Navegando por Palavras-chave "Sun protection factor"

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    Desenvolvimento de nanopartículas lipídicas sólidas contendo filtro solar orgânico e óleo vegetal da flora brasileira
    (Universidade Federal de São Paulo, 2017-06-23) Bim, Antonio Vinicius Kosiski [UNIFESP]; Silva, Vânia Rodrigues Leite e [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    The use of sunscreen products is widely promoted by schools, government agencies and health-related organizations to minimize sunburn and skin damage, which can lead to skin cancer. In this study, we developed stable solid lipid nanoparticles (SLN) containing the UV chemical filter octyl methoxycinnamate (OMC), associated or not with wheat germ oils (Triticum sativum Lank) and urucum oil (Bixa orellana L.) using emulsification techniques, high shear dispersion and high pressure homogenization. It was possible to obtain nanoparticles with adequate dimensions and stability for application in sunscreen formulations. Ex vivo tests (skin diffusion) did not show significant permeation, whereas in vitro tests (PAMPA) demonstrated that SLNs are able to diffuse through the lipid layer without altering its size, suggesting stability in the skin. In vitro solar protection factor (SPF) studies indicate that when 20% of the OMC was replaced by urucum oil, there was no reduction in SPF, suggesting that a decrease in the amount of chemical filter may be a viable alternative to an effective sunscreen, in combination with oils as urucum, rich in antioxidants. The results corroborate a strong trend to increase the safety of sun protection products by reducing the use of ultraviolate (UV) chemical filters producing formulations with lower concentrations of OMC while maintaining SPF. Further investigations of in vivo SPF are required to evaluate the suitability of these formulations for human use.
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    Green Coffea arabica L. seed oil influences the stability and protective effects of topical formulations
    (Elsevier B.V., 2015-01-01) Wagemaker, Tais A. L.; Silva, Silas A. M. [UNIFESP]; Leonardi, Gislaine R. [UNIFESP]; Maia Campos, Patricia M. B. G.; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)
    Green Coffea arabica L. seed oil (GCO) has been used as an active ingredient in many skin care products, due to its properties as an emollient, improver of skin hydration and absorbent of UVB radiation. However, to obtain a stable, effective and pleasant formulation containing variable amounts of GCO it is necessary to know specific chemical characteristics of the combined ingredients. Thus, this study evaluated rheological behavior, presence of liquid crystals (LCs) and skin protective effects of GCO-containing formulations aiming to correlate these parameters with GCO concentrations by using a principal component analysis (PCA). Formulations containing GCO or not (0-15%) were submitted to physical stability assays by determinations of rheological behavior after 90 days storage, detection of LCs by polarized light microscopy and in vitro determination of the sun protection factor (SPF). in vivo protective effects in mice were evaluated with biophysical techniques and histological analysis. Data were correlated using PCA. Despite the low SPF values, GCO addition to formulations resulted in significant and proportional increases of these values. It is concluded that formulation stability and skin protective properties are influenced by GCO but desirable effects are only possible when GCO is present in high concentrations. (C) 2014 Elsevier B.V. All rights reserved.