Optimization of hydroxypropyl methylcellulose (HPMC) and carbopol 940 in clindamycin HCl ethosomal gel as anti-acne

Clindamycin HCl has anti-acne properties because it can inhibit the growth of Propionibacterium acnes (P. acnes) bacteria. However, the bioavailability of clindamycin HCl is less than 13% of the given dose, so it needs to be developed in the form of ethosomes to increase its bioavailability. This study aimed to create a clindamycin HCl ethosomal gel preparation with varying hydroxypropyl methylcellulose (HPMC) and carbopol-940 as a gelling agent using a factorial design to obtain 4 formulas. The concentrations of HPMC and carbopol 940 used were 0.5% and 1%. The optimum formula was determined based on the pH response, viscosity, spreadability, and adhesion of the clindamycin HCl ethosomal gel preparation. Based on the factorial design analysis, HPMC and Carbopol-940 have an influence on the pH response and adhesion, while the interaction between HPMC and Carbopol-940 influences the spreadability and viscosity responses. The optimum formula was obtained with a desirability value of 0.994 at a concentration of HPMC was 1%, and Carbopol 940 was 0.5%. The minimum inhibitory concentration of the optimum clindamycin HCl ethosomal gel was 60 μg/mL. So, the clindamycin HCl ethosomal gel had a strong antibacterial activity.