title: Synthesis, characterization and in vitro degradation of a new family of alternate poly(ester-anhydrides) based on aliphatic and aromatic diacids.
abstract: A new family of alternate poly(ester-anhydrides) containing aliphatic and aromatic diacids were synthesized. The dicarboxylic acids were obtained by derivatization of p-hydroxy benzoic acid at the hydroxy terminus with cyclic anhydride (adipic anhydride and succinic anhydride) and subsequently polymerized via the corresponding mixed anhydrides by melt polycondensation. DSC traces revealed that the polymers had low Tg (< 40 degrees C) and no crystallinity. The static contact angle measurements indicated that the poly(ester-anhydrides) were more hydrophobic than poly(D,L-lactide) and poly(adipic anhydride). In vitro degradation of the polymers was also investigated in pH 7.4 PBS at 37 degrees C. It was found that degradation rate of the poly(ester-anhydrides) increased with p-carboxy phenyl adipic monoester (CPA) content in the polymers and the degradation duration could be adjusted from ca. 20 days to ca. 2 months. Erosion curve of poly(p-carboxy phenyl adipic monoester anhydride) (PCPA) was characterized by a linear region of weight loss at nearly constant rate in the first 7 days (ca. 80% of weight loss) followed by a gradual decrease region. IR and SEM analysis showed that significant erosion of PCPA occurred in the outer layer and no apparent erosion could be seen in the inner layer of the degrading sample after 7-day degradation. The poly(ester-anhydrides) may be used as either anti-infective polymeric prodrugs or matrices for drug delivery.
authors.affiliation: Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, People's Republic of China.
authors.forename: H L
authors.initials: HL
authors.lastname: Jiang
authors.forename: K J
authors.initials: KJ
authors.lastname: Zhu
mesh_terms: D000143:Acids / Q000737:chemistry*; D000812:Anhydrides / Q000138:chemical synthesis* / Q000737:chemistry; D001672:Biocompatible Materials; D001673:Biodegradation, Environmental; D008855:Microscopy, Electron, Scanning; D011091:Polyesters / Q000737:chemistry*
chemical_list: D000143:Acids; D000812:Anhydrides; D001672:Biocompatible Materials; D011091:Polyesters