Design and Evaluation of Topical Gel Formulation of Fonio Starch Nanoparticles

ABSTRACT Topical gel formulations of fluconazole‐loaded fonio starch nanoparticles (SNPs) were designed and evaluated. Fonio (native and acid‐modified) SNPs were produced by nanoprecipitation. Fonio SNPs were characterized for size, polydispersity index, solubility, water absorption capacity, FTIR spectra, XRD patterns, drug entrapment, and in vitro drug release. The fonio SNPs were incorporated into gels, using carboxymethylcellulose as the gelling agent. The gels were evaluated for pH, viscosity, spread, drug release, and antifungal activity. The SNPs’ sizes ranged from 46.03 to 104.00 nm with a Polydispersity Index of 0.136–0.266 for both native and acid‐modified. Acid‐modified Fonio SNPs showed higher solubility but decreased water absorption capacity, drug entrapment, and drug release properties. FTIR fingerprints were characteristic of granular starches, while x‐ray patterns shifted from the typical A‐type starches. The SNPs generally released 75% of fluconazole within 30 min. The gels exhibited a pH range of 9.67–10.03, shear‐thinning behavior, with a spread of 3.5–7.0 cm. Fluconazole release from the gels was complete. Fluconazole‐loaded fonio SNP gels exhibited greater antifungal activity against Trichophyton rubrum than fluconazole gel and proprietary miconazole cream. Fluconazole‐loaded fonio starch nanoparticle gel may be used as a topical treatment based on its improved topical drug delivery and antimycotic activity.