Krishnaiah Y S, Veer Raju P, Dinesh Kumar B, Bhaskar P, Satyanarayana V
Pharmaceutical Technology Division, Department of Pharmaceutical Sciences, College of Engineering, Andhra University, Visakhapatnam 530 003, India.
J Control Release. 2001 Nov 9;77(1-2):87-95. doi: 10.1016/s0168-3659(01)00461-8.
The objective of the present study is to develop colon targeted drug delivery systems for mebendazole using guar gum as a carrier. Matrix tablets containing various proportions of guar gum were prepared by wet granulation technique using starch paste as a binder. The tablets were evaluated for drug content uniformity, and were subjected to in vitro drug release studies. The amount of mebendazole released from the matrix tablets at different time intervals was estimated by a high-performance liquid chromatography method. Guar gum matrix tablets released 8-15% of the mebendazole in the physiological environment of stomach and small intestine depending on the proportion of guar gum used in the formulation. When the dissolution study was continued in simulated colonic fluids the matrix tablets containing 20% of guar gum released another 83% of mebendazole after degradation into 2-3 pieces. The matrix tablets containing 30% of guar gum also released about 50% of mebendazole in simulated colonic fluids indicating the susceptibility of the guar gum formulations to the rat caecal contents. The results of the study show that matrix tablets containing either 20% or 30% of guar gum are most likely to provide targeting of mebendazole for local action in the colon. The mebendazole matrix tablets containing either 20% or 30% of guar gum showed no change either in physical appearance, drug content or dissolution pattern after storage at 45 degrees C/75% relative humidity for 3 months. Differential scanning calorimetry indicated no possibility of interaction between mebendazole and guar gum.
本研究的目的是开发以瓜尔胶为载体的甲苯达唑结肠靶向给药系统。采用淀粉糊作为黏合剂，通过湿法制粒技术制备了含有不同比例瓜尔胶的骨架片。对片剂进行了药物含量均匀度评价，并进行了体外药物释放研究。采用高效液相色谱法测定了不同时间间隔从骨架片中释放的甲苯达唑量。根据制剂中瓜尔胶的比例，瓜尔胶骨架片在胃和小肠的生理环境中释放8%-15%的甲苯达唑。当在模拟结肠液中继续进行溶出度研究时，含有20%瓜尔胶的骨架片在降解成2-3片后又释放了83%的甲苯达唑。含有30%瓜尔胶的骨架片在模拟结肠液中也释放了约50%的甲苯达唑，表明瓜尔胶制剂对大鼠盲肠内容物敏感。研究结果表明，含有20%或30%瓜尔胶的骨架片最有可能使甲苯达唑靶向作用于结肠局部。含有20%或30%瓜尔胶的甲苯达唑骨架片在45℃/75%相对湿度下储存3个月后，其外观、药物含量或溶出模式均无变化。差示扫描量热法表明甲苯达唑与瓜尔胶之间不存在相互作用的可能性。
