Formulation, optimization and characterization of candesartan cilexetil nanosuspension for in vitro dissolution enhancement

Abstract

According to Biopharmaceutical classification system (BSC), candesartan cilexetil (CC) is a class-II drug which has limited bioavailability mainly due to its low solubility. In order to enhance its solubility, a universal approach of making nanosuspension is been used in the present investigation. High pressure homogenization, controlled precipitation, media milling and high speed homogenization are the various approaches which are most widely used to produce the nanosuspension. Here, nanosuspension is formulated by combination of two approaches; high speed homogenization and media milling to expedite and ease the process. The polymers used to stabilized the nanoparticles were polyvinylpyrrolidone K-30 (PVP K- 30), poloxamer 407, HPMC E 50. To optimize the concentration of the polymer and surfactant the simplex lattice design is used. Various process parameters like homogenization speed, time, media milling cycle, drug to bead ration are optimized by changing one parameter at a time. The nanoparticles produced were of particle size less than 500 nm and were also found to be stable. The saturation solubility was enhaced more than 20 times than the bulk drug. The nanonization of the particles by combination of high speed homogenization and media milling is an effective method of enhancing in vitro dissolution of Candesartan cilexetil.