头孢氨苄生物黏附缓释片的制备及体外评价

目的：制备头孢氨苄生物黏附缓释片,并对其体外黏附性能及释药特性进行评价。方法：以单因素考察法确定制备头孢氨苄生物黏附缓释片的最优处方,以自制黏附力测定装置测定优化处方所制缓释片的黏附力,以转篮法（转速100r·min^-1）测定其在1、2、4、8小时时的释放度,并对其释药过程进行动力学方程拟合以判断释药机制。结果：最优处方采用羟丙甲纤维素（HPMC K15M,6mg）为骨架材料,卡波姆（CP971P,20mg）为黏附材料,乳糖（18mg）为填充剂,头孢氨苄和硬脂酸镁分别为52.6mg和0.5mg。按优化处方所制的缓释片的黏附力为54.7g;在0.1mol·L^-1的盐酸溶液中1、2、4、8小时的释放度分别为30%、50%、70%和90%以上;体外释药符合Higuchi方程,释放机制为扩散和骨架溶蚀的协同作用。结论：该头孢氨苄生物黏附缓释片的处方工艺基本满足设计要求。

Preparation and in Vitro Evaluation of the Bioadhesive Cephalexin Sustained-release Tablets

Objective： To prepare the bioadhesive cephalexin sustained-release tablets and to evaluate its in vitro adhesion performance and release profiles. Methods： The formulation for preparing bioadhesive cephalexin sustained-release tablets was optimized by single-factor method. The adhesive force of the test tablets prepared by adopting the best formulation was measured by using the self-made adhesion device, and the releasing rates at 1,2, 4 and 8 h were determined by basket method. The releasing mechanism of cephalexin from the tablets was established by equation fitting of releasing kinetic model. Results： The best formulation consisted the following： HPMC K15M（6 mg） as the matrix materials, carbopol （CP 971P, 20 mg） as binding materials, Flowlac 100 （18 mg） as fillers, cephalexin（52. 6 mg）and magnesium stearate（0.5 mg）. The adhesive force of the test tablets was 54.7 g. The releasing rates at 1, 2, 4 and 8 h were 30%, 50%, 70% and more than 90%, respectively. The in vitro drug release conformed to Higuchi equation, and releasing mechanism was synergism of diffusion and erosion. Conclusion： The bioadhesive sustained-release tablets meet the general requirements of the design.