Formulation and optimization of clotrimazole-loaded proniosomal gel using 3(2) factorial design

The main aim of the study was to develop and statistically optimize the proniosomal gel for enhanced transdermal delivery using 3(2) factorial designs to investigate the influence of both non-ionic surfactant and cholesterol to maximize the entrapment efficiency and flux. The concentration of non-ionic surfactant and cholesterol were taken as independent variables, while entrapment efficiency and flux were taken as dependent variables. The study showed that the entrapment efficiency depends on both cholesterol and surfactant, whereas permeation flux depends only on the surfactant. Proniosomal gel showed a significantly enhanced drug permeation through the skin, with an enhancement ratio 3.81±1.85 when compared to the drug solution. Comparative evaluation of permeation studies and the in vitro release study of optimized proniosomal gel (F5) with that of marketed gel and carbopol gel showed that the penetration of the optimized formulation was enhanced 1.75 times in comparison with that of the marketed formulation, and the release was in a controlled manner. Similarly, the anticandidial activity showed a significantly higher activity (p<0.05) than the marketed and carbopol gel. This may be due to the enhanced penetration of noisome-containing drug through the fungal cell wall, inhibiting the ergo sterol synthesis, thereby causing the fungal cell death due to the presence of penetration enhancer. The stability study at two different temperatures (30 ± 2°C and 4 ± 2°C) confirmed that the formulations were stable even at the end of 45 days. Hence, proniosomal gel is an efficient carrier for the delivery of clotrimazole, thereby prolonging the action.