Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Dual Stimuli - Dual Response Nanoassemblies Prepared from a Simple Homopolymer.

ABSTRACT: A dual stimuli responsive nanogel-polyelectrolyte complex based on electrostatic coating has been developed. The nanoassembly is designed to elicit two disparate responses (viz. surface property change and guest encapsulation stability) from two different stimuli (viz. pH and redox variations). The components of the nanogel and the polyelectrolyte have been conveniently achieved from a simple homopolymer, poly(pentafluorophenylacrylate).

SUBMITTER: Zhuang J

PROVIDER: S-EPMC3917511 | biostudies-literature | 2014 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Dual Stimuli - Dual Response Nanoassemblies Prepared from a Simple Homopolymer.

Zhuang Jiaming J Chacko Reuben R Amado Torres Diego F DF Wang Hui H Thayumanavan S S

ACS macro letters 20140101 1

A dual stimuli responsive nanogel-polyelectrolyte complex based on electrostatic coating has been developed. The nanoassembly is designed to elicit two disparate responses (<i>viz.</i> surface property change and guest encapsulation stability) from two different stimuli (<i>viz.</i> pH and redox variations). The components of the nanogel and the polyelectrolyte have been conveniently achieved from a simple homopolymer, poly(pentafluorophenylacrylate). ...[more]

PMID: 24516780

Similar Datasets

Dual-stimuli-responsive microparticles.

Project description:The need for smart materials in the area of biotechnology has fueled the development of numerous stimuli-responsive polymers. Many of these polymers are responsive to pH, light, temperature, or oxidative stress, and yet very few are responsive toward multiple stimuli. Here we report on the synthesis of a novel dual-stimuli-responsive poly(ethylene glycol)-based polymer capable of changing its hydrophilic properties upon treatment with UV light (exogenous stimulus) and markers of oxidative stress (endogenous stimulus). From this polymer, smart microparticles and fibers were fabricated and their responses to either stimulus separately and in conjunction were examined. Comparison of the degradation kinetics demonstrated that the polymer became water-soluble only after both oxidation and irradiation with UV light, which resulted in selective degradation of the corresponding particles. Furthermore, in vitro experiments demonstrated successful uptake of these particles by Raw 264.7 cells. Such dual-stimuli-responsive particles could have potential applications in drug delivery, imaging, and tissue engineering.

| S-EPMC5665401 | biostudies-literature

Simple microfluidic device for studying chemotaxis in response to dual gradients.

Project description:Chemotaxis is a fundamental biological process where complex chemotactic gradients are integrated and prioritized to guide cell migration toward specific locations. To understand the mechanisms of gradient dependent cell migration, it is important to develop in vitro models that recapitulate key attributes of the chemotactic cues present in vivo. Current in vitro tools for studying cell migration are not amenable to easily study the response of neutrophils to dual gradients. Many of these systems require external pumps and complex setups to establish and maintain the gradients. Here we report a simple yet innovative microfluidic device for studying cell migration in the presence of dual chemotactic gradients through a 3-dimensional substrate. The device is tested and validated by studying the migration of the neutrophil-like cell line PLB-985 to gradients of fMLP. Furthermore, the device is expanded and used with heparinised whole blood, whereupon neutrophils were observed to migrate from whole blood towards gradients of fMLP eliminating the need for any neutrophil purification or capture steps.

| S-EPMC4768479 | biostudies-literature

Dual Stimuli-Triggered Nanogels in Response to Temperature and pH Changes for Controlled Drug Release.

Project description:Poly-N-isopropyl acrylamide (PNIPAM) nanogels have been modified with different acrylic acid (AAc) contents for the efficient control of lower critical solution temperature (LCST). In this study, PNIPAM-co-AAc nanogels nanogels showed two volume phase transitions in comparison with PNIPAM. The transition temperature of PNIPAM nanogels was increased with AAc contents. The controlled drug release performance of PNIPAM-co-AAc nanogels loaded with β-lapachone was attributed to the AAc content ratio and was efficiently triggered in response to temperature and pH. Moreover, a colorimetric cell proliferation assay and direct fluorescence-based live/dead staining were used to confirm the concurrence on drug release profiles. Finally, PNIPAM-co-AAc20 showed a relatively low level of drug release in the range of acidic to neutral pH at body temperature, while maximizing drug release at basic pH. Therefore, we demonstrated that the PNIPAM-based nanogel with the temperature- and pH-responsive features could be a promising nanocarrier for potential intestine-specific drug delivery.

| S-EPMC6399374 | biostudies-literature

Size and charge dual-transformable mesoporous nanoassemblies for enhanced drug delivery and tumor penetration.

Project description:A series of biological barriers in a nanoparticle-formulated drug delivery process inevitably result in the current low delivery efficiency, limited tumor penetration and insufficient cellular internalization of drugs. These multiple biological barriers are intimately related to the physicochemical properties of nanoparticles, especially the contradictory demand on size and surface charge for long blood circulation (larger and negative) and deep tumor penetration (smaller) as well as efficient cellular internalization (positive). Herein, we report tumor microenvironment triggered size and charge dual-transformable nanoassemblies. The nanoassembly is realized by immobilizing positive up/downconverting luminescent nanoparticles (U/DCNPs) onto large mesoporous silica nanoparticles (MSNs) via acid-labile bonds to form core@satellite structured MSN@U/DCNPs nanoassemblies, and subsequent capping of charge reversible polymers. At physiological pH, the integrated nanoassemblies with a larger size (∼180 nm) and negative charge can effectively achieve a prolonged blood circulation and high tumor accumulation. While under an acidic tumor microenvironment, the charge reversal of outer polymers and cleavage of linkers between MSNs and U/DCNPs can induce disintegration of the nanoassemblies into isolated MSNs and smaller U/DCNPs, both with a positively charged surface, which thereby potentiate the tumor penetration and cell uptake of dissociated nanoparticles. Combined with the independent near-infrared (NIR)-to-visible and NIR-to-NIR luminescence of U/DCNPs and high surface area of MSNs, the nanoassemblies can implement NIR bioimaging guided chemo- and photodynamic combined therapy with remarkable antitumor efficiency because of the high accumulation and deep tumor penetration induced by the dual transformability of the nanoassemblies.

| S-EPMC8157500 | biostudies-literature

Hybrid chalcogen bonds in prodrug nanoassemblies provides dual redox-responsivity in the tumor microenvironment.

Project description:Sulfur bonds, especially trisulfide bond, have been found to ameliorate the self-assembly stability of homodimeric prodrug nanoassemblies and could trigger the sensitive reduction-responsive release of active drugs. However, the antitumor efficacy of homodimeric prodrug nanoassemblies with single reduction-responsivity may be restricted due to the heterogeneous tumor redox microenvironment. Herein, we replace the middle sulfur atom of trisulfide bond with an oxidizing tellurium atom or selenium atom to construct redox dual-responsive sulfur-tellurium-sulfur and sulfur-selenium-sulfur hybrid chalcogen bonds. The hybrid chalcogen bonds, especially the sulfur-tellurium-sulfur bond, exhibit ultrahigh dual-responsivity to both oxidation and reduction conditions, which could effectively address the heterogeneous tumor microenvironment. Moreover, the hybrid sulfur-tellurium-sulfur bond promotes the self-assembly of homodimeric prodrugs by providing strong intermolecular forces and sufficient steric hindrance. The above advantages of sulfur-tellurium-sulfur bridged homodimeric prodrug nanoassemblies result in the improved antitumor efficacy of docetaxel with satisfactory safety. The exploration of hybrid chalcogen bonds in drug delivery deepened insight into the development of prodrug-based chemotherapy to address tumor redox heterogeneity, thus enriching the design theory of prodrug-based nanomedicines.

| S-EPMC9700694 | biostudies-literature

Prepared stimuli enhance aversive learning without weakening the impact of verbal instructions.

Project description:Fear-relevant stimuli such as snakes and spiders are thought to capture attention due to evolutionary significance. Classical conditioning experiments indicate that these stimuli accelerate learning, while instructed extinction experiments suggest they may be less responsive to instructions. We manipulated stimulus type during instructed aversive reversal learning and used quantitative modeling to simultaneously test both hypotheses. Skin conductance reversed immediately upon instruction in both groups. However, fear-relevant stimuli enhanced dynamic learning, as measured by higher learning rates in participants conditioned with images of snakes and spiders. Results are consistent with findings that dissociable neural pathways underlie feedback-driven and instructed aversive learning.

| S-EPMC5772389 | biostudies-literature

Multi-Stimuli-Responsive Amphiphilic Assemblies through Simple Postpolymerization Modifications.

Project description:A strategy to construct different stimuli responsive polymers from post polymerization modifications of a single polymer scaffold via thiol-disulfide exchange has been developed. Here, we report on a random copolymer that enables the design and syntheses of a series of dual or multi-stimuli responsive nanoassemblies using a simple post-polymerization modification step. The reactive functional group involves a side chain monopyridyl disulfide unit, which rapidly and quantitatively reacts with various thiols under mild conditions. Independent and concurrent incorporation of physical, chemical or biologically responsive properties have been demonstrated. We envision that this strategy may open up opportunities to simplify the synthesis of multi-functional polymers with broad implications in a variety of biological applications.

| S-EPMC5774634 | biostudies-literature

Dual-Emissive Waterborne Polyurethanes Prepared from Naphthalimide Derivative.

Project description:Fluorescent and room-temperature phosphorescent (RTP) materials are widely used in bioimaging, chemical sensing, optoelectronics and encryption. Here, a series of single-component dual-emissive waterborne polyurethanes (WPUs) with both fluorescence and room-temperature phosphorescence were synthesized. Dye without halogen atom incorporated into WPUs can only exhibit fluorescence due to poor spin-orbit coupling. When bromine atom is introduced into dye, we found that WPUs can emit both fluorescence and room-temperature phosphorescence with lifetimes up to milliseconds because of enhanced spin-orbit coupling. Moreover, with an increase in dye concentrations in WPUs, excimers are formed due to the aggregation effect, and may promote communication between singlet and triplet states. At different dye concentrations, structural, thermal, and luminescent properties serve as the main focus.

| S-EPMC6418983 | biostudies-literature

Dual Stimuli-Responsive P(NIPAAm-co-SPA) Copolymers: Synthesis and Response in Solution and in Films.

Project description:We present the synthesis and solution properties of dual stimuli-responsive poly(N-isopropylacrylamide-co-spiropyran acrylate) (P(NIPAAm-co-SPA)) copolymers of varying composition prepared via nitroxide-mediated copolymerization. The resulting copolymers feature molar masses from 40,000 to 100,000 g/mol according to static light scattering and an SPA content of up to 5.3%. The latter was determined by ¹H NMR spectroscopy and UV⁻Vis spectroscopy. These materials exhibit reversible response upon irradiation in polymeric films for a minimum of three cycles; their response in solution to both light and temperature was also investigated in an aqueous TRIS buffer (pH 8). Irradiation was carried out using LED setups with wavelengths of 365 and 590 nm. In aqueous solution, a custom-made setup using a fiber-coupled 200 W Hg(Xe) lamp with 340 and 540 nm filters was used and additional heating of the copolymer solutions during irradiation allowed to study influence of the presence of either the spiropyran or merocyanine form on the cloud point temperature. Hereby, it was found that increasing the SPA content leads to a more pronounced difference between both states and decreasing cloud points in general.

| S-EPMC6403943 | biostudies-literature

Thermoresponsive Poly(ß-hydroxyl amine)s: Synthesis of a New Stimuli Responsive Amphiphilic Homopolymer Family through Amine-Epoxy 'Click' Polymerization.

Project description:A new synthesis of amphiphilic homopolymers is described. In this synthesis, commercially available and inexpensive primary amines and di-epoxide molecules are utilized as AA- and BB-types of monomers in an amine-epoxy 'click' polymerization process. This process can be carried out in water and at room temperature. It does not require a catalyst or inert conditions and forms no byproducts. Therefore, the polymer synthesis can be carried out in open-air and bench-top conditions and a post-synthesis purification step is not required. The modularity of the synthesis, on the other hand, allows for facile structural modulation and tuning of the thermally triggered aggregation process in the temperature range of 7 to 91 °C. Finally, the underlying principles can be translated from linear architectures to polymer networks (hydrogels).

| S-EPMC6961043 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data