The development and evaluation of the sunscreen product for UV-Visible protection

Abstract

This study aimed to develop and evaluate the sunscreens protected against UV and visible light radiation. The development of sunscreens was started from the survey of the frequently used UV filters in the commercial products. The UV filter which showed high frequency of usage were selected for screening of UV and visible light protective ability. The selected inorganic UV filters/pigments were studied the effect of particle size and surface coating on UV and visible light protection. The filters having the maximum efficacy in UV and visible light protection were selected to incorporate in the sunscreen formulations. The colored sunscreens were developed and evaluated their efficacy based on the measurement of the UV and blue/visible light transmission through sunscreen film applied on a substrate. The indicated parameters were sun protection factor (SPF; UVB protection), UVA protection factor (UVAPF; UVA protection), and porphyrin protection factor (PPF; Blue light protection). The formulated sunscreens were again investigated the UV protective efficiency by internationally recognized methods. The selected UV and Vis filters were studied the effect on blue light protection in different types of base formulation. Finally, the developed color sunscreen was proved the blue light protection ability by the comparison with the commercial sunscreen products claimed to protect blue light radiation. From the survey, the selected UV filters were included in the study such as Butyl methoxydibenzoylmethane (BMDM), Ethylhexyl methoxycinnamate (EHMC), Bis-ethylhexyloxyphenol methoxy-phenyl Triazine (BEMT), Octocrylene (OCR), Ethylhexyl salicylate (EHS), Homosalate (HMS), Diethylamino hydroxybenzoyl hexyl benzoate (DHHB), Ethylhexyl triazone (EHT), Methylene bis-benzotriazolyl tetramethyl-butylphenol (MBBT). The new generation UV filters such Tris-biphenyl triazine (TBPT), and Bis-ethylhexyloxy-phenol methoxyphenyl triazine (and) polymethyl methacrylate (BENT AQ) were also included. Among these filters, only TBPT could provide the absorptive efficiency covering from UV to visible light wavelength. The inorganic UV filters/pigments included in the study were titanium dioxide (TiO2) and zinc oxide (ZnO). The effect of their particle size and surface coating on UV and visible light protection showed that, nanosize TiO2 provided better UV protection than submicronsize TiO2. Less significant different in UV protection was found between surface coated and uncoated nanosize TiO2. The uncoated submicronsize TiO2 showed the best protection in the blue/visible light wavelength, followed by coated submicronsize TiO2 and nanosized TiO2. The iron oxides having submicronsize showed better protection in both UV and visible light wavelengths, compared with those having micronsize. The addition of blended iron oxides to TiO2 can enhance the protection against UV and visible light compared to TiO2 alone. However, this was in the case only for uncoated and coated nanosized, coated submicronsize, not for uncoated submicronsize TiO2. The combination of colored sunscreen with TBPT can improve both UVB, UVA and blue light protection in term of SPF, UVAPF, and PPF values respectively. In addition, the base formulations were greatly affected the protective ability against blue light radiation. The developed color sunscreen provided the SPF more than 50, UVAPF followed the requirement of European regulation, and PPF more than the commercial sunscreen products available on the market in protecting the blue light radiation. These studies were clear that different physicochemical properties of UV and Vis filters play a crucial role in their ability to protect against UV and blue/visible light radiation.

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