Hesperetin loaded proposomal gel for topical antioxidant activity

The present study was aimed at formulating and evaluating hesperetin-loaded proposomal gel for topical antioxidant activity. Hesperetin-loaded proposomes were first formulated and optimized with the central composite design and were characterized for particle size, polydispersity index, zeta potential and entrapment efficiency. In vitro release studies were also performed for the formulation. Various polymeric gel bases were assessed and one of them was selected to formulate the proposomal gel. The gels were characterized for their appearance, content uniformity, viscosity, spreadability and swelling index. In vitro diffusion studies were also carried out on the proposomal gel. Finally, in vitro antioxidant potentials of hesperetin and the proposomal formulation was determined using the 2,2- diphenyl-1-picrylhydrazyl hydrate (DPPH) assay. The optimized proposomal formulation showed enhanced in vitro drug release with a release of 95.51 ± 8.85% after 84 h compared to the hesperetin dispersion which released only 34.00 ± 1.71%. 1% carbopol was selected as a suitable gel base for the proposomal gel. The proposomal gel formulated showed good properties and was able to further sustain the drug release from the proposomes by releasing 42.63 ± 2.11% of the drug after 144 h. Finally, hesperetin and hesperetin-loaded proposomes showed comparable in vitro antioxidant activities with IC₅₀ values of 82.15 μg/mL and 88.07 μg/mL, respectively. We can conclude that hesperetin-loaded proposomal gel can be an effective formulation with a controlled release profile and could be used to treat topical oxidative conditions.