Chitosan-bovine serum albumin-Carbopol 940 nanogels for mupirocin dermal delivery: ex-vivo permeation and evaluation of cellular binding capacity via radiolabeling

The goal of this study was to develop and examine the nanogel-based topical delivery system of mupirocin. Nanogels were prepared with chitosan and bovine serum albumin by ionic gelation and Carbopol 940 was added to improve the gelling/adhesive properties. Detailed characterization studies were performed and the cellular binding capacity of radiolabeled nanogels was investigated on CCD-1070Sk cell lines. Results indicate the successful formation of nanogels with particle size and zeta potential ranged between 341.920-603.320 nm and 13.120-24.300 mV, respectively. The mechanical and rheological studies proved pseudoplastic and strong elastic gel behavior (G' > G''). Mupirocin was successfully entrapped into nanogels with a ratio of more than 95% and the loaded drug was slowly released up to 93.89 ± 3.07% within 24 h. The ex vivo penetration and permeation percentages of mupirocin were very low (1.172 ± 0.202% and 0.161 ± 0.136%) indicating the suitability of nanogels for dermal use against superficial skin infections. The microbiological studies pointed out the effectiveness of nanogels against Staphylococcus aureus strains. Nanogels did not show toxicity signs and the cell binding capacity of radiolabeled formulations was found to be higher than [^99mTc]NaTcO₄ to CCD-1070Sk cell line. Overall, mupirocin nanogels might be considered as a potential and safe topical treatment option for bacterial skin infections.