Extended Release Floating Microballoons Containing Clerodendrum colebrookianum Extract: in vitro in vivo Evaluation

Abstract:

Aims: Microballoons are floating particulate system comprising of a hollow core, drug being loaded within the polymeric layer. The aim of the study was to prepare microballoons containing extract of Clerodendrum colebrokianum, as bioactive agent. Methods: The microballoons were prepared by solvent diffusion technique, prepared microballoons were physico-chemically characterized (Scanning Electron Microscopy (SEM), buoyancy determination, entrapment efficiency, etc), in vitro drug release study and estimated for its in vivo antihypertensive activity by 2K1C hypertension induction method. Results: SEM confirmed the microballoons to be spherical with porous surfaces and hollow core. The developed formulation showed a buoyancy varying from 70.18%-89.90%. The entrapment efficiency of bioactives in microballoons was found between 52%-69% with a delayed release of maximum 28% in 8 hr as found from in vitro drug release study. In vivo antihypertensive studies carried out in rat model showed C. colebrookianum extract have good antihypertensive activity in both high and low dose with respect to standard propanolol. The formulations containing both doses were further found to be effectual in the treatment of hypertension because of its floating nature. Conclusion: The results suggested that optimized formulation show an effective extended release of Clerodendrum colebrokianum extract for the treatment of hypertension.

Key words: Microballoons, Antihypertensive agent, Encapsulation, Floating drug delivery system, 2K1C hypertension induction method.