Formulation, Optimization, and Characterization, of Allicin-Loaded Β-Cyclodextrin Nanosponges Incorporated into a Topical Gel

Abstract

Background: Fungal infections remain a significant therapeutic challenge due to recurrence, limited treatment options, and reduced susceptibility to conventional antifungal agents. Allicin, a natural organosulfur compound, possesses promising antifungal activity but requires an appropriate delivery system for effective localized application. The present study aimed to develop an allicin-loaded nanosponge incorporated into a topical gel. Method: Allicin-loaded nanosponges were prepared by the emulsion solvent diffusion technique using ethyl cellulose, polyvinyl alcohol (PVA), and Pluronic F68. A central composite design was employed, with PVA (600–1200 mg) and ethyl cellulose (400–600 mg) as independent variables. Particle size and entrapment efficiency were selected as responses. The optimized formulation was incorporated into 1% Carbopol 940 gel and evaluated for physicochemical properties. Results: The prepared nanosponges showed particle sizes of 201.61–361.27 nm, zeta potentials of −11.5 to −19.3 mV, and entrapment efficiencies of 58.9–82.4%. PF7 was optimized with an entrapment efficiency of 82.4% and particle size of 273.52 ± 3.28 nm. It exhibited progressive drug release, reaching 95.57% at 12 h. The nanosponge-loaded gel was greenish-brown, clear, and thick, with pH 6.7 ± 0.09, spreadability 12.2 ± 0.78 g·cm/s, and viscosity 4425 ± 33.64 cps. Discussion: The nanosponge system provided nanoscale particle size, satisfactory drug entrapment, and sustained allicin release. Incorporation into Carbopol 940 produced a gel with suitable topical physicochemical characteristics, potentially supporting localized and prolonged drug delivery. Conclusion: The developed allicin-loaded nanosponge gel demonstrated suitable characteristics for topical antifungal delivery and may provide a promising platform for localized allicin administration.