Patil J S, Kamalapur M V, Marapur S C, Shiralshetti S S
Department of Pharmaceutics, B. L. D. E. A.'s College of Pharmacy, B. L. D. E. University campus, Bijapur-586 103, India.
Indian J Pharm Sci. 2011 Sep;73(5):504-9. doi: 10.4103/0250-474X.98988.
Prolonged release drug delivery system of stavudine was made by ionotropic gelation and polyelectrolyte complexation technique. Cross-linking reinforced chitosan-gellan complex beads were prepared by gelation of anionic gellan gum, the primary polymer, with oppositely charged counter ion to form beads which were further complexed with chitosan as a polyelectrolyte. The effect of this polymer on release profile of drug was studied. Beads without chitosan complexation were also made. The reaction of chitosan-gellan complex dominates the formation of skin layer on the surface of beads. Stavudine an antiretroviral drug was selected as novel drug for the experiment. The final formulations were subjected to in vitro evaluation and several characterization studies. Batches with gellan gum shows Higuchi model, while chitosan-gellan shows zero order release. All the batches with copolymer showed sustained the drug release more than 12 h, whereas with gellan gum alone showed up to 10 h. Batches with chitosan showed maximum drug encapsulation efficiency.
司他夫定的长效药物递送系统是通过离子凝胶化和聚电解质络合技术制备的。通过阴离子结冷胶（主要聚合物）与带相反电荷的抗衡离子凝胶化制备交联增强的壳聚糖-结冷胶复合珠，形成珠子后再与作为聚电解质的壳聚糖进一步络合。研究了这种聚合物对药物释放曲线的影响。还制备了未与壳聚糖络合的珠子。壳聚糖-结冷胶复合物的反应主导了珠子表面皮层的形成。选择抗逆转录病毒药物司他夫定作为实验的新药。对最终制剂进行了体外评估和多项表征研究。含结冷胶的批次呈现 Higuchi 模型，而壳聚糖-结冷胶呈现零级释放。所有含共聚物的批次药物释放持续超过12小时，而仅含结冷胶的批次药物释放持续长达10小时。含壳聚糖的批次显示出最大的药物包封效率。
