聚（L-乳酸）体内外降解相关性研究

摘要

目的：考察聚（ L-乳酸）（ PLLA）植入剂体内外降解特性黏数和失重变化的相关性。方法以辛酸亚锡为催化剂，通过直接缩聚法制备聚（ L-乳酸）（ PLLA）树脂，经精制得药用辅料；将药用辅料通过特定设备压制成空白植入剂，考察其在大白兔体内的降解情况，并与其在pH7．4的磷酸盐缓冲液的体外降解相比较。结果聚（ L-乳酸）植入剂样品降解后的特性黏数与降解时间（ wk）呈指数关系，失重百分率与降解时间（ wk）呈线性关系。结论体内的特性黏数与体外的特性黏数数值相近，体外失重比体内快。%Objective To investigate the correlation of intrinsic viscosity and weightlessness in vivo and in vitro degradation of poly ( L-lactic acid) (PLLA) implants.Methods Stannous octoate as a cataly,through polycondensation preparation of poly (L-lactic acid) (PLLA) resin,was refined to obtain a pharmaceutic excipient ,which was pressed into the blank implants by a particular device .We studied its characteristics of degradation in rabbits in vivo ,and compared with its degradation in phosphate buffer in vitro .Results In-trinsic viscosity of poly (L-lactic acid) was exponentially related to the degradation time (wk),while that weightlessness showed a linear correlation of the degradation time (wk).Conclusions The intrinsic viscosity numbers of poly (L-lactic acid) in vivo are similar to that in vitro.The weight of poly(L-lactic acid) reduces faster in vitro than that in vivo .