The Synthesis and Biodegradability of Poly(lactide-random-depsipeptide)-PEG-Poly (lactide-random-depsipeptide) ABA-type Triblock Copolymers

摘要

Amphiphilic ABA-type triblock copolymers were synthesized to develop a biodegradable anti-adhesive membrane.In this particular synthesis, poly[L-lactide(LA)-co-depsipeptide] (poly[LA-co-(Glc-Leu)]:PLGL) was used as the A segment,and the poly(ethylene glycol)s (PEG)s,Mn=10,000 and Mn=20,500 were used as the B segment.The synthesis of the triblock copoly- mer (PLGL-PEG-PLGL) was carried out via a ring-opening copolymerization of L-lactide and cyclo(Glc-Leu) in the presence of hydroxytelechelic poly(ethyl- ene glycol) using tin 2-ethylhexanoate as a catalyst.To evaluate the copolymer films as candidates for biodegradable anti-adhesive membranes,physicochemi- cal properties such as degradation on behavior under physiological conditions and water absorption were investigated.The degradation rate of the PLGL- PEG-PLGL films varied with changes in the molecular architecture;specifi- cally,the molecular weight of the hydrophilic B segment and the depsipeptide unit content in the A segment were more prominent.The biocompatibility and resorption of the PLGL-PEG-PLGL films were also evaluated.The PLGL- PEG-PLGL films were degraded and depleted gradually in vivo without inflam- mation.