Partial Destabilization of Amyloid-β Protofibril by Methionine Photo-Oxidation: A Molecular Dynamic Simulation Study.

Selective photosensitized oxidation of amyloid protein aggregates is being investigated as a possible therapeutic strategy for treating Alzheimer's disease (AD). Photo-oxidation has been shown to degrade amyloid-β (Aβ) aggregates and ameliorate aggregate toxicity in vitro and reduce aggregate levels in the brains of AD animal models. To shed light on the mechanism by which photo-oxidation induces fibril destabilization, we carried out an all-atom molecular dynamics (MD) simulation to examine the effect of methionine (Met35) oxidation on the conformation and stability of a β-sheet-rich Aβ protofibril.

Understanding the Photochemical Properties of Polythiophene Polyelectrolyte Soft Aggregates with Sodium Dodecyl Sulfate for Antimicrobial Activity.

The threat of antibiotic-resistant bacteria is an ever-increasing problem in public health. In this report, we examine the photochemical properties with a proof-of-principle biocidal assay for a novel series of regio-regular imidazolium derivative poly-(3-hexylthiophene)/sodium dodecyl sulfate (P3HT-Im/SDS) materials from ultrafast sub-ps dynamics to μs generation of reactive oxygen species (ROS) and 30 min biocidal reactivity with (). This broad series encompassing pure P3HT-Im to cationic, neutral, and anionic P3HT-Im/SDS materials are all interrogated by a variety of techniques to characterize the physical material structure, electronic structure, and antimicrobial activity.

Quantitative Determination of Dark and Light-Activated Antimicrobial Activity of Poly(Phenylene Ethynylene), Polythiophene, and Oligo(Phenylene Ethynylene) Electrolytes.

Much recent effort has been directed toward the development of novel antimicrobial materials able to defeat new and antibiotic resistant pathogens. In this report, we study the efficacy of cationic poly(phenylene ethynylene), polythiophene, and oligo(phenylene ethynylene) electrolytes against laboratory strains of and . The focus of the study is to quantitatively evaluate the speed and extent of dark and light-activated antimicrobial activity.

Doxorubicin delivery via magnetic nanomicelles comprising from reduction-responsive poly(ethylene glycol)‑b‑poly(ε‑caprolactone) (PEG-SS-PCL) and loaded with superparamagnetic iron oxide (SPIO) nanoparticles: Preparation, characterization and simulation.

Reduction-responsive biodegradable micelles were prepared by linking of poly(ethylene glycol) and poly(ε‑caprolactone) with disulfide bond (PEG-SS-PCL) for co-delivery of superparamagnetic iron oxide (SPIO) nanoparticles (NPs) and an anticancer agent, doxorubicin (DOX). This amphiphilic diblock copolymer shows redox-responsive properties, which is arising from disulfide bonds throughout the main chain. The ability of these copolymers for self-assembly with oleic acid modified SPIONs can help to organize nanomicelles in aqueous solution.

Dynamic stability of nano-fibers self-assembled from short amphiphilic AD peptides.

Self-assembly of AD amphiphilic peptides in explicit water is studied by using coarse-grained molecular dynamics simulations. It is observed that the self-assembly of randomly distributed AD peptides leads to the formation of a network of nano-fibers. Two other simulations with cylindrical nano-fibers as the initial configuration show the dynamic stability of the self-assembled nano-fibers.