MOLECULAR DESIGN OF BIOLOGICALLY-ACTIVE BIODEGRADABLE POLYMERS FOR BIOMEDICAL APPLICATIONS

The objective of this research is to synthesize synthetic biodegradabl e polymers that would have biological functions similar to nitric oxid e. Polyglycolide (PGA) was the synthetic biodegradable polymer and 4-a mino-2,2,6,6-tetramethylpiperidine-1-oxy (Tempamine) was chosen as the source of nitroxyl radicals. Tempamine nitroxyl radicals were chemica lly incorporated into the carboxylic acid chain ends of PGA macromolec ules via amide linkage. The kinetics of in vitro hydrolytic release of Tempamine nitroxyl radicals from the host PGA in buffered media at 37 degrees C was studied. Tempamine nitroxyl radicals were released into the media via cleavage of either ester linkages in the PGA segments o r/and the amide linkage between Tempamine and the PGA segments. The du ration of hydrolysis would determine the type of degradation products that were different in the segmental length of the PGA component. A pr eliminary in vitro cell culture study of this new generation of biolog ically active biodegradable polymers indicated that it was able to ret ard the proliferation of smooth muscle cells as pure nitric oxide does .