Effect of Vehicles on Release of Meloxicam from Various Topical Formulations

Abstract

This article evaluates the effect of various vehicles (O/W, W/O and two W/O/W emulsions and a hydrogel) on meloxicam release. One of W/O/W emulsions was named W/O/W-C containing Carbopol ® 934 as a gelling agent in its outer aqueous phase. Release of drug through cellulose acetate membrane was studied by using Franz-type diffusion cells. Hydrogel formulation gave the highest release with a significant difference followed by W/O/W, O/W, W/O/W-C and W/O emulsions. Increase in amount of oil phase resulted in slower drug release strictly indicating importance of lipophility of vehicle on release of lipophilic drugs like MX. Incorporation of MX in hydrogel increased the released amount by up to 20 times when compared with the other formulations. Increase in viscosity of the formulations was also followed the same order. Release study was performed by using UV spectroscopy. Furthermore, the determination method of MX was validated through the following performance criteria: linearity, intra-day and inter-day precision, accuracy, specifity and recovery. This method was proved as precise and accurate determination of MX in multi-component pharmaceutical preparations besides colorimetric methods.