延胡索乙素胃漂浮微球的体外漂浮及释药特征评价

In Vitro Evaluation of Release and Floating of Tetrahydropalmatine Gastric Floating Microsphere

关键词:  延胡索乙素  胃漂浮微球  释放特征  漂浮性能

Key words:  tetrahydropalmatine  gastric floating microsphere  release characteristics  floating performance

摘要:

目的 制备延胡索乙素(tetrahydropalmatine，THP)胃漂浮微球，考察THP胃漂浮微球在不同条件下的体外漂浮性能与释药特征。方法 采用乳化溶剂挥发法制备THP胃漂浮微球，模拟胃肠道环境，通过直接观察法考察THP胃漂浮微球在0.1 mol·L^-1盐酸溶液、pH 3.0 PBS、pH 4.5醋酸缓冲液、pH 6.8 PBS释放介质，50，100，150 r·min^-1转速条件下的漂浮性能；采用转篮法考察THP胃漂浮微球在上述释放条件下的体外释放特征；以罗通定片为参比制剂，比较两者在模拟胃酸环境的体外释放特征；采用常见的动力学模型拟合延胡索乙素胃漂浮微球的释药曲线。结果 THP胃漂浮微球在不同介质中均能立即起漂，持漂12 h，漂浮率为100%；在4种释放介质中12 h累积释放度分别为(90.55±4.65)%，(81.48±5.92)%，(66.24±3.00)%，(51.93±2.35)%；在3种转速下，12 h累积释放度分别为(84.26±3.22)%，(90.55±4.65)%，(94.70±2.15)%。在模拟胃酸环境(0.1 mol·L^-1盐酸溶液)下，罗通定片0.5 h累积释放度为(78.31±11.01)%，2 h基本释放完全，而THP胃漂浮微球12 h内释药速度平稳而缓慢，无突释现象，且释药完全。结论 该研究制备的THP胃漂浮微球体外漂浮性能较好，具有较好的缓释效果，其体外释放行为符合Higuchi方程。

Abstract:

OBJECTIVE To prepare tetrahydropalmatine(THP) gastric floating microsphere and investigate in vitro release characteristics and flotation performance of THP gastric floating microsphere in different conditions. METHODS Prepared THP gastric floating microsphere by emulsion-solvent diffusion method. The flotation performance of THP gastric floating microsphere was investigated by direct observation in the release medium of 0.1 mol·L^-1 hydrochloric acid solution, pH 3.0 PBS, pH 4.5 acetic acid buffer, and pH 6.8 PBS, and under different speeds in 50, 100, 150 r·min^-1, which was simulated gastrointestinal tract environment. To investigate in vitro release characteristics of THP gastric floating microsphere by rotating basket method of the above release conditions. Taking the rotundine tablets as reference, compared their release behavior in vitro in evaluated gastric acid environment. RESULTS In the different release conditions, THP gastric floating microsphere could immediately float 12 h, its floating rate was 100%. The accumulative release rate after 12 h in the different release medium were (90.55±4.65)%, (81.48±5.92)%, (66.24±3.00)%, (51.93±2.35)%, and in the different speeds were (84.26±3.22)%, (90.55±4.65)%, (94.70±2.15)%. The accumulative release rate of the rotundine tablets was (78.31±11.01)% in 0.5 h in the gastric acid environment (0.1 mol·L^-1 hydrochloric acid solution), and almost finished in 2 h. Meanwhile, THP gastric floating microspheres had a good in vitro floating performance and sustained release effect, and finished release totally without phenomenon of sudden release. CONCLUSION THP gastric floating microspheres has a good in vitro floating performance and sustained release effect. Its in vitro release behavior conforms to the Higuchi equation.