他克莫司阳离子微乳原位凝胶的制备及体外释放研究

目的 为了改善他克莫司水溶性差、眼部生物利用度低的问题，研制了他克莫司阳离子微乳原位凝胶，并研究其体外药物释放行为，为后期进一步研究提供基础。方法 通过高压均质法制得他克莫司阳离子纳米乳，并将其分散于泊洛沙姆407和泊洛沙姆188中制备他克莫司阳离子微乳原位凝胶。采用无膜溶出模型研究其体外释放行为。结果 采用玻璃瓶倒置法测定胶凝温度，筛选出最优凝胶基质处方为26%泊洛沙姆407和12%泊洛沙姆188；体外释药结果显示凝胶溶蚀速率是决定体外释药速率的关键。结论 成功制备了他克莫司阳离子微乳原位凝胶，其体外释药稳定，能满足眼用制剂要求，展现出良好的眼部应用前景。

Preparation and in vitro release of tacrolimus-loaded cationic nanoemulsion-based in-situ gel

Objective In order to improve the problems of poor water-solubility and low bioavailability of ocular tacrolimus, a cationic nanoemulsion in-situ gel of tacrolimus was developed and its drug release behavior in vitro was studied to provide a basis for further research.Methods Tacrolimus-loaded cationic nanoemulsion was prepared by high pressure homogenization and dispersed in poloxamer 407 and poloxamer 188 to prepare tacrolimus-loaded cationic nanoemulsion-based in-situ gel. The membraneless dissolution model was used to study the in vitro drug release behavior.Results The inverse glass bottle method was used to determine the gelation temperature. The optimal formulation of gel matrix was screened out as 26% poloxamer 407 and 12% poloxamer 188. The in vitro release results showed that the rate of gel dissolution determined the in vitro drug release.Conclusion Tacrolimus-loaded cationic nanoemulsion-based in-situ gel is successfully prepared. Its in vitro drug release is stable. It meets the requirement of ophthalmic formulation and shows good prospects for ocular application.