PEGDA hydrogel structure from semi-dilute concentrations: insights from experiments and molecular simulations.

The efficacy of hydrogel materials used in biomedical applications is dependent on polymer network topology and the structure of water-laden pore space. Hydrogel microstructure can be tuned by adjusting synthesis parameters such as macromer molar mass and concentration. Moreover, hydrogels beyond dilute conditions are needed to produce mechanically robust and dense networks for tissue engineering and/or drug delivery systems.

Molecular Modeling of Complex Cross-Linked Networks of PEGDA Nanogels.

Poly(ethylene glycol) (PEG)-based nanogels are attractive for biomedical applications due to their biocompatibility, versatile end group chemistry, and ability to sterically shield encapsulated drug molecules. The characteristics of a hydrogel network govern the encapsulation and efficient delivery of drug molecules for a target application. A molecular-level description of network topology can complement experimental investigations to understand its effects on the structural properties of these nanogels.

Ionic-Functionalized Polymers of Intrinsic Microporosity for Gas Separation Applications.

Ionic-functionalized microporous materials are attractive for energy-efficient gas adsorption and separation processes and have shown promising results in gas mixtures at pressure ranges and compositions that are relevant for industrial applications. In this work, we studied the influence of different counterions (Li, Na, K, Rb, and Mg) on the porosity, carbon dioxide (CO) gas adsorption, and selectivity in ionic-functionalized PIM-1 (IonomIMs), a polymer belonging to the class of linear and amorphous microporous polymers known as polymers of intrinsic microporosity (PIMs). It was found that an increase in the concentration of ionic groups led to a decrease in the free volume, resulting in a less porous polymer framework, and Mg-functionalized IonomIMs exhibited a relatively larger porosity compared to other IonomIMs.

Effect of introducing a short amyloidogenic sequence from the Aβ peptide at the N-terminus of 18-residue amphipathic helical peptides.

Fibril formation is the hallmark of pathogenesis in Alzheimer's disease and other amyloid disorders caused by conformational alterations leading to the aggregation of soluble monomers. Aβ40 self-associates to form amyloid fibrils. Its central seven-residue segment KLVFFAE (Aβ16-22), which is thought to be crucial for fibril formation of the full-length peptide, forms fibrils even in isolation.