FORMULATION DESIGN AND IN VITRO CHARACTERIZATION OF FELODIPINE NANO-SUSPENSION

Felodipine is a member of the dihydropyridine class of calcium channel antagonists (calcium channel blockers) and is insoluble in water. To counter act above side effects, to enhance bioavailability of felodipine in blood stream and to make drug to more targeting, felodipine drug is being designed as nanosuspension formulation using hydroxyl propyl methyl cellulose and hydroxyl propyl cellulose as surfectants as well as rate controlling polymer. Drug polymers interactions were studied by FT-IR spectroscopy. Precipitation method has been used to prepare nanosuspension particles of poorly soluble drug. The prepared nanosuspensions were characterized for droplet size, pH, viscosity, polydispersity index, refractive index, surface morphology study by Scanning Electron Microscopy (SEM), drug content, percentage transmittance, zeta potential, in vitro skin permeation and drug release kinetic studies. The droplet size was in the ranges of 61.2±0.58 (F3) to 91.4±0.79 nm (F5). The polydispersity index of various felodipine nanosuspension formulations was in the ranges of 0.271±0.14 to 0.651±0.21. 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.