Nano-/micrometer-scaled films and capsules made of low-fouling materials such as poly(ethylene glycol) (PEG) are of interest for drug delivery and tissue engineering applications. Herein, the assembly and degradation of low-fouling, alkyne-functionalized PEG (PEG(Alk) ) multilayer films and capsules, which are prepared by combining layer-by-layer (LbL) assembly and click chemistry, are reported. A nonlinear, temperature-responsive PEG(Alk) is synthesized, and is then used to form hydrogen-bonded multilayers with poly(methacrylic acid) (PMA) at pH 5. The thermoresponsive behavior of PEG(Alk) is exploited to tailor film buildup by adjusting the assembly conditions. Using alkyne-azide click chemistry, PEG(Alk)/PMA multilayers are crosslinked with a bisazide linker that contains a disulfide bond, rendering these films and capsules redox-responsive. At pH 7, by disrupting the hydrogen bonding between the polymers, PEG(Alk) LbL films and PEG(Alk) -based capsules are obtained. These films exhibit specific deconstruction properties under simulated intracellular reducing conditions, but remain stable at physiological pH, suggesting potential applications in controlled drug release. The low-fouling properties of the PEG films are confirmed by incubation with human serum and a blood clot. Additionally, these capsules showed negligible toxicity to human cells.
Understanding Cell Interactions Using Modular Nanoparticle Libraries
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/CH19269
Abstract: Nanoparticle delivery systems have significant potential to facilitate the delivery of novel therapeutics, such as proteins, DNA or small molecules. However, there are multiple biological barriers that need to be overcome to deliver the cargo in an active form. These challenges include evading clearance by the reticuloendothelial system, minimising adverse immune responses, targeting specific cells and tissues, and trafficking into the right compartment of the cell. In this account, we will discuss how nanoparticle structure can be tuned to optimise biological interactions and thus improve the ability of nanoparticles to overcome these barriers. The focus of this article will be on controlling cell targeting and trafficking within a cell, e.g. endosomal escape.
Engineering cellular degradation of multilayered capsules through controlled cross-linking
Publisher: American Chemical Society (ACS)
Date: 02-11-2012
DOI: 10.1021/NN3039353
Abstract: We report a versatile approach for controlling the intracellular degradation of polymer capsules by tailoring the degree of cross-linking in the capsules. Poly(2-diisopropylaminoethyl methacrylate) capsules were assembled by the layer-by-layer technique and covalently stabilized with a redox-responsive bisazide cross-linker using click chemistry. The degree of cross-linking, determined using radiation scintillation counting, was tuned from 65% to 98% by adjusting the amount of cross-linker used to stabilize the polymer films. Transmission electron microscopy and fluorescence microscopy studies showed that the pH responsiveness of the capsules was maintained, regardless of the degree of cross-linking. Atomic force microscopy measurements on planar surfaces revealed that increasing the degree of cross-linking decreased the film roughness (from 8.7 to 1.7 nm), hence forming smoother films however the film thicknesses were not significantly altered. Cellular studies showed that the rate of intracellular degradation of the capsules could be controlled between 0 and 6 h by altering the degree of cross-linking in the polymer capsules. These studies also demonstrated that the cellular degradation of highly cross-linked capsules (>90%) was significantly retarded compared to degradation in simulated cellular conditions. This suggests that the naturally occurring cellular reducing environment is rapidly depleted, and there is a significant delay before the cells can replenish the reducing environment. The modular and versatile nature of this approach lends itself to application to a wide range of polymer carriers and thus offers significant potential for the design of polymer-based systems for drug and gene delivery.
Controlled release of DNA from poly(vinylpyrrolidone) capsules using cleavable linkers
Publisher: Elsevier BV
Date: 09-2011
DOI: 10.1016/J.BIOMATERIALS.2011.05.011
Abstract: The design of polymer carriers with tunable degradation and cargo release is fundamental for applications in drug and gene delivery. In this study, we report low-fouling poly(N-vinyl pyrrolidone) (PVPON) capsules assembled via hydrogen bonding and stabilized using covalent cross-linking. We first investigated the effects of pH and ionic strength to optimize the assembly conditions. A model therapeutic cargo (plasmid DNA) was then loaded in the capsules and used for encapsulation and release studies. Two bisazide cross-linkers that contain a disulfide bond, termed PEG₈ (poly(ethylene glycol)) and PEG(16), were employed to stabilize the multilayer films, and used to tune the degradation and cargo release behavior of the capsules in simulated cytoplasmic conditions. The results suggest that PEG₈-stabilized capsules were more efficiently cross-linked, and hence displayed higher plasmid encapsulation. Consequently, the capsules cross-linked with PEG₈ also showed a two-fold reduction in degradation rate. This ability to achieve controlled carrier degradation and cargo release makes these capsules of potential interest for drug and gene delivery.
Understanding the Polymer Rearrangement of pH-Responsive Nanoparticles
Publisher: CSIRO Publishing
Date: 23-02-2021
DOI: 10.1071/CH20331
Abstract: The use of self-assembled nanoparticles for drug delivery has received significant attention in recent years. However, the dynamic nature of self-assembled polymeric systems means there is a need to develop greater understanding of the inherent stability of these systems. In particular, understanding if these materials remain as discrete nanoparticles, or if there is dynamic exchange of material between particles is critical. Herein, we labelled pH-responsive nanoparticles with fluorescent dyes and then investigated the change in fluorescence when the particles were mixed with unlabelled nanoparticles in order to investigate their potential for polymer rearrangement. Nanoparticles were formed by the nanoprecipitation of pH-responsive poly(ethylene glycol)-block-poly(2-(diethylamino)ethyl methacrylate) (PEG-b-PDEAEMA) as the shell and poly(2-(diethylamino)ethyl methacrylate)-random-poly(2-(diisopropylamino)ethyl methacrylate) (PDEAEMA-r-PDPAEMA) as the core. The core and shell were labelled by incorporating pentafluorophenyl methacrylate (PFPMA) in core or shell respectively and then coupling with either Sulfo-cyanine5 amine or Cyanine3 amine. Exchange of material between nanoparticles was probed by tracking changes in the self-quenching of fluorescently labelled polymers in the core of the nanoparticles. The fluorescence intensity of the labelled nanoparticles was stable when mixed with unlabelled nanoparticles at physiological pH (pH 7.4), suggesting there is limited migration of polymers between particles in this system. This study provides important insights into the use of non-crosslinked nanoparticles under biologically relevant conditions.
Challenges facing colloidal delivery systems: From synthesis to the clinic
Publisher: Elsevier BV
Date: 06-2011
Controlling Endosomal Escape Using pH-Responsive Nanoparticles with Tunable Disassembly
Publisher: American Chemical Society (ACS)
Date: 05-06-2018
Bio-click chemistry: enzymatic functionalization of PEGylated capsules for targeting applications
Publisher: Wiley
Date: 28-06-2012
Abstract: All sorted: The enzyme Sortase A was used to catalyze functionalization of PEGylated capsules with an activation-specific anti-platelet single-chain antibody (scFv). This enzymatic method allows fast, covalent, and site-directed functionalization of delivery vehicles under mild conditions. Activation-specific anti-platelet scFv-coated PEGylated capsules exhibited a high level of selective binding to thrombi, thus suggesting their potential for thrombosis therapy.
The generic enhancement of photochromic dye switching speeds in a rigid polymer matrix
Publisher: Springer Science and Business Media LLC
Date: 06-02-2005
DOI: 10.1038/NMAT1326
Abstract: The switching or isomerization speed of photochromic dyes in a rigid polymeric matrix (such as an ophthalmic lens) is generally significantly slower than that observed in the mobile environment of a solution. Here we describe that the attachment of flexible oligomers having a low glass-transition temperature-such as poly(dimethylsiloxane)-to photochromic dyes greatly increases their switching speeds in a rigid polymer matrix. The greatest impact was observed in the thermal fade parameters T(1/2) and T(3/4)-the times it takes for the optical density to reduce by half and three quarters of the initial optical density of the coloured state-which were reduced by 40-95% and 60-99% respectively for spirooxazines, chromenes and an azo dye in a host polymer with a glass-transition temperature of 120 degrees C. The method does not alter the electronic nature of the dyes but simply protects them from the host matrix and provides greater molecular mobility for the switching process. In addition to ophthalmic lenses, the generic nature of the method may find further utility in data recording or optical switching.
Endocytic Capsule Sensors for Probing Cellular Internalization
Publisher: Wiley
Date: 04-04-2014
Abstract: A new class of polymer capsules with an in-built endocytic pH-coupled fluorescence switch is reported. These capsules display reversible "on/off" fluorescence in response to cellular pH variations. Using this system, the high-throughput quantification between surface-bound and internalized capsules is demonstrated. This system allows a fundamental study of the interaction between nanoengineered materials and biological systems at a cellular level.
Modular Assembly of Layer-by-Layer Capsules with Tailored Degradation Profiles †
Publisher: American Chemical Society (ACS)
Date: 03-12-2011
DOI: 10.1021/LA104232R
Abstract: Herein we report the preparation of layer-by-layer (LbL) assembled, biodegradable, covalently stabilized capsules with tunable degradation properties. Poly(L-glutamic acid) modified with alkyne moieties (PGA(Alk)) was alternately assembled with poly(N-vinyl pyrrolidone) (PVPON) on silica particles via hydrogen-bonding. The films were cross-linked with a bis-azide linker, followed by removal of the sacrificial template and PVPON at physiological pH through hydrogen bond disruption, yielding one-component PGA(Alk) capsules. To control the kinetics and location of capsule degradation, a number of approaches were investigated. First, a degradable bis-azide cross-linker was incorporated into the inherently enzymatically degradable capsules. Second, we assembled low-fouling capsules composed of nondegradable poly(N-vinyl pyrrolidone-ran-propargyl acrylate) (PVPON(Alk)) via hydrogen bonding with poly(methacrylic acid) (PMA) and combined this with the aforementioned system (PGA(Alk)/PVPON) to produce stratified hybrid capsules. The degradation profiles of these stratified capsules can be closely controlled by the number as well as the position of nondegradable barrier layers in the systems. The facile tailoring of the degradation kinetics makes this stratified LbL approach promising for the design of tailored drug-delivery vehicles.
Dopamine-Mediated Continuous Assembly of Biodegradable Capsules
Publisher: American Chemical Society (ACS)
Date: 17-06-2011
DOI: 10.1021/CM201390E
Biomedical Applications: Endocytic pH‐Triggered Degradation of Nanoengineered Multilayer Capsules (Adv. Mater. 12/2014)
Publisher: Wiley
Date: 03-2014
Lewis Base Catalyzed Synthesis of Sulfur Heterocycles via the C1‐Pyridinium Enolate
Publisher: Wiley
Date: 11-07-2022
Abstract: While the addition of C1‐Lewis base enolates to carbonyls and related structures are well established, the related addition to thiocarbonyls compounds are unknown. Herein, we report a reaction cascade in which a C1‐pyridinium enolate undergos addition to dithioesters, trithiocarbonates and xanthates. The reaction provides access to a range of dihydrothiophenes and dihydrothiopyrans (28‐ex les). Mechanistic investigations, including isolation of intermediates, electronic correlation, and kinetic isotope effect studies support the viability of an activated acid intermediate giving rise to the C1‐pyridinium enolate which undergoes turnover limiting cyclization. Subsequent formation of a β‐thiolactone regenerates the catalyst with loss of carbon oxysulfide providing the observed products.
Peptide-functionalized, low-biofouling click multilayers for promoting cell adhesion and growth
Publisher: Wiley
Date: 19-02-2009
Surface Click Chemistry on Brominated Plasma Polymer Thin Films
Publisher: American Chemical Society (ACS)
Date: 10-11-2010
DOI: 10.1021/LA9031688
Abstract: A brominated plasma polymer (BrPP) thin film was fabricated on a variety of substrate surfaces (silicon wafers, glass, gold, and polymers) via the radio frequency glow discharge of 1-bromopropane. This BrPP thin film was highly adherent and stable and was found to be a useful platform for secondary reactions, leading to surfaces with specific chemical functionalities. Following nucleophilic exchange, an azide-functionalized PP thin film was prepared that was reactive toward two different alkynes via the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, a paradigm of "click" chemistry. "Click" microcontact printing (microCP) of a fluorescent alkyne was also successfully carried out, demonstrating the versatility and functionality of this new class of reactive thin film plasma polymer coatings.
The Endosomal Escape of Nanoparticles: Toward More Efficient Cellular Delivery
Publisher: American Chemical Society (ACS)
Date: 19-11-2019
DOI: 10.1021/ACS.BIOCONJCHEM.8B00732
Abstract: Many emerging therapies rely on the delivery of biological cargo into the cytosol. Nanoparticle delivery systems hold great potential to deliver these therapeutics but are hindered by entrapment and subsequent degradation in acidic compartments of the endo/lysosomal pathway. Engineering polymeric delivery systems that are able to escape the endosome has significant potential to address this issue. However, the development of safe and effective delivery systems that can reliably deliver cargo to the cytosol is still a challenge. Greater understanding of the properties that govern endosomal escape and how it can be quantified is important for the development of more efficient nanoparticle delivery systems. This Topical Review highlights the current understanding of the mechanisms by which nanoparticles escape the endosome, and the emerging techniques to improve the quantification of endosomal escape.
Immobilization and Intracellular Delivery of an Anticancer Drug Using Mussel-Inspired Polydopamine Capsules
Publisher: American Chemical Society (ACS)
Date: 13-07-2012
DOI: 10.1021/BM300835R
Abstract: We report a facile approach to immobilize pH-cleavable polymer-drug conjugates in mussel-inspired polydopamine (PDA) capsules for intracellular drug delivery. Our design takes advantage of the facile PDA coating to form capsules, the chemical reactivity of PDA films, and the acid-labile groups in polymer side chains for sustained pH-induced drug release. The anticancer drug doxorubicin (Dox) was conjugated to thiolated poly(methacrylic acid) (PMA(SH)) with a pH-cleavable hydrazone bond, and then immobilized in PDA capsules via robust thiol-catechol reactions between the polymer-drug conjugate and capsule walls. The loaded Dox showed limited release at physiological pH but significant release (over 85%) at endosomal/lysosomal pH. Cell viability assays showed that Dox-loaded PDA capsules enhanced the efficacy of eradicating HeLa cancer cells compared with free drug under the same assay conditions. The reported method provides a new platform for the application of stimuli-responsive PDA capsules as drug delivery systems.
Nanoengineered Films via Surface‐Confined Continuous Assembly of Polymers
Publisher: Wiley
Date: 24-08-2011
Affirmative recruitment of women in STEM: a case study
Publisher: Informa UK Limited
Date: 16-12-2022
Multicompartment Polymeric Nanocarriers for Biomedical Applications
Publisher: Wiley
Date: 19-07-2020
Tuning particle biodegradation through polymer-peptide blend composition
Publisher: American Chemical Society (ACS)
Date: 31-10-2014
DOI: 10.1021/BM5012272
Abstract: We report the preparation of polymer-peptide blend replica particles via the mesoporous silica (MS) templated assembly of poly(ethylene glycol)-block-poly(2-diisopropylaminoethyl methacrylate-co-2-(2-(2-(prop-2-ynyloxy)ethoxy)ethoxy)ethyl methacrylate) (PEG45-b-P(DPA55-co-PgTEGMA4)) and poly(l-histidine) (PHis). PEG45-b-P(DPA55-co-PgTEGMA4) was synthesized by atom transfer radical polymerization (ATRP), and was coinfiltrated with PHis into poly(methacrylic acid) (PMA)-coated MS particles assembled from different peptide-to-polymer ratios (1:1, 1:5, 1:10, or 1:15). Subsequent removal of the sacrificial templates and PMA resulted in monodisperse, colloidally stable, noncovalently cross-linked polymer-peptide blend replica particles that were stabilized by a combination of hydrophobic interactions between the PDPA and the PHis, hydrogen bonding between the PEG and PHis backbone, and π-π stacking of the imidazole rings of PHis side chains at physiological pH (pH ∼ 7.4). The synergistic charge-switchable properties of PDPA and PHis, and the enzymatic degradability of PHis, make these particles responsive to pH and enzymes. In vitro studies, in simulated endosomal conditions and inside cells, demonstrated that particle degradation kinetics could be engineered (from 2 to 8 h inside dendritic cells) based on simple adjustment of the peptide-to-polymer ratio used.
Poly(vinylpyrrolidone) for bioconjugation and surface ligand immobilization
Publisher: American Chemical Society (ACS)
Date: 23-08-2007
DOI: 10.1021/BM700498J
Abstract: Poly(vinylpyrrolidone) (PVP), a nonionic and nontoxic polymer with antifouling properties, has been synthesized via RAFT polymerization to obtain thiol-terminated PVP. We demonstrate that when the polymer is adsorbed onto the surface of colloidal silica particles, the terminal thiol groups of PVP remain accessible for chemical modification and lend themselves to the immobilization of ligands. We show that ligand attachment onto the surface via conjugation to PVP is reversible, as the polymer can be desorbed from the surface for conjugate and surface recovery. We present the conjugation of a model peptide and an oligonucleotide to PVP via the polymer terminal thiol and demonstrate that conjugates remain functional in molecular recognition assay. The developed technique offers a novel method to functionalize low-fouling surfaces for a variety of biomedical applications and presents opportunities to use PVP as a macromolecular drug carrier.
Tuning the Properties of Layer-by-Layer Assembled Poly(acrylic acid) Click Films and Capsules
Publisher: American Chemical Society (ACS)
Date: 04-02-2011
DOI: 10.1021/MA102593K
Ultrathin, responsive polymer click capsules
Publisher: American Chemical Society (ACS)
Date: 26-05-2007
DOI: 10.1021/NL070698F
Abstract: We report a general click chemistry approach for the layer-by-layer assembly of ultrathin, polymer films on particles and the subsequent formation of polymer click capsules (CCs). Poly(acrylic acid) copolymers, synthesized with a minor component of either alkyne (PAA-Alk) or azide (PAA-Az) functionality, were alternately assembled on silica particles. The (PAA-Az/PAA-Alk)-coated particles were subsequently functionalized by exploiting the free alkyne click moieties present in the film upon exposure to an azide-modified rhodamine dye. Further, PAA CCs, obtained following removal of the silica particle template, were shown to exhibit pH-responsive behavior. This was demonstrated by reversible size changes of the CCs upon cycling between basic and acidic solutions. Polymer CCs are anticipated to find applications in various fields, including drug delivery and sensing.
Multifunctional Thrombin‐Activatable Polymer Capsules for Specific Targeting to Activated Platelets
Publisher: Wiley
Date: 03-08-2015
Abstract: Smart poly(2-oxazoline) (POx)-based multifunctional polymer capsules that specifically target glycoprotein (GP) IIb/IIIa on the surface of activated platelets are degraded by the serine protease thrombin and release the urokinase plasminogen activator loaded into the polymer capsules, only in the area of acute thrombosis.
Engineering particles for therapeutic delivery: Prospects and challenges
Publisher: American Chemical Society (ACS)
Date: 30-04-2012
DOI: 10.1021/NN3016162
Abstract: Nanoengineered particles that can facilitate drug formulation and passively target tumors have reached the clinic in recent years. These early successes have driven a new wave of significant innovation in the generation of advanced particles. Recent developments in enabling technologies and chemistries have led to control over key particle properties, including surface functionality, size, shape, and rigidity. Combining these advances with the rapid developments in the discovery of many disease-related characteristics now offers new opportunities for improving particle specificity for targeted therapy. In this Perspective, we summarize recent progress in particle-based therapeutic delivery and discuss important concepts in particle design and biological barriers for developing the next generation of particles.
Toward therapeutic delivery with layer-by-layer engineered particles
Publisher: American Chemical Society (ACS)
Date: 25-05-2011
DOI: 10.1021/NN201793F
Abstract: Layer-by-layer (LbL)-engineered particles have recently emerged as a promising class of materials for applications in biomedicine, with studies progressing from in vitro to in vivo. The versatility of LbL assembly coupled with particle templating has led to engineered particles with specific properties (e.g., stimuli-responsive, high cargo encapsulation efficiency, targeting), thus offering new opportunities in targeted and triggered therapeutic release. This Perspective highlights an important development by Poon et al. on tumor targeting in vivo using LbL-engineered nanoparticles containing a pH-responsive poly(ethylene glycol) (PEG) surface layer. Further, we summarize recent progress in the application of LbL particles in the fields of drug, gene, and vaccine delivery and cancer imaging. Finally, we explore future directions in this field, focusing on the biological processing of LbL-assembled particles.
Self-Immolative Polymer Nanoparticles with Precise and Controllable pH-Dependent Degradation
Publisher: American Chemical Society (ACS)
Date: 14-09-2023
Photoinitiated Alkyne-Azide Click and Radical Cross-Linking Reactions for the Patterning of PEG Hydrogels
Publisher: American Chemical Society (ACS)
Date: 14-02-2012
DOI: 10.1021/BM201802W
Abstract: The photolithographical patterning of hydrogels based solely on the surface immobilization and cross-linking of alkyne-functionalized poly(ethylene glycol) (PEG-tetraalkyne) is described. Photogenerated radicals as well as UV absorption by a copper chelating ligand result in the photochemical redox reduction of Cu(II) to Cu(I). This catalyzes the alkyne-azide click reaction to graft the hydrogels onto an azide-functionalized plasma polymer (N(3)PP) film. The photogenerated radicals were also able to abstract hydrogen atoms from PEG-tetraalkyne to form poly(α-alkoxy) radicals. These radicals can initiate cross-linking by addition to the alkynes and intermolecular recombination to form the PEG hydrogels. Spatially controlling the two photoinitiated reactions by UV exposure through a photomask leads to surface patterned hydrogels, with thicknesses that were tunable from tens to several hundreds of nanometers. The patterned PEG hydrogels (ca. 60 μm wide lines) were capable of resisting the attachment of L929 mouse fibroblast cells, resulting in surfaces with spatially controlled cell attachment. The patterned hydrogel surface also demonstrated spatially resolved chemical functionality, as postsynthetic modification of the hydrogels was successfully carried out with azide-functionalized fluorescent dyes via subsequent alkyne-azide click reactions.
Understanding the Biological Interactions of pH‐Swellable Nanoparticles
Publisher: Wiley
Date: 04-03-2022
Abstract: pH‐responsive nanoparticles have generated significant interest for use as drug delivery systems due to their potential for inducible release at low pH. The pH variation from the bloodstream (pH 7.4) to intracellular compartments of cells called endosomes/lysosomes (pH 5.0) has been of particular interest. However, one of the limitations with nanoparticle delivery systems is the inability to migrate out of these compartments to the cytosol or other organelles, via a process termed endosomal escape. Previous studies have postulated that pH‐responsive nanoparticles can facilitate endosomal escape through a range of mechanisms including membrane interaction, pH‐induced swelling, and the proton‐sponge effect. In this study, a series of pH‐swellable nanoparticles (85–100 nm) are designed and their impact on biological interactions, particularly endosomal escape, are investigated. The particles exhibit tunable pH‐induced swelling (from 120% to 200%) and have good buffering capacity. The cellular association is studied using flow cytometry and endosomal escape is determined using a calcein leakage assay. Interestingly, no endosomal escape with all nanoparticle formulations is found, which suggests there are limitations with both the proton‐sponge effect and pH‐induced swelling mechanism as the primary methods for inducing endosomal escape.
Engineered Polymeric Materials for Biological Applications: Overcoming Challenges of the Bio–Nano Interface
Publisher: MDPI AG
Date: 02-09-2019
Abstract: Nanomedicine has generated significant interest as an alternative to conventional cancertherapy due to the ability for nanoparticles to tune cargo release. However, while nanoparticletechnology has promised significant benefit, there are still limited ex les of nanoparticles inclinical practice. The low translational success of nanoparticle research is due to the series ofbiological roadblocks that nanoparticles must migrate to be effective, including blood and plasmainteractions, clearance, extravasation, and tumor penetration, through to cellular targeting,internalization, and endosomal escape. It is important to consider these roadblocks holistically inorder to design more effective delivery systems. This perspective will discuss how nanoparticlescan be designed to migrate each of these biological challenges and thus improve nanoparticledelivery systems in the future. In this review, we have limited the literature discussed to studiesinvestigating the impact of polymer nanoparticle structure or composition on therapeutic deliveryand associated advancements. The focus of this review is to highlight the impact of nanoparticlecharacteristics on the interaction with different biological barriers. More specific studies/reviewshave been referenced where possible.
Engineering enzyme-cleavable hybrid click capsules with a pH-sheddable coating for intracellular degradation
Publisher: Wiley
Date: 10-07-2014
Abstract: The engineering of layer-by-layer (LbL) hybrid click capsules that are responsive to biological stimuli is reported. The capsules comprise a pH-sheddable, non cross-linked outer coating that protects enzyme-cleavable inner layers. Upon cellular uptake, the outer coating is released and the capsules are enzymatically degraded. In vitro cell degradation results in rapid capsule degradation (10 min) upon cellular internalization.
Polyelectrolyte blend multilayers: A versatile route to engineering interfaces and films
Publisher: Wiley
Date: 11-12-2008
Correction: Engineered hydrogen-bonded polymer multilayers: from assembly to biomedical applications
Publisher: Royal Society of Chemistry (RSC)
Date: 2018
DOI: 10.1039/C8CS90110D
Abstract: Correction for ‘Engineered hydrogen-bonded polymer multilayers: from assembly to biomedical applications’ by Georgina K. Such et al. , Chem. Soc. Rev. , 2011, 40 , 19–29.
Reaction Vessels Assembled by the Sequential Adsorption of Polymers
Publisher: Springer Berlin Heidelberg
Date: 2010
DOI: 10.1007/12_2009_44
Acid-Responsive Poly(glyoxylate) Self-Immolative Star Polymers
Publisher: American Chemical Society (ACS)
Date: 19-08-2021
Click poly(ethylene glycol) multilayers on RO membranes: Fouling reduction and membrane characterization
Publisher: Elsevier BV
Date: 08-2012
Charge-Shifting Click Capsules with Dual-Responsive Cargo Release Mechanisms
Publisher: Wiley
Date: 09-08-2011
Low-Fouling, Biofunctionalized, and Biodegradable Click Capsules
Publisher: American Chemical Society (ACS)
Date: 08-11-2008
DOI: 10.1021/BM800794W
Abstract: We report the synthesis of covalently stabilized hollow capsules from biodegradable materials using a combination of click chemistry and layer-by-layer (LbL) assembly. The biodegradable polymers poly(L-lysine) (PLL) and poly(L-glutamic acid) (PGA) were modified with alkyne and azide moieties. Linear film buildup was observed for both materials on planar surfaces and colloidal silica templates. A variation of the assembly conditions, such as an increase in the salt concentration and variations in pH, was shown to increase the in idual layer thickness by almost 200%. The biodegradable click capsules were analyzed with optical microscopy, scanning electron microscopy (SEM), and atomic force microscopy (AFM). Capsules were uniform in size and had a regular, spherical shape. They were found to be stable between pH 2 and 11 and showed reversible, pH-responsive shrinking/swelling behavior. We also show that covalently stabilized PLL films can be postfunctionalized by depositing a monolayer of heterobifunctional poly(ethylene glycol) (PEG), which provides low-fouling properties and simultaneously enhances specific protein binding. The responsive, biodegradable click films reported herein are promising for a range of applications in the biomedical field.
New Insights into the Substrate-Plasma Polymer Interface
Publisher: American Chemical Society (ACS)
Date: 04-05-2011
DOI: 10.1021/JP200864K
Abstract: We describe a new method to characterize the underside (substrate interface) of plasma polymer (PP) thin films via their simple delamination from a sodium chloride single crystal substrate. By depositing the PP film onto an ionic bonded surface such as a sodium chloride crystal, the PP films investigated were easily delaminated from the substrate. Two plasma polymer films deposited from 1-bromopropane (BrPP) and allylamine (AAPP) were used to exemplify this new technique. The top- and underside (substrate-plasma polymer interface) of the films were examined by X-ray photoelectron spectroscopy (XPS) and synchrotron-based near edge X-ray adsorption fine structure (NEXAFS) spectroscopy. The results demonstrate that both films exhibit heterogeneous film structures with their chemical composition and levels of unsaturated species. The underside of both the BrPP and the AAPP films exhibited higher concentrations of oxygen, while their topsides contained higher levels of unsaturated species. These results provide useful insights into the BrPP and AAPP film formation and the chemistry. The delamination technique provides a simple method to analyze the early stages of film chemistry for plasma polymer thin films. Furthermore, this approach opens new opportunities for additional studies on the mechanisms and fundamentals of plasma polymer thin film formation with various monomers.
Biodegradable Click Capsules with Engineered Drug-Loaded Multilayers
Publisher: American Chemical Society (ACS)
Date: 04-03-2010
DOI: 10.1021/NN9014278
Abstract: We report the modular assembly of a polymer-drug conjugate into covalently stabilized, responsive, biodegradable, and drug-loaded capsules with control over drug dose and position in the multilayer film. The cancer therapeutic, doxorubicin hydrochloride (DOX), was conjugated to alkyne-functionalized poly(l-glutamic acid) (PGA(Alk)) via amide bond formation. PGA(Alk) and PGA(Alk+DOX) were assembled via hydrogen bonding with poly(N-vinyl pyrrolidone) (PVPON) on planar and colloidal silica templates. The films were subsequently covalently stabilized using diazide cross-linkers, and PVPON was released from the multilayers by altering the solution pH to disrupt hydrogen bonding. After removal of the sacrificial template, single-component PGA(Alk) capsules were obtained and analyzed by optical microscopy, transmission electron microscopy, and atomic force microscopy. The PGA(Alk) capsules were stable in the pH range between 2 and 11 and exhibited reversible swelling/shrinking behavior. PGA(Alk+DOX) was assembled to form drug-loaded polymer capsules with control over drug dose and position in the multilayer system (e.g., DOX in every layer or exclusively in layer 3). The drug-loaded capsules could be degraded enzymatically, resulting in the sustained release of active DOX over approximately 2 h. Cellular uptake studies demonstrate that the viability of cells incubated with DOX-loaded PGA(Alk) capsules significantly decreased. The general applicability of this modular approach, in terms of incorporation of polymer-drug conjugates in other click multilayer systems, was also demonstrated. Biodegradable click capsules with drug-loaded multilayers are promising candidates as carrier systems for biomedical applications.
Peptide-Tunable Drug Cytotoxicity via One-Step Assembled Polymer Nanoparticles
Publisher: Wiley
Date: 27-12-2014
Abstract: A novel class of nanoparticles is developed for the co-delivery of a short cell penetrating peptide and a chemotherapeutic drug to achieve enhanced cytotoxicity. Tunable cytotoxicity is achieved through non-toxic peptide-facilitated gating. The strategy relies on a one-step blending process from polymer building blocks to form monodisperse, PEGylated particles that are sensitive to cellular pH variations. By varying the amount of peptide loading, the chemotherapeutic effects can be enhanced by up to 30-fold.
Nanoescapology: progress toward understanding the endosomal escape of polymeric nanoparticles
Publisher: Wiley
Date: 03-02-2017
DOI: 10.1002/WNAN.1452
Abstract: Using nanoparticles to deliver drugs to cells has the potential to revolutionize the treatment of many diseases, including HIV , cancer, and diabetes. One of the major challenges facing this field is controlling where the drug is trafficked once the nanoparticle is taken up into the cell. In particular, if drugs remain localized in an endosomal or lysosomal compartment, the therapeutic can be rendered completely ineffective. To ensure the design of more effective delivery systems we must first develop a better understanding of how nanoparticles and their cargo are trafficked inside cells. This needs to be combined with an understanding of what characteristics are required for nanoparticles to achieve endosomal escape, along with methods to detect endosomal escape effectively. This review is focused into three sections: first, an introduction to the mechanisms governing internalization and trafficking in cells, second, a discussion of methods to detect endosomal escape, and finally, recent advances in controlling endosomal escape from polymer‐ and lipid‐based nanoparticles, with a focus on engineering materials to promote endosomal escape. WIREs Nanomed Nanobiotechnol 2017, 9:e1452. doi: 10.1002/wnan.1452 This article is categorized under: Nanotechnology Approaches to Biology Nanoscale Systems in Biology
Limitations with solvent exchange methods for synthesis of colloidal fullerenes
Publisher: Elsevier BV
Date: 02-2017
Self-assembling dual component nanoparticles with endosomal escape capability
Publisher: Royal Society of Chemistry (RSC)
Date: 2015
DOI: 10.1039/C5SM00082C
Abstract: This work reports a modular nanoparticle system engineered to undergo disassembly within a biologically relevant pH range. These nanoparticles demonstrate endosomal escape, making them attractive for biomedical applications.
Synthesis and functionalization of nanoengineered materials using click chemistry
Publisher: Elsevier BV
Date: 07-2012
HD Flow Cytometry: An Improved Way to Quantify Cellular Interactions with Nanoparticles
Publisher: Wiley
Date: 05-07-2016
Abstract: Histogram deconvolution flow cytometry enables improved quantification of nanomaterial-cell interactions. The algorithm identifies the positive cells in highly overlapped populations and calculates the fluorescence intensity of the positive population. This technique performs better than commercially available methods with the additional benefit of visualizing the output.
Quantifying the Endosomal Escape of pH-Responsive Nanoparticles Using the Split Luciferase Endosomal Escape Quantification Assay
Publisher: American Chemical Society (ACS)
Date: 29-12-2021
Abstract: All nanoparticles have the potential to revolutionize the delivery of therapeutic cargo such as peptides, proteins, and RNA. However, effective cytosolic delivery of cargo from nanoparticles represents a significant challenge in the design of more efficient drug delivery vehicles. Recently, research has centered on designing nanoparticles with the capacity to escape endosomes by responding to biological stimuli such as changes in pH, which occur when nanoparticles are internalized into the endo-/lysosomal pathway. Current endosomal escape assays rely on indirect measurements and yield little quantitative information, which hinders the design of more efficient drug delivery vehicles. Therefore, we adapted the highly sensitive split luciferase endosomal escape quantification (SLEEQ) assay to better understand nanoparticle-induced endosomal escape. We applied SLEEQ to evaluate the endosomal escape behavior of two pH-responsive nanoparticles: the first with a poly(2-diisopropylamino ethyl methacrylate) (PDPAEMA) core and the second with 1:1 ratio of poly(2-diethylamino ethyl methacrylate) (PDEAEMA) and PDPAEMA. SLEEQ directly measured the cytosolic delivery and showed that engineering the nanoparticle disassembly pH could improve the endosomal escape efficiency by fivefold. SLEEQ is a versatile assay that can be used for a wide range of nanomaterials and will improve the development of drug delivery vehicles in the future.
pH-Responsive Polymer Nanoparticles for Drug Delivery
Publisher: Wiley
Date: 05-03-2019
Abstract: Stimuli-responsive nanoparticles have the potential to improve the delivery of therapeutics to a specific cell or region within the body. There are many stimuli that have shown potential for specific release of cargo, including variation of pH, redox potential, or the presence of enzymes. pH variation has generated significant interest for the synthesis of stimuli-responsive nanoparticles because nanoparticles are internalized into cells via vesicles that are acidified. Additionally, the tumor microenvironment is known to have a lower pH than the surrounding tissue. In this review, different strategies to design pH-responsive nanoparticles are discussed, focusing on the use of charge-shifting polymers, acid labile linkages, and crosslinking.
Controlling endosomal escape using nanoparticle composition: Current progress and future perspectives
Publisher: Future Medicine Ltd
Date: 2019
Abstract: Polymer nanoparticles offer significant benefits for improving delivery of biological therapeutics such as DNA and proteins, as they allow the cargo to be protected until it is delivered to a target cell. However, there are still challenges with achieving efficient delivery to the optimal cellular region. One significant roadblock is escape of nanoparticles from within the endosomal/lysosomal compartments into the cytosol. Here, we review the recent advances in understanding endosomal escape of polymer nanoparticles. We also discuss the current progress on investigating how nanoparticle structure can control endosomal escape. It is important to understand the fundamental biological processes that govern endosomal escape in order to design more effective therapeutic delivery systems.
Tailoring Photochromic Performance of Polymer-Dye Conjugates Using Living Radical Polymerization (ATRP)
Publisher: Informa UK Limited
Date: 05-2005
The Use of Block Copolymers to Systematically Modify Photochromic Behavior
Publisher: American Chemical Society (ACS)
Date: 12-2006
DOI: 10.1021/MA061674I
Targeting of cancer cells using click-functionalized polymer capsules
Publisher: American Chemical Society (ACS)
Date: 26-10-2010
DOI: 10.1021/JA106405C
Abstract: Targeted delivery of drugs to specific cells allows a high therapeutic dose to be delivered to the target site with minimal harmful side effects. Combining targeting molecules with nanoengineered drug carriers, such as polymer capsules, micelles and polymersomes, has significant potential to improve the therapeutic delivery and index of a range of drugs. We present a general approach for functionalization of low-fouling, nanoengineered polymer capsules with antibodies using click chemistry. We demonstrate that antibody (Ab)-functionalized capsules specifically bind to colorectal cancer cells even when the target cells constitute less than 0.1% of the total cell population. This precise targeting offers promise for drug delivery applications.
Low-fouling poly(N-vinyl pyrrolidone) capsules with engineered degradable properties
Publisher: American Chemical Society (ACS)
Date: 09-2009
DOI: 10.1021/BM900673M
Abstract: We report the assembly of low-fouling polymer capsules with engineered deconstruction properties by using a combination of layer-by-layer (LbL) assembly and click chemistry. Preformed, hydrogen-bonded multilayers of alkyne-functionalized poly(N-vinyl pyrrolidone) (PVPON(Alk)) and poly(methacrylic acid) (PMA) assembled at pH 4 on silica particles were cross-linked with a bisazide linker (containing a disulfide link) through alkyne-azide click chemistry. Following dissolution of the silica template particles, and altering the solution pH to 7.2 to disrupt hydrogen bonding between PVPON(Alk) and PMA to effect removal of PMA, stable, cross-linked PVPON capsules were obtained. The presence of the disulfide bond in the bisazide linker endowed the PVPON capsules with degradable characteristics under model intracellular conditions. The capsules deconstructed within 4 h in the presence of 5 mM glutathione. The cross-linked PVPON(Alk) multilayers (assembled on silica particles) were low-fouling to a range of proteins, including fibrinogen, lysozyme, immunoglobulin G, and bovine serum albumin. Further, MTT assays showed that the PVPON capsules had no effect on the proliferation of cells from a human colon cancer cell line (LIM1899), indicating negligible cytotoxicity toward the LIM1899 cells. The low-fouling, degradable, and low cytotoxicity characteristics of the PVPON capsules makes them attractive as a platform for the development of advanced therapeutic delivery systems.
Particle generation, functionalization and sortase A-mediated modification with targeting of single-chain antibodies for diagnostic and therapeutic use
Publisher: Springer Science and Business Media LLC
Date: 11-12-2015
Abstract: Antibody fusion to nonprotein materials such as contrast agents or radio-tracers, nano- or microparticles or small-molecule drugs is attracting major interest for molecular imaging and drug delivery. Nondirected bioconjugation techniques may impair antibody affinity, result in lower amounts of functional antibodies and generate multicomponent mixtures. We present a detailed protocol for the enzymatic bioconjugation of small recombinant antibodies to imaging particles, and we also describe the generation of and conjugation to a low-fouling capsule assembled for drug delivery from PEG and PVPON (poly(N-vinylpyrrolidone) by a layer-by-layer (LbL) technique. The single-chain variable fragment (scFv) is equipped with a short C-terminal LPETG tag and the fusion partners are functionalized with an N-terminal GGG nucleophilic group for sortase A conjugation. The LbL capsules are assembled through hydrogen bonding by depositing alkyne-modified poly(vinylpyrrolidone) and poly(methacrylic acid) layers on silica particles, followed by depositing alkyne-modified PEG. The generation of the antibodies and LbL capsules takes ∼1-2 weeks each. The conjugation and functional testing takes another 3-4 d.
Interfacing materials science and biology for drug carrier design
Publisher: Wiley
Date: 26-02-2015
Abstract: Over the last ten years, there has been considerable research interest in the development of polymeric carriers for biomedicine. Such delivery systems have the potential to significantly reduce side effects and increase the bioavailability of poorly soluble therapeutics. The design of carriers has relied on harnessing specific variations in biological conditions, such as pH or redox potential, and more recently, by incorporating specific peptide cleavage sites for enzymatic hydrolysis. Although much progress has been made in this field, the specificity of polymeric carriers is still limited when compared with their biological counterparts. To synthesize the next generation of carriers, it is important to consider the biological rationale for materials design. This requires a detailed understanding of the cellular microenvironments and how these can be harnessed for specific applications. In this review, several important physiological cues in the cellular microenvironments are outlined, with a focus on changes in pH, redox potential, and the types of enzymes present in specific regions. Furthermore, recent studies that use such biologically inspired triggers to design polymeric carriers are highlighted, focusing on applications in the field of therapeutic delivery.
Mechanically tunable, self-adjuvanting nanoengineered polypeptide particles
Publisher: Wiley
Date: 10-05-2013
Abstract: DNA-loaded polypeptide particles are prepared via templated assembly of mesoporous silica for the delivery of adjuvants. The elasticity and cargo-loading capacity of the obtained particles can be tuned by the amount of cross-linker used to stabilize the polypeptide particles. The use of polypeptide particles as biocarriers provides a promising method for vaccine delivery.
The potential of nanoparticle vaccines as a treatment for cancer
Publisher: Elsevier BV
Date: 06-2018
DOI: 10.1016/J.MOLIMM.2017.12.022
Abstract: A complex and multifaceted relationship exists between cancer and the immune system. Advances in our understanding of this relationship have resulted in significant clinical attention in the possibilities of cancer immunotherapy. Harnessing the immune system's potent and selective destructive capability is a major focus of attempts to treat cancer. Despite significant progress in the field, cancer therapy still remains significantly deficient, with cancer being one of the largest contributors to morbidity and mortality in the developed world. It is evident that the design of new treatment regimes is required to exploit cancer immunotherapy. Herein we review the potential for nanotechnology to overcome the challenges that have limited the more widespread implementation of immunotherapy to cancer treatment.
Engineered hydrogen-bonded polymer multilayers: From assembly to biomedical applications
Publisher: Royal Society of Chemistry (RSC)
Date: 2011
DOI: 10.1039/C0CS00001A
Abstract: In this tutorial review , developments in hydrogen-bonded LbL materials are discussed, with an emphasis on loading and release of cargo for biomedical applications.
Control of Photochromism through Local Environment Effects Using Living Radical Polymerization (ATRP)
Publisher: American Chemical Society (ACS)
Date: 25-11-2004
DOI: 10.1021/MA048627F
Impact of the Core Architecture of Dual pH-Responsive Polymer Nanoparticles on Intracellular Delivery of Doxorubicin
Publisher: American Chemical Society (ACS)
Date: 05-06-2023
Probing Endosomal Escape Using pHlexi Nanoparticles
Publisher: Wiley
Date: 27-10-2017
Abstract: The effective escape of nanocarriers from endosomal compartments of the cell remains a major hurdle in nanomedicine. The endosomal escape of pH-responsive, self-assembled, dual component particles based on poly[2-(diethylamino)ethyl methacrylate)(PDEAEMA) and poly(ethylene glycol)-b-poly[2-(diethylamino)ethyl methacrylate) (PEG-b-PDEAEMA) has been recently reported. Herein, we report that polymer molecular weight (M
Fabrication of asymmetric Janus'' particles via plasma polymerization
Publisher: Royal Society of Chemistry (RSC)
Date: 2010
DOI: 10.1039/C0CC00474J
Abstract: A versatile approach has been developed using plasma polymerization to fabricate functional Janus particles. A brominated plasma polymer is toposelectively deposited on a monolayer of silica microparticles, endowing the particles with a chemically reactive polymeric and silica hemisphere.
Fundamental studies of hybrid poly(2-(diisopropylamino)ethyl methacrylate)/poly(N-vinylpyrrolidone) films and capsules
Publisher: American Chemical Society (ACS)
Date: 27-06-2014
DOI: 10.1021/BM500640T
Abstract: Hybrid and multicompartment carriers are of significant interest for the development of next-generation therapeutic drug carriers. Herein, fundamental investigations on layer-by-layer (LbL) capsules consisting of two different polymers are presented. The hybrid systems were designed to have pH-responsive, charge-shifting poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) inner layers and low-fouling poly(N-vinylpyrrolidone) (PVPON) outer layers. Planar hybrid films with different layer ratios were studied by quartz crystal microgravimetry (QCM) and atomic force microscopy (AFM). The information obtained was translated to particulate templates to prepare hybrid capsules, which were stabilized by click chemistry. The charge-shifting behavior of PDPA improved the cargo encapsulation and initial retention of a model CpG cargo, while outer layers of PVPON improved biofouling properties compared to single-component PDPA capsules. The results demonstrate the need to understand and design multifunctional systems that can successfully embody different functionalities in a single, stable construct for the fabrication of next-generation drug and gene delivery carriers aimed at overcoming the challenges encountered in biological systems.
Assembly of ultrathin polymer multilayer films by click chemistry
Publisher: American Chemical Society (ACS)
Date: 28-06-2006
DOI: 10.1021/JA063043+
Abstract: Layer-by-layer (LbL) assembly is a versatile and robust technique for fabricating tailored thin films of erse composition. Herein we report a new method of covalent coupling, click chemistry, to facilitate the LbL assembly of thin films. Linear film growth was observed using both UV-vis and FTIR spectroscopy, and film thicknesses were determined by ellipsometry and atomic force microscopy. The assembled films are shown to be stable in a wide pH range. This technique offers the potential to enable the synthesis of new types of stable and responsive LbL films from a variety of polymers.
Targeting cancer cells: Controlling the binding and internalization of antibody-functionalized capsules
Publisher: American Chemical Society (ACS)
Date: 07-08-2012
DOI: 10.1021/NN3010476
Abstract: The development of nanoengineered particles, such as polymersomes, liposomes, and polymer capsules, has the potential to offer significant advances in vaccine and cancer therapy. However, the effectiveness of these carriers has the potential to be greatly improved if they can be specifically delivered to target cells. We describe a general method for functionalizing nanoengineered polymer capsules with antibodies using click chemistry and investigate their interaction with cancer cells in vitro. The binding efficiency to cells was found to be dependent on both the capsule-to-cell ratio and the density of antibody on the capsule surface. In mixed cell populations, more than 90% of target cells bound capsules when the capsule-to-target cell ratio was 1:1. Strikingly, greater than 50% of target cells exhibited capsules on the cell surface even when the target cells were present as less than 0.1% of the total cell population. Imaging flow cytometry was used to quantify the internalization of the capsules, and the target cells were found to internalize capsules efficiently. However, the role of the antibody in this process was determined to enhance accumulation of capsules on the cell surface rather than promote endocytosis. This represents a significant finding, as this is the first study into the role antibodies play in internalization of such capsules. It also opens up the possibility of targeting these capsules to cancer cells using targeting molecules that do not trigger an endocytic pathway. We envisage that this approach will be generally applicable to the specific targeting of a variety of nanoengineered materials to cells.
Layer-by-Layer Assembled Capsules for Biomedical Applications
Publisher: Elsevier
Date: 2011
Rationale Design of pH-Responsive Core–Shell Nanoparticles: Polyoxometalate-Mediated Structural Reorganization
Publisher: American Chemical Society (ACS)
Date: 02-11-2020
One-Step Assembly of Coordination Complexes for Versatile Film and Particle Engineering
Publisher: American Association for the Advancement of Science (AAAS)
Date: 12-07-2013
Abstract: Thin adherent films formed from ferric ions and a natural polyphenol, tannic acid, can coat a wide variety of surfaces. [Also see Perspective by Bentley and Payne ]
Lewis Base Catalyzed Synthesis of Sulfur Heterocycles via the C1‐Pyridinium Enolate
Publisher: Wiley
Date: 11-07-2022
Abstract: While the addition of C1‐Lewis base enolates to carbonyls and related structures are well established, the related addition to thiocarbonyls compounds are unknown. Herein, we report a reaction cascade in which a C1‐pyridinium enolate undergos addition to dithioesters, trithiocarbonates and xanthates. The reaction provides access to a range of dihydrothiophenes and dihydrothiopyrans (28‐ex les). Mechanistic investigations, including isolation of intermediates, electronic correlation, and kinetic isotope effect studies support the viability of an activated acid intermediate giving rise to the C1‐pyridinium enolate which undergoes turnover limiting cyclization. Subsequent formation of a β‐thiolactone regenerates the catalyst with loss of carbon oxysulfide providing the observed products.
Design of Degradable Click Delivery Systems
Publisher: Wiley
Date: 06-05-2013
Abstract: Click chemistry has had a significant impact in the field of materials science over the last 10 years, as it has enabled the design of new hybrid building blocks, leading to multifunctional and responsive materials. One key application for such materials is in the biomedical field, such as gene or drug delivery. However, to meet the functional requirements of such applications, tailored degradability of these materials under biological conditions is critical. There has been an increasing interest in combining click chemistry techniques with a range of degradable or responsive building blocks as well as investigating new or milder chemistries to design click delivery systems that are capable of physiologically relevant degradation. This Feature Article will cover some of the different approaches to synthesize degradable click delivery systems and their investigation for therapeutic release.
Polyoxometalates as chemically and structurally versatile components in self-assembled materials
Publisher: Royal Society of Chemistry (RSC)
Date: 2022
DOI: 10.1039/D1SC05879G
Abstract: Polyoxometalates are anionic molecular metal oxides with ersity in composition, structure, nuclearity and charge. Their adaptable chemistry leads to potential for self-assembly with other building blocks into a variety of hybrid structures.
Triggering release of encapsulated cargo
Publisher: Wiley
Date: 26-03-2010
PH-Responsive Transferrin-pHlexi particles capable of targeting cells in vitro
Publisher: American Chemical Society (ACS)
Date: 09-03-2017
Engineered Layer-by-Layer Assembled Capsules for Biomedical Applications
Publisher: Wiley
Date: 09-05-2012
Research Trends in Photochromism: Control of Photochromism in Rigid Polymer Matrices and other Advances
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/CH05049
Abstract: Photochromism is receiving increasing attention because of its current application in high value-added ophthalmic lenses and potential applications in data storage and molecular switching. The performance of photochromic dyes, such as spirooxazines, chromenes, and diarylethenes, in polymers is important because the above applications require the dyes to be in a host polymer. The dyes can be broadly ided into P (photo) and T (thermal) types depending on the availability of a thermal decolouration route. Current research themes for the two types are presented with an emphasis on a new method of manipulating switching speeds in polymer matrices.
Tuning the properties of pH responsive nanoparticles to control cellular interactions in vitro and ex vivo
Publisher: Royal Society of Chemistry (RSC)
Date: 2016
DOI: 10.1039/C6PY01332E
Abstract: Engineering the properties of nanoparticles to limit non-specific cellular interactions is critical for developing effective drug delivery systems. Differences between interactions with cultured cells and human blood highlights the need for appropriate assays.
Rapid Photochromic Switching in a Rigid Polymer Matrix Using Living Radical Polymerization
Publisher: American Chemical Society (ACS)
Date: 21-01-2006
DOI: 10.1021/MA052002F
Factors Influencing Photochromism of Spiro-Compounds Within Polymeric Matrices
Publisher: Informa UK Limited
Date: 31-12-2003
DOI: 10.1081/MC-120025978
Polymersome-loaded capsules for controlled release of DNA
Publisher: Wiley
Date: 04-07-2011
Abstract: The formation of a novel drug-delivery carrier for the controlled release of plasmid DNA that comprises layer-by-layer polymer capsules subcompartmentalized with pH-sensitive nanometer-sized polymersomes is reported. The hiphilic diblock copolymer poly(oligoethylene glycol methacrylate)-block-poly(2-(diisopropylamino)ethyl methacrylate) forms polymersomes at physiological pH, but transitions to unimeric polymer chains upon acidification to cellular endocytic pH. These polymersomes can thus release an encapsulated payload in response to a change in pH from physiological to endocytic conditions. Multicomponent layer-by-layer capsules are formed by exploiting the ability of tannic acid to act as an efficient hydrogen-bond donor for both the polymersomes and poly(N-vinyl pyrrolidone) at physiological pH. These capsules show release of a plasmid DNA payload encapsulated within the polymersome subcompartments in response to changes in pH between physiological and endocytic conditions.
Click-engineered, bioresponsive, drug-loaded PEG spheres
Publisher: Wiley
Date: 20-11-2009
Abstract: A click-chemistry approach to synthesize bioresponsive poly(ethylene glycol acrylate) particles is described. The particles are loaded with a model anticancer drug (doxorubicin, DOX), and undergo simultaneous particle deconstruction and DOX release upon specific activation by the simulated environment of the cellular cytoplasm.
Endocytic pH-triggered degradation of nanoengineered multilayer capsules
Publisher: Wiley
Date: 27-12-2014
Abstract: The synthesis of cross-linker free layer-by-layer (LbL) capsules that solely utilize cellular pH variations as a trigger to specifically deconstruct and subsequently release cargo in cells is reported. These capsules demonstrate retention of water-soluble therapeutic molecules as small as 500 Da at extracellular pH. Triggered capsule degradation and release of cargo is observed within 30 min of cell uptake.
Bypassing Multidrug Resistance in Cancer Cells with Biodegradable Polymer Capsules
Publisher: Wiley
Date: 25-10-2010
Self-healing organic coatings – Fundamental chemistry to commercial application
Publisher: Elsevier BV
Date: 10-2023
Quantifying Nanoparticle Internalization Using a High Throughput Internalization Assay
Publisher: Springer Science and Business Media LLC
Date: 05-07-2016
DOI: 10.1007/S11095-016-1984-3
Abstract: The internalization of nanoparticles into cells is critical for effective nanoparticle mediated drug delivery. To investigate the kinetics and mechanism of internalization of nanoparticles into cells we have developed a DNA molecular sensor, termed the Specific Hybridization Internalization Probe - SHIP. Self-assembling polymeric 'pHlexi' nanoparticles were functionalized with a Fluorescent Internalization Probe (FIP) and the interactions with two different cell lines (3T3 and CEM cells) were studied. The kinetics of internalization were quantified and chemical inhibitors that inhibited energy dependent endocytosis (sodium azide), dynamin dependent endocytosis (Dyngo-4a) and macropinocytosis (5-(N-ethyl-N-isopropyl) amiloride (EIPA)) were used to study the mechanism of internalization. Nanoparticle internalization kinetics were significantly faster in 3T3 cells than CEM cells. We have shown that ~90% of the nanoparticles associated with 3T3 cells were internalized, compared to only 20% of the nanoparticles associated with CEM cells. Nanoparticle uptake was via a dynamin-dependent pathway, and the nanoparticles were trafficked to lysosomal compartments once internalized. SHIP is able to distinguish between nanoparticles that are associated on the outer cell membrane from nanoparticles that are internalized. This study demonstrates the assay can be used to probe the kinetics of nanoparticle internalization and the mechanisms by which the nanoparticles are taken up by cells. This information is fundamental for engineering more effective nanoparticle delivery systems. The SHIP assay is a simple and a high-throughput technique that could have wide application in therapeutic delivery research.
Next generation, sequentially assembled ultrathin films: Beyond electrostatics
Publisher: Royal Society of Chemistry (RSC)
Date: 2007
DOI: 10.1039/B610778H
Abstract: Over the last 15 years, the layer-by-layer (LbL) assembly technology has proven to be a versatile method for surface modification. This approach is likely to find widespread application because of its simplicity and versatility however, the conventional use of highly charged materials with limited responsive behaviour presents some key limitations. In this tutorial review, the formation of multilayer thin films prepared through non-electrostatic interactions is reviewed. We discuss the assembly of films via a number of different methodologies, with particular emphasis on those that provide enhanced orientational control, stimuli-responsive behaviour, and improved film stability.
Related Organisations
Related Funding Activities
Discovery Projects - Grant ID: DP0986222
Start Date: 2009
End Date: 06-2012
Amount: $300,000.00
Funder: Australian Research Council
View Funded ActivityARC Future Fellowships - Grant ID: FT120100564
Start Date: 03-2013
End Date: 06-2017
Amount: $709,778.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP180100844
Start Date: 2018
End Date: 12-2020
Amount: $438,161.00
Funder: Australian Research Council
View Funded ActivityDiscovery Projects - Grant ID: DP210103174
Start Date: 12-2021
End Date: 12-2023
Amount: $420,000.00
Funder: Australian Research Council
View Funded ActivityIndustrial Transformation Training Centres - Grant ID: IC170100020
Start Date: 07-2018
End Date: 12-2024
Amount: $3,279,502.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE120100131
Start Date: 02-2012
End Date: 02-2013
Amount: $150,000.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE210100100
Start Date: 04-2021
End Date: 12-2023
Amount: $975,934.00
Funder: Australian Research Council
View Funded ActivityLinkage Infrastructure, Equipment And Facilities - Grant ID: LE0989341
Start Date: 10-2009
End Date: 12-2010
Amount: $690,000.00
Funder: Australian Research Council
View Funded Activity