DEVELOPMENT OF TOLCAPONE INCORPORATED SELF- MICRO EMULSIONS FOR SOLUBILITY AND BIOAVAILABILITY ENHANCEMENT

Abstract

For BCS Class II and IV compounds, the main formulation objective is to increase the aqueous solubility of the API in the gastro - intestional fluids and maintain it in a solubilized state until it reaches the site of absorption. Lipid-based formulations including self-emulsifying formulations offer the potential for enhancing the absorption of poorly soluble and/or poorly permeable compounds. Self micro emulsion preparations are a obtained by a simple technique, with optimization of the composition based upon the ternary phase diagram. Tolcapone is an anti Parkinson agent, a poorly soluble drug, which is dissolved in the composition of oil and lipid mixture. Self micro emulsions are characterized by solubility study, particle size analysis, in vitro dissolution and in vivo bioavailability. The development of self micro emulsion formulations begins with the screening of excipients with the API in order to identify those that provides the best solubilization and chemical compatability. Particle size of the self micro emulsions below the 50 microns and the dispersive capacity of the multicomponent self micro emulsion gives homogenous emulsion in contact with aqueous media. In vitro drug release study showed that tolcapone self microemulsions increased in dissolution as compared to unformulated tolcapone drug and marketed product. In vivo increased absorption of the tolcapone micro emulsion formulation is 8.65 fold compared to the plain tolcapone and 1.07 fold compared to the marketed product.