Niosomes gel of apigenin to improve the topical delivery: development, optimization, ex vivo permeation, antioxidant study, and in vivo evaluation.

Niosomes (NS) are the promising and novel carrier of the drug for effective transdermal delivery. Apigenin (AN) is a natural bioactive compound and has various pharmacological activities. AN is poorly water soluble which directly affects therapeutic efficacy. The aim of this research work was to develop the AN-NS gel to improve transdermal delivery. The thin-film hydration method was used for the development of AN-NS. The optimized AN-NS (AN-NS2) has a vesicle size of 272.56 ± 12.49 nm, PDI is 0.249, zeta potential is -38.7 mV, and entrapment efficiency of 86.19 ± 1.51%. The FTIR spectra of the AN-NS2 depicted that AN encapsulated in the NS matrix. AN-NS2 formulation was successfully incorporated into chitosan gel and evaluated. The optimized AN-NS2 gel (AN-NS2G4) has 2110 ± 14cps of viscosity, 10.40 ± 0.21g.cm/sec of spreadability, and 99.65 ± 0.53% of drug content. AN-NS2G4 displayed significantly (p < 0.05) higher AN released (67.64 ± 3.03%) than pure AN-gel (37.31 ± 2.87%). AN-NS2G4 showed the Korsmeyer Peppas release model. AN-NS2G4 displayed significantly (p < 0.05) higher antioxidant activity (90.72%) than pure AN (64.53%) at 300 µg/ml. AN-NS2G4 displayed significantly (p < 0.05) higher % inhibition of swelling than pane AN-gel in carrageenin-induced paw oedema in rats. The finding concluded that niosomes-laden gel is a good carrier of drugs to improve transdermal delivery and therapeutic efficacy.