Synthesis and Cytocompatibility of Biodegradable Poly (L-Lactide-r-5-Hydroxyl Trimethylene Carbonate) Copolymer

The biomedical applications of poly(L-lactide) (PLLA) were limited by its high crystallinity, hydrophobicity and lack of functional groups, which resulted in poor cell affinity. In this paper, L-lactide (85mol%) and 5-benzyloxy-trimethylene carbonate (BTMC) (15mol%) were copolymerized via ring-opening polymerization in the presence of stannous octanoate as catalyst. The copolymer was unprotected to receive poly(L-lactide-r-5-hydroxyl trimethylene carbonate) copolymer with functional hydroxyl pendant groups. The copolymer was characterized by H-1 NMR, FTIR, GPC, DSC, TGA and XRD. The results showed that the reactivity of BTMC monomer was lower than that of LLA in the copolymerization. Both the protected and unprotected copolymers were amorphous. C2C12 myoblasts were seeded on the copolymer films to evaluate the cytocompatibility of the copolymer. The adhesion, proliferation and spreading of cells on poly(L-lactide-r-5-hydroxyl trimethylene carbonate) films were much better than those on PLLA films. The cell affinity of PLLA was improved greatly after the functionalization.