Nanosuspension – Preparation,In VitroandEx VivoEvaluations of Felodipine Hydrochloride

Abstract

Felodipine is a member of the dihydropyridine class of calcium channel antagonists (calcium channel blockers) and is insoluble in water. The main objective of this study to design a nanosuspension formulation using hydroxyl propyl methyl cellulose and hydroxyl propyl cellulose. Drug polymers interactions were studied by Differential Scanning Colorimetry. Precipitation method has been used to prepare nanosuspension particles of poorly soluble drug. The prepared nanosuspensions were characterized for droplet size, pH, viscosity, refractive index, surface morphology by Transmission Electron Microscopy (TEM), drug entrapment efficiency, zeta potential, in vitro skin permeation, drug release kinetic, histopathological and stability studies. The droplet size was in the ranges of 61.2±0.58 (F3) to 91.4±0.79 nm (F5). Most nanosuspension possesses a very low viscosity and, therefore, their application may be convenient. The pH value of all the felodipine nanosuspension formulation was in the skin pH range, which was nearer to neutral pH range, demonstrating that all the felodipine nanosuspension will be non toxic, non irritating and non allergic. The felodipine nanosuspension formulation F3 containing 0.75% HPMC K4M, could be concluded as the best optimized formulation for safe management of hypertension. The optimized felodipine nanosuspension formulation F3 was found to be stable for both short and long term period in various storage conditions. Skin irritation test revels that no erythema was observed on visual inspection after application of felodipine nanosuspension formulations on rat skin. Thus, the developed formulation is non-sensitizing and safe for use.