Topics

Accelerated Local Dynamics in Matrix-Free Polymer Grafted Nanoparticles.

08:00 EDT 11th October 2019 | BioPortfolio

Summary of "Accelerated Local Dynamics in Matrix-Free Polymer Grafted Nanoparticles."

The tracer diffusion coefficient of six different permanent gases in polymer-grafted nanoparticle (GNP) membranes, i.e., neat GNP constructs with no solvent, show a maximum as a function of the grafted chain length at fixed grafting density. This trend is reproduced for two different NP sizes and three different polymer chemistries. We postulate that nonmonotonic changes in local, segmental friction as a function of graft chain length (at fixed grafting density) must underpin these effects, and use quasielastic neutron scattering to probe the self-motions of polymer chains at the relevant segmental scale (i.e., sampling local friction or viscosity). These data, when interpreted with a jump diffusion model, show that, in addition to the speeding-up in local chain dynamics, the elementary distance over which segments hop is strongly dependent on graft chain length. We therefore conclude that transport modifications in these GNP layers, which are underpinned by a structural transition from a concentrated brush to semidilute polymer brush, are a consequence of both spatial and temporal changes, both of which are likely driven by the lower polymer densities of the GNPs relative to the neat polymer.

Affiliation

Journal Details

This article was published in the following journal.

Name: Physical review letters
ISSN: 1079-7114
Pages: 158003

Links

DeepDyve research library

PubMed Articles [19683 Associated PubMed Articles listed on BioPortfolio]

Characterizing Polymer-Grafted Nanoparticles: From Basic Defining Parameters to Behavior in Solvents and Self-Assembled Structures.

Polymer-grafted nanoparticles, often called hairy nanoparticles (HNPs), are an intriguing class of nanostructured hybrid materials with great potential in a variety of applications, including advanced...

Time-Resolved Analysis of the Structural Dynamics of Assembling Gold Nanoparticles.

The hydrophobic collapse is a structural transition of grafted polymer chains in a poor solvent. Although such a transition seems an intrinsic event during clustering of polymer-stabilized nanoparticl...

Structural Properties and Magnetic Ordering in 2D Polymer Nanocomposites: Existence of Long Magnetic Dipolar Chains in Zero Field.

The existence of magnetic dipolar nanoparticle chains at zero field has been predicted theoretically for decades, but these structures are rarely observed experimentally. A prerequisite is a permanen...

Synergy between polymer crystallinity and nanoparticles size for payloads release.

Drug delivery from polymer nanocarriers is usually achieved by designing polymers so that they release drugs by cleavage of labile bonds, or by preparing nanoparticles that swell or collapse in respon...

Controlling Size and Fluorescence of Dye-Loaded Polymer Nanoparticles through Polymer Design.

Nanoprecipitation is a straightforward yet powerful technique to synthesize polymer nanoparticles loaded with various biologically active compounds or contrast agents. Particle formation in this appro...

Clinical Trials [6401 Associated Clinical Trials listed on BioPortfolio]

EASYX-1 : A Multicenter Study on Safety and Efficacy of Easyx Liquid Embolization Agent Used in Five Separate Indications

The EASYX™ Liquid Embolic is a new injectable, precipitating polymeric agent for the obliteration of vascular spaces through direct puncture or catheter access performed under X-ray guid...

Polymer Free Stent in Acute Coronary Syndrome

To evaluate the short term out comes of the polymer free stents in patients presented with non ST elevation acute coronary syndrome (which include ST depression myocardial infarction and u...

Medtronic Polymer-Free Drug-Eluting Coronary Stent System

The purpose of this trial is to evaluate the clinical safety and efficacy of the Polymer-Free Drug-Eluting coronary stent system for the treatment of de novo lesions in native coronary art...

Randomized Trial of ARCON in Larynx Cancer

TITLE: A multicentre, randomised, phase III clinical trial comparing accelerated radiotherapy with accelerated radiotherapy plus carbogen and nicotinamide (ARCON) in clinical stage T2-4 ...

Topical Silver Nanoparticles for Microbial Activity

Silver nanoparticles are one of most nanoparticles use nowadays in the research area because it has specific physical and chemical properties, in medical fields silver nanoparticles can in...

Medical and Biotech [MESH] Definitions

Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.

Strongly cationic polymer that binds to certain proteins; used as a marker in immunology, to precipitate and purify enzymes and lipids. Synonyms: aziridine polymer; Epamine; Epomine; ethylenimine polymer; Montrek; PEI; Polymin(e).

A proteoglycan family (SLRPs) that is defined by a central domain which consists of a variable number of repeats of the motif LXXLxLXXNxL, where L may be LEUCINE; ISOLEUCINE; VALINE; or other hydrophobic amino acids. The N-terminal contains four conserved CYSTEINE residues and may be modified depending on function. SLRPs provide structural support to the EXTRACELLULAR MATRIX and are critical for regulating its assembly and dynamics at CELL-MATRIX JUNCTIONS.

Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.

A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.

Quick Search


DeepDyve research library

Searches Linking to this Article