An improved approach to poly(ester-carbonate) conjugates

A novel poly(ester-carbonate) (P(LA-co-NPC)) with activated pendant carboxyl groups was synthesized by ring-opening polymerization of L-lactide (LA) and 2-methyl-2-(4-nitrophenoxycarbonyl)-propylene carbonate (NPC) with diethyl zinc (ZnEt(2)) as catalyst. GPC and NMR studies confirmed the co-polymer structure. The pendant 4-nitrophenyl carboxylate groups can react with amino-containing molecules, such as 3,6,9-trioxa-1,11-undecanediamine, doxorubicin and chitosan under mild conditions. Therefore, any amino-containing molecules of biomedical interests can be conjugated to P(LA-co-NPC) efficiently and easily. The biocompatibility of the co-polymer was tested using L929 cell line, indicating that P(LA-co-NPC) is a promising biomedical material.