Today, research and development on biodegradable and biomedical polymers are expanding in both polymer and biological sciences. Students with a background in organic chemistry and biology will gain experience in the preparation and characterization of suitable polymers, and in biological procedures used to monitor biodegradation and biocompatability.

Biodegradable Plastics:
Efforts to use biodegradable materials have been initiated to reduce the environmental impact of plastic wastes. Several of these biodegradable materials are polyesters, and they have attracted much industrial attention as "green thermo-plastics." Most notable are poly(3-hydroxybutyrate), PHB, and poly(lactic acid), PLA. They have brittle properties as room temperature and it is desirable to improve their physical properties by copolymerization and/or blending with other polymers.

Undergraduate research students have prepared polymer blends containing PHB and its copolymers, and have carried out systematic studies of their biodegradation by a variety or microorganisms. Characterization of the blends pre and post degradation is carried out using SEM, DSC, FTIR, and FTNMR. Similar studies on PLA and isolation of specific enzymes responsible for degradation will be carried out this year.
 

Biomedical Polymers:
Biomedical polymers are widely used as replacements for heart valves, tissue, hip joints and blood vessels. Polyurethanes show potential as replacements for small diameter blood vessels, particularly required by patients suffering from vascular disease resulting from complications of diabetes. Suitable replacement vessels could prevent the thousands of amputations performed each year in the United States.

Undergraduate research students have synthesized two types of block copolyether-urethane-ureas (PEUU's) and are investigating their biocompatability. Protein adsorption, more specifically albumin adsorption, was studied using the Bradford Assay, the Hartree-Lowry Assay, and gel electrophoresis (SDS-PAGE). The surface of the PEUU's will be studied using attenuated total reflectance infra red spectroscopy (ATR-IR) and SEM.