Preparation and Evaluation of a Microsponge Dermal Stratum Corneum Retention Drug Delivery System for Griseofulvin

Griseofulvin (GF) is used as an antifungal to treat superficial skin fungal infections such as tinea capitis and tinea pedis. Currently, GF is only available in traditional oral dosage forms and suffers from poor and highly variable bioavailability, hepatotoxicity, and long duration of treatment. Therefore, the main objective of this study was to reduce the side effects of the drug and to increase the concentration of the drug retained in the cutaneous stratum corneum (SC) and improve its efficacy through the preparation of drug-laden GF microsponge (GFMS). The emulsification-solvent-diffusion method was used to prepare GFMS, and the prescriptions were screened by a single-factor approach. The optimized formulation (GFF8) had a microsponge particle size (μm) of 28.36 ± 0.26, an encapsulation efficiency (%) of 87.53 ± 1.07, a yield (%) of 86.58 ± 0.42, and drug release (%) from 77.57 ± 3.88. The optimized microsponge formulation was then loaded into a Carbopol 934 gel matrix and skin retention differences between the microsponge gel formulation and normal gels were examined by performing skin retention and fluorescence microscopy tests. Finally, the hepatoprotective and cutaneous stratum corneum retention abilities of microsponge gel formulations compared to oral GF formulations were assessed by hepatotoxicity, pharmacokinetics, and tissue distribution studies. This provides a new perspective on GF dermal stratum corneum retention administration.