RESUMO
Long term exposure of skin to UV rays produces detrimental effects such as premature skin-ageing and skin cancer. Although, zinc oxide (ZnO) and titanium dioxide (TiO2) are good sunscreen agents, they do not provide highly efficient UV radiation protection and antioxidant and anti-aging effects. The present study was aimed at developing and characterizing ethosomes loaded with naringin and then to incorporate them into sunscreen creams containing nano-ZnO and -TiO2 to achieve adequate skin penetration and skin retention so as to scavenge the free radicals by virtue of naringin's antioxidant property. Ethosomes were prepared and optimized with respect to concentrations of ethanol and cholesterol, time of sonication, drug and lipid ratio and amount of drug. The ethosomes were evaluated for size, zeta potential (ZP), polydispersity index (PDI), encapsulation efficiency and surface morphology. Ethosomal sunscreen creams were evaluated for physicochemical tests, spreadability, antioxidant, cytotoxicity and skin permeation studies. Optimized ethosomal formulation exhibited average vesicle size, PDI, ZP and drug encapsulation efficiency of 142.5 ± 5.6 nm, 0.199 ± 0.007, -72.5 ± 2.9 mV and 33.79 ± 1.35%, respectively. Naringin ethosomes showed enhanced retention in the skin (403.44 ± 15.33 µg/cm2) compared to naringin suspension (202.81 ± 9.45 µg/cm2). The optimized sunscreen cream exhibited SPF of 21.21 ± 0.62 with negligible permeation of naringin across the skin. Ethosomes showed pronounced skin permeation for naringin and optimized cream containing naringin ethosomes along with nano- ZnO and TiO2 showed good skin retention for naringin.
Assuntos
Antioxidantes/farmacologia , Flavanonas/farmacologia , Nanopartículas/química , Pele/efeitos dos fármacos , Protetores Solares/farmacologia , Animais , Antioxidantes/química , Células Cultivadas , Flavanonas/química , Células HaCaT , Humanos , Tamanho da Partícula , Ratos , Ratos Wistar , Absorção Cutânea/efeitos dos fármacos , Protetores Solares/química , Propriedades de Superfície , ViscosidadeRESUMO
BACKGROUND: The aim of this study was to develop sunscreen creams containing polymeric nanoparticles (NPs) of naringenin for photoprotective and antioxidant effects. METHODS: Polymeric NPs of naringenin were prepared and optimized. The NPs were incorporated into sunscreen creams and evaluated for in vitro and in vivo skin retention. RESULTS: The optimized naringenin NPs showed a size of 131.2 nm, zeta potential -25.4 mV, and entrapment efficiency 32.45%. The absence of drug-excipient interaction was confirmed by Fourier transform infrared spectroscopy and differential scanning calorimetry. X-Ray diffraction analysis demonstrated the amorphization of naringenin in nanoparticles. Transmission electron microscopy showed the sphericity of the NPs with the size of <200 nm. Cytotoxicity assessment in HaCaT cells indicated non-toxic nature of naringenin NPs. In vitro skin permeation studies demonstrated that higher amount of naringenin permeated at the end of 12 hours (Q12 hours = 184.03 ± 3.37 µg/cm2 ) and deposited in the skin (10.38 ± 0.48 µg/cm2 ) from NPs as compared to plain naringenin. Sunscreen creams (SC1-SC5) containing plain naringenin or NPs with/without nano-zinc oxide and nano-titanium dioxide were prepared and evaluated. Optimized cream (SC5) containing naringenin NPs showed highest SPF value and enhanced skin retention of naringenin in comparison with NPs in suspension form and other cream formulations. CONCLUSION: Optimized nanoparticulate sunscreen cream exhibited highest skin retention and negligible skin permeation of naringenin besides showing excellent SPF value.