Abstract

Mucoadhesive microspheres have their own significant amongst the various sustained release drug delivery systems. The prolonged residence time of these delivery devices at drug absorption site results in steep concentration gradient and enhanced bioavailability. In this study, the mucilage of Isabgol husk was applied as polymeric backbone to develop gliclazide loaded microspheres by crosslinking with glutaraldehyde. The formulations were studied for surface morphology, swelling behavior, particle size, in vitro release, release kinetics, in vitro mucoadhesion and gamma scintigraphy in rabbits. The release of gliclazide from microspheres was controlled by swelling of crosslinked microspheres followed by diffusion. Gamma scintigraphic images acquired for microspheres retention in gastrointestinal track of rabbits indicated the residence of formulation upto 24 h after oral administration. Gliclazide retained its integrity in polymeric matrix of microspheres as observed by Fourier transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffractometry. The sustained release of gliclazide and prolonged retention of microspheres in gastrointestinal track disclosed the rationality of mucoadhesive Isabgol husk microspheres in controlling the hyperglycemia in diabetes.

摘要

粘膜粘附微球在各种缓释药物递送系统中具有其自身的重要意义。这些递送装置在药物吸收部位的延长停留时间导致陡峭的浓度梯度和增强的生物利用度。在这项研究中，Isabgol 壳的粘液被用作聚合物骨架，通过与戊二醛交联来开发格列齐特负载微球。研究了制剂的表面形态、溶胀行为、粒度、体外释放、释放动力学、体外兔的粘膜粘附和伽马闪烁扫描。格列齐特从微球中的释放通过交联微球的溶胀和扩散来控制。获得的微球在兔胃肠道中滞留的伽马闪烁扫描图像表明制剂在口服给药后长达 24 小时。通过傅里叶变换红外光谱、差示扫描量热法和粉末 X 射线衍射法观察到，格列齐特在微球聚合物基质中保持其完整性。格列齐特的缓释和微球在胃肠道中的长期滞留揭示了黏膜粘附性 Isabgol 壳微球在控制糖尿病高血糖方面的合理性。