Poly(glycerol sebacate) (PGS) is an elastomeric polymer which is attracting increasing interest for biomedical applications, including cartilage regeneration. However, its limited mechanical properties and possible negative effects of its degradation byproducts restrict PGS for in vivo application. In this study, a novel PGS-bioactive glass fiber (F18)-reinforced composite was developed and cha...

Effect of alkyl group substituents on the thermal and enzymatic degradation of poly (n-alkyl acrylates) J. P. Mahalik and Giridhar Madras∗ Department of Chemical Engineering, Indian Institute of Science, Bangalore-12 Abstract The effect of alkyl group substituents on the thermal degradation kinetics of poly (n-alkyl acrylate) was investigated in pyrolysis and in solution. The activation energie...

Polymer-based bioresorbable scaffolds (BRS) seek to eliminate long-term complications of metal stents. However, current BRS designs bear substantially higher incidence of clinical failures, especially thrombosis, compared with metal stents. Research strategies inherited from metal stents fail to consider polymer microstructures and dynamics--issues critical to BRS. Using Raman spectroscopy, we ...

We describe a means of chemical amplification to accelerate triggered degradation of a polymer and particles composed thereof. We designed a light-degradable copolymer containing carboxylic acids masked by photolabile groups and ketals. Photolysis allows the unmasked acidic groups in the polymer backbone to accelerate ketal hydrolysis even at neutral pH.

In vitro drug release and degradation mechanism of Poly (dl-lactide-co-glycolic acid)methoxypoly (ethyleneglycol) (PLGA-mPEG) microparticles were investigated under different pH conditions. Methotrexate(MTX), an antirheumatic drug, was employed as the model drug. In polyester-based microparticle system, two main issues involved in degradation were water uptake and the carboxylic groups produced...

The degradation mechanism of phosphorescent-dye-doped polymer light-emitting diodes ~PLEDs! is investigated. The active medium of our PLED is a polymer blend comprising poly~vinylcarbazole! ~PVK!, @2-~4-biphenylyl!-5-~4-tert-butyl-phenyl!-1,3,4-oxadiazole# ~t-PBD!, and platinum~II!-2,8,12,17-tetraethyl-3,7,13,18-tetramethylporphyrin ~PtOX!. The cyclic voltammetry result shows that the reductive...

A biodegradable poly(anhydride-ester) was synthesized by melt condensation polymerization of the acetylated monomer to yield a novel polymeric prodrug. The polymer we have synthesized is composed of alkyl chains linked by ester bonds to aromatic moieties, specifically salicylic acid--the active component of aspirin. With the medicinal properties attributed to salicylic acid and the ease of meta...

Oxidative stress is caused predominantly by accumulation of hydrogen peroxide and distinguishes inflamed tissue from healthy tissue. Hydrogen peroxide could potentially be useful as a stimulus for targeted drug delivery to diseased tissue. However, current polymeric systems are not sensitive to biologically relevant concentrations of H(2)O(2) (50-100 μM). Here we report a new biocompatible poly...

An Arthrobacter sp. isolated from a glucose-sucrose agar plate was found to produce a neutral, extremely viscous, opalescent extracellular polymer. Growth, polymer production, and rheological properties and chemical composition of the isolated polymer were examined. The polymer was found to be substantially different from other arthrobacter polymers. Some unusual properties included irreversibl...