Stability and depolymerization of poly(sebacic anhydride) under high moisture environment

Polyanhydrides are found to be useful in drug delivery systems; however, these aliphatic polyanhydrides are also unstable under humidity and temperature (greater than 0degreesC) for their low toxicity and surface eroding mode of drug release. In this research, poly(sebacic anhydride) was synthesized for a stability and depolymerization study in high humidity a surrounding temperature of 35degreesC. According to the results from gel permeation chromatography, IR spectrophotometry, and differential scanning calorimetry investigations, it was found that both self-depolymerization and hydrolysis mechanisms existed during the depolymerization process for poly(sebacic anhydride) and they can be monitored directly. These results were further compared with previous research in a depolymerization study of polyanhydrides in a vacuum and in buffer solution. (C) 2003 Wiley Periodicals, Inc.