石杉碱甲-玉米醇溶蛋白微球释放特性的研究

Study on in vitro release of Huperzine A Loaded Zein Microspheres

目的建立石杉碱甲-玉米醇溶蛋白微球体外释放的测定方法,并考察载药微球的体外释放特性及影响因素。方法采用高效液相色谱法,色谱条件:色谱柱:ODS-C18色谱柱(4.6 mm×250 mm,5μm);流动相:pH2.5磷酸盐缓冲液-乙腈(86∶14,V/V);检测波长:310 nm;流速:1.0 mL·min-1;柱温:25℃;进样量:20μL。将石杉碱甲载药微球加以不同的释放介质,在摇床中振荡,定时取样并补以新鲜介质,高效液相色谱法测定石杉碱甲的累积释放率,并用不同释药模型对水为介质的释放结果进行拟合。结果建立的高效液相色谱法符合方法学要求,分别以零级、一级、Higuchi以及Ritger-Peppas方程对以水为介质的释药曲线进行拟合,相关系数分别为0.693 8、0.902 5、0.964 6和0.954 7。介质的pH和离子强度不同,药物的释放结果不同。结论石杉碱甲-玉米醇溶蛋白微球在水中的释放符合Higuchi模型,微球中药物的释放机制以扩散为主。不同的pH和离子强度主要是分别通过影响石杉碱甲的溶解度和玉米醇溶蛋白的相对疏水性来影响石杉碱甲从微球中的释放速率。

Objective The purpose of this study was to research the property and effect factors of the release of hu- perzine - zein microspheres in vitro. Methods An HPLC method was established to measure the concentration of HupA in the samples. The release of huperzine A - zein microspheres in vitro was test in different mediums with a shaking table and the samples were extracted at definite times. Several models were used to fit the release result to speculate the release mech- anism. Results The established method would be applied for the study of the in vitro release. The correlation value r of ze- ro order, first order, Higuchi and Rigter - Peppas was 0. 693 8,0. 902 5,0. 964 6 and 0. 954 7, respectively. The release rate of HupA from the microspheres was different when pH and the ionic strength changes. Conclusion The release mechanism of HupA - zein microspheres was most corresponded with Higuehi model. The result showed that HupA mainly diffuses from the microspheres. The pH value and ionic strength would affect the release rate of HupA due to the variations of the solubili- ty of HupA and the relative hydrophobicity of zein respectively.