氨基酸共聚物缓释片和胶囊的制备及体外释药研究

Sustained drug-release tablets and capsules of amino acid copolymers: preparation and in vitro studies

本研究由可生产降解的氨基酸共聚物（白氨酸－谷氨酸甲酯－谷酸三元共聚物）制成缓释药片和缓释胶囊，并对不同药物（左旋１８－甲基炔诺酮，黄体酮，氟尿嘧啶）和不同共聚物配比（摩尔比为３０：５０：１５，３０：４５：２５，３０：３２：３８）的缓释药片，胶囊进行体外释药试验，时间最长达２００ｄ，定期用分光光度计测定释药速率随时间增长而缓慢减小，释药速率均随药物在释药介质中的溶解度大而增大。

Poly-α-amino acids (leucine, methyl glu-tamate and glutamic acid copolymers) wereused for preparation of sustained drug-releasetablets and capsules. In vitro drug release be-have of these devices with drugs (L-norgestrel, progesterone and fluorouracil) andpoly-α-amino acids (Leu: GluOMe: GiuOHmole perent 30: 55: 15, 30: 45: 25 and 30:32: 38 respectively) was studied. Capsuleswere composed of a copolymer sheath sur-rounding the drug. Tabelets were prepared bycompression molding the mixed powder ofdrug and copolymer. Released drugs in 37±1C saline were detected with UV spectropho-tometer. Our results showed that the two drugdelivery deices could release drugs for a longtime (over 200 days). The drug release rateincreased with an increase in solubility of drugand mole percent of glutamic acid within thecopolymers. The release rate of capsules wasrelatively constant and was not related to re-lease time. The release rate of tabelets slowlydecreased with the prolongation of releasetime after an initial burst.