Formulation and Evaluation of Diosmin-Loaded Niosomal Gel for Anti-Inflammatory Activity
Objective: The present study aimed to formulate and evaluate a diosmin-loaded niosomal gel for enhanced topical anti-inflammatory activity. Methods: Diosmin, a natural flavonoid with poor solubility and limited bioavailability, was encapsulated into non-ionic surfactant-based niosomes using the thin-film hydration method. Various formulations (DF1–DF10) were developed by varying the concentrations of Span 60 and cholesterol to optimise vesicle characteristics (Entrapment efficiency, particle size, in vitro drug release, zeta potential). Results: The optimised formulation (DF10) exhibited an entrapment efficiency of 86.85±0.06%, a particle size of 292.5±0.7 nm, a polydispersity index (PDI) of 0.403±0.23, and a zeta potential of –24.7 mV±0.13, indicating stable, uniform vesicles. SEM analysis confirmed spherical morphology with smooth surfaces. In vitro release studies showed sustained drug release of 96.34±0.15% over 24 h. The optimized niosomal dispersion was incorporated into a Carbopol 934 gel base, neutralised with triethanolamine to form a clear, stable niosomal gel. The prepared gel exhibited desirable physicochemical properties, including a pH of 6.3±1.04, viscosity of 36,000±1.04 cP, spread ability of 20.4 g·cm/sec, and drug content of 98.5±1.02%. In vitro diffusion studies demonstrated controlled, prolonged release (95.34±0.15 % at 24 h), following zero-order kinetics with a non-Fickian mechanism, suggesting a combination of diffusion and polymer relaxation. Conclusion: The developed diosmin-loaded niosomal gel showed potential for sustained drug delivery, improved skin permeation, and enhanced therapeutic efficacy for topical anti-inflammatory treatment.