Abstract:
The objective of present study was to develop Gastroretentive floating microballoons of Labetalol Hydrochloride in order to achieve an extended retention in the upper GIT, which may result in enhanced absorption and thereby improved bioavailability. Gastroretentive Floating microballoons of Labetalol hydrochloride were prepared by emulsion solvent diffusion method using Ethyl Cellulose and Eudragit RS100 in varying compositions and ratios. The percentage yield, particle size, Scanning Electron Microscopy (SEM),in vitro buoyancy, drug entrapment efficiency, in vitro drug release, release kinetics and Stability studies were studied. The optimized formulation was filled in capsules and post formulation parameters of capsules were performed. Percentage yield of all formulations was in the range of48.33-86.25 %. The particle size of all formulations was distributed between 55.4µm – 219.33µm.Drug entrapment efficiency was in the range of80.5 to 97.2%, and in vitro buoyancy percentage was in the range of 76 – 94%. The best drug release profiles were seen with formulation F3 and F8 at the end of 12hrs.Scanning electron microscopy confirmed their spherical and circular shape with smooth surface. The release kinetics of the optimised formulation showed zero order kinetics. Stability studies indicated that the formulation is stable as per ICH guidelines. The data obtained in this study suggest that Gastroretentive floating microballoons of Labetalol Hydrochloride are promising for controlled drug delivery. It also shows that as increase in drug: polymer ratio affects the particle size, in vitro buoyancy and drug release.

Keywords: Labetalol Hydrochloride, Floating Microballoons, Hollow Microspheres, Controlled Release, Floating Microspheres, Gastroretentive Drug Delivery.