Formulation, Development and Optimization of Nimodipine Nanosuspension for Improving Dissolution Characteristics

Abstract

Poorly water-soluble drugs such as nimodipine (NM) offer challenging problems in drug formulation as poor solubility is generally associated to poor dissolution characteristics and thus to poor oral bioavailability. In order to enhance these characteristics, preparation of nimodipine nanosuspension has been achieved using media milling technique. We investigated the nanoparticle formation of NM via considering the effects of drug-to-stabilizer ratio, stabilizer-to-stabilizer ratio and amount of beads (zirconium oxide) on the mean particle size, and dissolution properties of NM. It was observed that optimization of drug-to-stabilizer ratio, stabilizer-to-stabilizer ratio and amount of beads allowed the formation of nanosuspensions with a mean particle size of 279 nm. Differential Scanning calorimetry studies confirmed that there were no major changes in the melting peaks of NM unmilled and NM nanoparticles ie. the crystallinity of the drug was maintained after the particle size reduction suggesting that improved dissolution of NM nanosusensions could be attributed to reduction in particle size (<300nm).