| A novel composite film was investigated to repair nerve defect. Poly[LA-(Glc-Lys)] with side-chain amino groups was synthesized firstly. Then the copolymer was physical mixed with B-tricalcium phosphate powder to prepare composite film which has good cytocompatibility.3S-[Ne-(benzyloxycarbonyl)-L-lysyl]-2,5-morpholinedione was prepared in 31％yield by cyclization of Na-Bromoacetyl-lys(Z)which was obtained by Ne-(benzyloxy-carbonyl)-L-lysine and bromoacetyl bromide. Poly (LA-co-(Glc-alt-Ne-benzyloxy-carbonyl-L-Lys)) was synthesized by ring opening copolymerization of D, L-lactide with 3S-[Ne-(benzyloxycarbonyl)-L-lysyl]-2, 5-morpholinedione for the first time. The copolymers were characterized with FT-IR, 1H-NMR and 13C-NMR. The results showed that Ne-(Carbonylbenzoxy)-L-lysine was introduced into the main chain of PDLLA. And the composition of the copolymer can be adjusted according to the ratio in feed. However, the ratio of the 3S-[Ne-(benzyloxycarbonyl)-L-lysyl]-2, 5-morpholinedione in copolymer is less than that in feed. And the yield was reduced when the 3S-[Ne-(benzyloxycarbonyl)-L-lysyl]-2, 5-morpholinedione in feed was increased. The deprotection of benzyloxycarbonyl group was accomplished by catalytic hydrogenation with Pd/C as a catalyst. 1H-NMR indicated that the protective group of the polymer was removed completely.Composite film was prepared by solvent volatilization method and the ultrasonic dispersal technique under 20℃and 40％humidity, using dichloromethane as solvent to confect polymer solution with 10％concentration, addingβ-TCP powder which the grain size was less than 63μm, content ratio was fixed at 5％. The composite film was observed by SEM. The results showed that the surface of poly[LA-(Glc-Lys)]/β-TCP composite film was rougher than that of PDLLA/B-TCP film.Olfactory ensheathing cells were co-cultured with poly[LA-(Glc-Lys)]/β-TCP film and PDLLA/β-TCP film to evaluate their OECs-compatibility and potential to be used as biomaterial. The cell adhesion experiment, the MTT assay and the immunofluorescence showed that the poly[LA-(GIc-Lys)]/β-TCP film is superior in cell adhesion and cell growth to PDLLA/β-TCP film, and theβ-TCP can support the OECs adhesion and promote the growth of OECs. Poly[LA-(Glc-Lys)]/β-TCP composite has good cytocompatibility. It's potential to be a kind of ideal biomaterial used for nerve repair.
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