Development of novel topical formulation from fullerene with antibacterial activity against Propionibacterium acnes

Abstract

Acne vulgaris is a chronic skin disease of the pilosebaceous unit. Several pathophysiological associations have been identified in which Propionibacterium acnes plays a major role. Although there are a number of antibiotic therapies suggested for acne, many of them have limitations in their safety and efficacy. Therefore, there is a high demand to develop a safe alternative therapy for acne. Fullerene is an emerging nanomaterial believed to be a potential candidate for the treatment of acne due to its antibacterial and antioxidant activities. The low water solubility of fullerene limits its application in the cosmeceutical products. In the present study, a water soluble derivative of fullerene, glycine-fullerene conjugate (Gly-Ful), was developed and optimized using Design expert® software. As the positively charged molecules could act directly on the negatively charged bacterial cellular membranes, chitosan surface modified glycine-fullerene conjugate nanoparticles (Chi-Gly-Ful NPs) were prepared and Chi-Gly-Ful NPs gel was formulated for topical use in acne treatment. In vitro susceptibility of Propionibacterium acnes to Chi-Gly-Ful NPs formulation and comparator drug (streptomycin) was evaluated. The results showed that Chi-Gly-Ful NPs formulation inhibited effectively the growth of P. acnes and showed comparable antibacterial activity to streptomycin. The minimum bactericidal concentration (MIC) for Chi-Gly-Ful NPs was 8 µg/ml. Chi-Gly-Ful NPs at the concentrations of 25–400 µM showed no cytotoxicity on L929 fibroblast cells. Conclusively, our present work showed for the first time that Chi-Gly-Ful NPs has antimicrobial effects against P. acnes with no cytotoxic effect, suggesting Chi-Gly-Ful NPs as a promising novel therapeutic agent for the treatment of acne. © 2020 Taylor & Francis Group, LLC.