AISSMS College of Pharmacy, Kennedy Road, Pune, India.
Drug Dev Ind Pharm. 2009 Jul;35(7):834-42. doi: 10.1080/03639040802627421.
Various approaches have been used to retain the dosage form in stomach as a way of increasing the gastric residence time, including floatation systems; high-density systems; mucoadhesive systems; magnetic systems; unfoldable, extensible, or swellable systems; and superporous hydrogel systems.
The objective of this study was to prepare and evaluate floating microspheres of rosiglitazone maleate for the prolongation of gastric residence time.
The microspheres were prepared by solvent diffusion-evaporation method using ethyl cellulose and hydroxypropylmethylcellulose. A full factorial design was applied to optimize the formulation.
Preliminary studies revealed that the polymer:drug ratio, concentration of polymer, and stirring speed significantly affected the characteristics of microspheres. The optimum batch exhibited a prolonged drug release, remained buoyant for >12 hours, high entrapment efficiency, and particle size in the order of 350 microm.
The results of 32 full factorial design revealed that the concentration of ethylcellulose 7 cps (X(1)) and stirring speed (X(2)) significantly affected drug entrapment efficiency, percentage release after 8 h and particle size of microspheres.
为了延长胃内停留时间，提高药物生物利用度，人们研究了多种方法来保持药物剂型在胃内的状态，包括漂浮系统、高密度系统、黏膜黏附系统、磁系统、可展开、可拉伸或可膨胀系统以及超多孔水凝胶系统。
本研究旨在制备和评价马来酸罗格列酮漂浮微球，以延长胃内停留时间。
采用溶剂扩散-蒸发法，以乙基纤维素和羟丙甲纤维素为载体材料制备微球。采用完全析因设计优化处方。
初步研究表明，聚合物与药物的比例、聚合物浓度和搅拌速度对微球的性质有显著影响。最优批次微球具有延长的药物释放、>12 小时的持续漂浮、高包封效率和 350μm 左右的粒径。
32 次完全析因设计的结果表明，乙基纤维素 7cps（X1）的浓度和搅拌速度（X2）显著影响药物包封效率、8 小时后的释放百分比和微球的粒径。
