Formulation and Evaluation of Cassia tora Phytosomal Gel Using Central Composite Design

Abstract

Cassia tora has been classified as an antifungal agent, but no optimized formulation for improved drug penetration has been developed. The present work aimed to formulate Cassia tora extract (CTE) phytosomal gel that could be used for its antifungal effects and improved therapeutic activity. The CTE phytosomes were formulated by varying the concentration of lecithin (0.15-0.25% w/v) and speed of rotation (100-160 rpm). A 22 factorial design was applied by taking the above two parameters as independent variables and vesicular size and entrapment efficiency as dependent variables. The phytosomes were also evaluated for polydispersity index, zeta potential and in vitro drug release. The optimized phytosomes of CTE were further developed into a gel, the optimized gel was also evaluated, and the stability studies were conducted. The optimized CTE phytosome showed a vesicular size of ~ 124 nm and entrapment efficiency of 95%. The CTE phytosomes showed a drug release of 58.79% in 24 hours following the Higuchi order of release. The CTE phytosomes were formulated into a gel by using 1% Carbopol 934 and were evaluated for pH, viscosity and homogeneity. The formulated gel showed better penetration than conventional gel, and stability changes indicated no major changes to the CTE phytosomal gel. The optimized gel had better penetration and drug release than the conventional gel. Its therapeutic activity, therefore, can be enhanced.