Impact of Hydroxypropyl Methylcellulose Acetate Succinate Critical Aggregation Concentration on Celecoxib Supersaturation.

Polymers play an important role in amorphous solid dispersions (ASDs), enhancing stability in the solid state and maintaining supersaturation in aqueous solutions of intrinsically low-water-soluble drug candidates. Hydroxypropyl methylcellulose acetate succinate (HPMCAS) is widely used in ASDs due to its hydrophobic/hydrophilic balance and ionizability of the substituent functionalities. While colloid formation of HPMCAS in solution due to this hydrophobic/hydrophilic balance has been studied, the impact of the polymer conformation (random coil vs aggregated) on drug supersaturation of ASDs is not well understood.

Effects of Stereochemistry and Hydrogen Bonding on Glycopolymer-Amyloid-β Interactions.

Saccharide stereochemistry plays an important role in carbohydrate functions such as biological recognition processes and protein binding. Synthetic glycopolymers with pendant saccharides of controlled stereochemistry provide an attractive approach for the design of polysaccharide-inspired biomaterials. Acrylamide-based polymers containing either β,d-glucose or β,d-galactose pendant groups, designed to mimic GM1 ganglioside saccharides, and their small-molecule analogues were used to evaluate the effect of stereochemistry on glycopolymer solution aggregation processes alone and in the presence of Aβ42 peptide using dynamic light scattering, gel permeation chromatography-multiangle laser light scattering, and fluorescence assays.

Aqueous RAFT Synthesis of Low Molecular Weight Anionic Polymers for Determination of Structure/Binding Interactions with Gliadin.

Gliadin, a component of gluten and a known epitope, is implicated in celiac disease (CeD) and results in an inflammatory response in CeD patients when consumed. Acrylamide-based polyelectrolytes are employed as models to determine the effect of molecular weight and pendent group on non-covalent interaction modes with gliadin in vitro. Poly(sodium 2-acrylamido-2-methylpropane sulfonate) and poly(sodium 3-methylpropyl-3-butanoate) are synthesized via aqueous reversible addition fragmentation chain transfer (aRAFT) polymerization and characterized by gel permeation chromatography-multiangle laser light scattering.

Enhanced Surface Properties of Branched Poly(ether sulfone) from Semifluorinated Polyhedral Oligomeric Silsequioxanes.

Hybrid systems in which poly(ether sulfone) (PESU) chains are grafted to semifluorinated polyhedral oligomeric silsesquioxane (POSS) cores are expected to integrate the advantages of both fluoropolymers and POSS into the polymer system to yield excellent surface properties. For that purpose, we synthesized a novel octa-functional perfluorocyclopentenyl-POSS (PFCP-POSS), which was used as a "core" grafting point. Commercial PESU was successfully grafted to PFCP-POSS via the nucleophilic addition-elimination reaction between the phenolic chain ends and reactive PFCP moieties to yield a hybrid branched polymer possessing a semifluorinated POSS core.