中文摘要：

应用反相乳液分散-离子键合法，以戊二醛（GD）为交联剂制备负载拉米夫定的海藻酸钠／壳聚糖微球（LAMV-SALG／CS）．利用拉米夫定的氨基与海藻酸钠的羧基形成弱酸弱碱盐键，使该药物被稳定包覆在微球内层，再以交联壳聚糖作为微球外层而形成具有核壳结构的复合微球．对微球的理化性质及释药性能进行表征及研究．结果表明，制备的LAMV-SALG／CS微球形貌规整，平均粒径约为2μm．测得微球载药质量分数为11．6％，药物包封率为70．3％；CS的活性氨基和戊二醛的羰基结合，形成交联网络，药物被包覆在微球中，且以单分子形式存在．体外模拟释放结果表明，微球释药性能良好，释药平缓，在酸性介质中累积释药率为27％时，其释药周期长达82h；随制备微球时SALG浓度增大，药物释药速率减缓；在酸性介质中释．药速率大于碱性介质；碱性介质合成的微球其释药速率快于弱酸性和弱碱性介质中合成的微球．

英文摘要：

With glutaraldehyde as cross-linking agent, LAMV-SALG/CS microspheres were prepared by means of the inverse emulsion dispersion and ionic bonding. The amino of lamivudine and carboxyl of sodium alginate can form weak salt bonds, so the drug can be stably wrapped in the inner layer of the microspheres, and then chitosan was crosslinked by glutaraldehyde to form the shell layer of the composite microspheres. The physicochemical properties and the drug-release performances of the microspheres were investigated. The microspheres have a regular spherical shape and an average diameter of about 2 μm. The drug mass content was 11.6% , and the drug encapsu- lation efficiency reached to 70. 3 %. The amino groups in chitosan combined with the carbonyl group in glutaraldehyde to form the cross-linked network, and lamivudine have been enwrapped inside the microspheres. The drug-release measurement results indicated that the microspheres have a satisfactory performance of releasing lamivudine at slow and steady rate. The drug release period corresponding to cumulative drug-release rate of 27% reached to 82 h in the acid medium. With the increase of the concentration of SALG, the releasing rate of lamivudine decreased. The releasing rate of lamivudine in acidic buffer was faster than in alkaline one. Drug-releasing rate of the microspheres prepared in the alkaline reaction medium was faster than that prepared in weak alkaline and acid ones.