Formulation and in vitro and in vivo characterization of Nifedipine stabilized nanosuspensions by nanoprecipitation method

Abstract

Nifedipine is a dihydropyridine calcium channel antagonist originally introduced for the treatment of angina pectoris and hypertension. Nifedipine which is a poorly water soluble drug coming under BCS class-2, however it suffers from a poor aqueous solubility, which delays its onset of action. Therefore, the purpose of the present study is to utilize the nanotechnology to formulate nanoparticles that enhance the dissolution and hence the bioavailability nifedipine. Nanosuspensions were prepared by nano precipitation method in the presence of selected stabilizers at different concentrations. The nanosuspensions were evaluated for their particle size, zeta potential, drug content and In vitro drug dissolution. The selected formula was freeze dried and characterized by scanning electron microscopy (SEM), fourier transforms infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and pharmacokinetic study. The in vitro dissolution showed higher drug release compared to the pure drug. The optimum formula has an average particle size of 225.56±4.65 nm and zeta potential of -17.84±2.17 mV. The bioavailability parameters in the rabbits were enhanced by 2 folds when compared with the marketed tablets (Calcigard®). Nanoprecipitation method was successfully employed to produce stable Nifedipine nanosuspension by using the suitable concentration of stabilizer (PVA, Tween 80, PVP & HPMC). From this study, it is concluded that formulation of Nifedipine nanosuspension may be a promising approach that improves the dissolution rate and hence oral bioavailability.