Improved dissolution rate of Atorvastatin calcium using solid dispersions with PEG-4000

Lakshmi Narasaiah.V, Kalyan Re

Abstract

The solid dispersion was defined as the dispersion of one or more active ingredients in an inert carrier or matrix. The purpose of the study was to improve the physicochemical properties of Atorvastatin calcium (ATC) like solubility, dissolution properties and stability of poorly soluble drug by forming dispersion with PEG 4000 as water soluble carrier. ATC was formulated by physical mixtures and solid dispersions (dropping method) using 1:1, 1:2 and 1:3 ratios of drug and carrier (PEG 4000). The Phase and saturation solubility study, in vitro dissolution of pure drug, physical mixtures and solid dispersions were carried out. The prepared dispersions showed PEG was found to be effective in increasing the saturation solubility and dissolution rate of ATC than that of pure drug. The dispersion with PEG 4000 (1:3) by dropping method showed faster dissolution rate (85.038%) as compared to other dispersions with PEG 4000 (1:1 and 1:2) whichever prepared by physical mixture and dropping method. The FT-IR shows the complexation and there were no interactions. Finally solid dispersion of ATC: PEG 4000 prepared as 1:3 ratio by dropping method showed excellent physicochemical characteristics and was found to be described by dissolution release kinetics and was selected as the best formulation in this study.