Design and In-Vitro Evaluation of Gastro Retentive Floating Microbeads of Zidovudine Hydrochloride
The present work is an attempt to prepare floating microbeads of Zidovudine as model drug to achieve an extended retention in upper GIT which results in enhanced absorption, thereby improves bioavailability and avoiding multiple dosing for hospital acquired infections. In the present investigation, microbeads were prepared by ion-gelation method using polymers like sodium alginate, hydroxy propyl methyl cellulose (K100M), gas forming agent like sodium bicarbonate, and curing agents such as calcium chloride and Barium chloride solutions. Prepared microbeads were evaluated for micromeritic property, particle size and morphology, in-vitro buoyancy study, drug loading and encapsulation efficiency and in-vitro drug release kinetic studies. All the formulations produced optimal flow properties as represented in terms of compressibility. Result showed barium chloride cross linked formulations showed the excellent flow ability as compared to calcium chloride cross linked formulations. SEM study revealed irregular surfaces with pores. The alginate floating microbeads were shown good floating ability. The prepared microbeads exhibited prolonged drug release for 12 hrs and remained buoyant up to 8 hrs. Barium chloride linked microbeads showed better drug release of 91.78 percentage and drug content of 87.14 percentages as compared to calcium chloride linked. Thus, it can alternatively be used to avoid multiple dosing, thereby reducing the chance of dose dumping.