聚氧乙烯骨架缓释片的处方及体外释药机制研究

Formulation Optimization and Release Mechanism in Vitro of Matrix Tablets with Polyox® Mixture

关键词:  聚氧乙烯  亲水凝胶骨架  缓释片  释药机制

Key words:  polyethylene oxide  hydrogel matrix  sustained release tablets  drug release mechanism

摘要:

目的 以聚氧乙烯(PEO)为亲水凝胶骨架制备缓释片剂，并考察其体外释药机制。方法 基于两种规格PEO的用量比与释药速率之间的关系，优化缓释片处方。通过考察片剂的体外释放度和溶蚀比探讨其释药机制，并对不同溶解度药物的体外释放行为进行比较。结果 缓释片体外释药速率与PEO用量比呈线性关系，所得优化处方在12 h内以接近恒速释药，其体外释药与溶蚀过程基本同步，且在所考察用量范围内不同溶解度药物的体外释放度相近。结论 PEO制成的亲水凝胶骨架片缓释性能良好，其体外释药是药物扩散和骨架溶蚀协同作用的结果。

Abstract:

OBJECTIVE To optimize the formulation of sustained-release tablets with Polyox^® mixture as hydrogel matrix and to study its release mechanism in vitro. METHODS The formulation was optimized based on the relationship between the ratio of Polyox^® mixture and the release rate. The release mechanism was studied by comparing the release ratio with the erosion ratio in vitro. The release profiles of drugs with different solubility were analyzed. RESULTS The drug release rate in vitro was linear with the ratio of Polyox^® N60K and WSR303. Drug release profile in vitro of the optimal formulation obeyed the zero-order release model within 12 h(r=0.992 5) and almost synchronized with its erosion profile. The release profiles of drugs with different solubility were similar at 20% of drug content. CONCLUSION The matrix tablets made of Polyox^® showed excellent properties in sustained drug delivery and its drug release mechanism consisted of drug diffusion and matrix erosion.