Preparation and In-Vitro Evaluation of Clopidogrel Bisulfate Liquisolid Compact

Abstract

Liquisolid (LS) compact is the most promising technique for increasing dissolution rate and consequently the bioavailability of poorly soluble drugs. Clopidogrel is an oral antiplatelet used for treatment and prophylaxis of cardiovascular and peripheral vascular diseases related to platelets aggregation. Clopidogrel has low solubility at high pH media of the intestine and low oral bioavailability (about 50%). The purpose of this work was to enhance the dissolution pattern of the clopidogrel through its preparation as liquisolid compact. A mathematical model was used to calculate the optimum quantities of Tween 80 as non- volatile liquid vehicle, Avicel PH 102 as carrier material and Aerosil 200 as coating material needed to prepare acceptably flowing and compactible powder mixtures. The liquisolid compacts were evaluated for hardness, friability, weight variation, content uniformity, and disintegration time and in-vitro drug release rate. In addition, Differential Scanning Calorimetry (DSC), Fourier Transforms Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) were used for the assessment of the physicochemical properties of the drug and compatibility with excipients in liquisolid compacts. Twelve formula were prepared and the selected formula (LS-2) containing (50% w/w) clopidogrel in Tween 80 at the excipient ratio (R) of (20:1). Compact of (LS-2) released (92.2%) of drug during the first 10 minutes compared to (13.6%) of the directly compressible tablet and (24.2%) of marketed tablet (Plavix®). In conclusion, the dissolution rate of clopidogrel can be enhanced to a great extent by liquisolid technique in comparison to conventional tablets.