Synthesis and application of a novel sunscreen-antioxidant
- 1 January 2006
- journal article
- research article
- Published by Taylor & Francis in Free Radical Research
- Vol. 40 (5) , 485-494
Abstract
Background information on the inefficacy of sunscreens to provide free radical protection in skin, despite their usefulness in preventing sunburn/erythema, prompted us to synthesize a compound which would display in the same molecule both UV-absorbing and antioxidant capacities. For this purpose, the UVB absorber, 2-ethylhexyl-4-methoxycinnamate (OMC) was combined with the piperidine nitroxide TEMPOL, which has antioxidant properties. The spectral properties of the new nitroxide-based sunscreen (MC–NO) as well as its efficacy to prevent photo-oxidative damage to lipids induced by UVA, natural sunlight and 4-tert-butyl-4-methoxydibenzoylmethane (BMDBM), a photo-unstable sunscreen which generates free radicals upon UV radiation, was studied. The results obtained demonstrate that MC–NO: (a) absorbs in the UVB region even after UVA irradiation; (b) acts as free radical scavenger as demonstrated by EPR experiments; (c) strongly reduces both UVA-, sunlight- and BMDBM-induced lipid peroxidation in liposomes, measured as reduced TBARS levels; and (d) has comparable antioxidant activity to that of commonly used vitamin E and BHT in skin care formulations. These results suggest that the use of the novel sunscreen-antioxidant or of other nitroxide-based sunscreens in formulations aimed at reducing photoinduced skin damage may be envisaged.Keywords
This publication has 54 references indexed in Scilit:
- Integrated Sun Protection Factor: A New Sun Protection Factor Based on Free Radicals Generated by UV IrradiationSkin Pharmacology and Physiology, 2004
- Sunscreens Inadequately Protect Against Ultraviolet-A-Induced Free Radicals in Skin: Implications for Skin Aging and Melanoma?Journal of Investigative Dermatology, 2003
- Photophysical and Photochemical Studies of 2-Phenylbenzimidazole and UVB Sunscreen 2-Phenylbenzimidazole-5-sulfonic Acid¶Photochemistry and Photobiology, 2002
- Ultraviolet light induced injury: Immunological and inflammatory effectsImmunology & Cell Biology, 2001
- Change of Ultraviolet Absorbance of Sunscreens by Exposure to Solar-Simulated RadiationJournal of Investigative Dermatology, 2001
- Changes in Ultraviolet Absorption of Sunscreens After Ultraviolet IrradiationJournal of Investigative Dermatology, 1999
- Photochemistry of dibenzoyl methane UVA filters Part 1Journal of Photochemistry and Photobiology B: Biology, 1995
- Photodecomposition of several compounds commonly used as sunscreen agentsJournal of Photochemistry and Photobiology A: Chemistry, 1994
- UVA-induced lipid peroxidation in cultured human fibroblastsBiochimica et Biophysica Acta (BBA) - Lipids and Lipid Metabolism, 1991
- Stereospecific synthesis of azo nitrilesThe Journal of Organic Chemistry, 1987