Planejamento e síntese de derivados de benzofenonas: estudos de fotoproteção e fotodegradação in vitro

• Autor(a) principal: Yamasaki, Paulo Renato [UNESP]
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/150855
• topic: Fotoproteção; Antioxidante; Filtros solares; Radiação UV; Câncer de pele; Fotoenvelhecimento

Erythema, inflammation, photoaging and skin cancer are the most common problems caused by UV radiation. Stratified into 3 regions of the light spectrum: UVA (320-400 nm), UVB (280-320 nm) and UVC (200-280 nm ). The UVA and UVB radiations are the most harmful to the skin, because the UVC radiation is retained by the ozone layer and is only used as a germicide artificially. The incidence of UVA radiation on the skin induces the formation of ROS (reactive oxygen species) that affects indirectly the human DNA and can induce skin cancer. UVB radiation directly affects the pyrimidine bases of DNA molecules making it difficult to repair, increasing the chances of the individual developing skin cancer. To minimize and prevent damage caused by UV radiation to the skin sunscreens have been developed. Divided into organic and inorganic, presenting ability to block (inorganic) or absorbing (organic) incident UV radiation on the skin. Among the organic filters are benzophenones and cinnamates. To assist in the photoprotective effect of the filters, the combination with antioxidant molecules have been recommended. The objective of this study was to plan and develop new hybrid compounds of benzophenone with cinnamic acids with antioxidant incremental properties, analyzing photodegradation using imaging mass spectrometry techinques, and checking the effects of molecular change in absorptivity in the UV spectrum of the compounds. The new hybrids were evaluated for potential photoprotection, photodegradation and antioxidant capacity, with promising results, therefore, kept the photoprotective capacity as well, antioxidant activity, in addition to having relative stability against UV radiation and absorptivity increase in UVA region.