In this thesis, a series of in vitro diffusion studies were performed to evaluate the transmembrane permeation of picaridin and oxybenzone across human epidermis and poly(dimethylsiloxane) (PDMS) membrane. Transdermal permeation of picaridin and oxybenzone from four commercially available repellent and sunscreen products was also investigated by using different application concentrations and sequences. The results obtained were then compared to those of the repellent DEET and the sunscreen oxybenzone under identical experimental conditions. Permeation of picaridin and oxybenzone across human epidermis was suppressed when both compounds were used concurrently. Increasing concentration of the test compounds further reduced the permeation percentage of picaridin and oxybenzone. While permeation characteristics were correlative between human epidermis and artificial PDMS membrane, permeability of PDMS membrane was significantly larger than that of human epidermis. This finding was different from concurrent use of DEET and oxybenzone in which a synergistic permeation enhancement was observed between the two substances. Transdermal permeation of picaridin across human epidermis from various commercially available spray preparations was significantly lower than that of DEET from similar spray products, both alone and in combination with sunscreen oxybenzone. Concurrent application of the commercial products resulted in either no change or suppression of permeation of picaridin and oxybenzone. This finding was also different from concurrent application of DEET and oxybenzone using commercial preparations. In addition, permeation of picaridin and oxybenzone across human epidermis was dependent on application concentration, use sequence, and preparation type.It was concluded from this thesis that picaridin would be a better candidate for concurrent application with sunscreen preparations in terms of percutaneous permeation.

In this thesis, a series of in vitro diffusion studies were performed to evaluate the transmembrane permeation of picaridin and oxybenzone across human epidermis and poly(dimethylsiloxane) (PDMS) membrane. Transdermal permeation of picaridin and oxybenzone from four commercially available repellent and sunscreen products was also investigated by using different application concentrations and sequences. The results obtained were then compared to those of the repellent DEET and the sunscreen oxybenzone under identical experimental conditions. Permeation of picaridin and oxybenzone across human epidermis was suppressed when both compounds were used concurrently. Increasing concentration of the test compounds further reduced the permeation percentage of picaridin and oxybenzone. While permeation characteristics were correlative between human epidermis and artificial PDMS membrane, permeability of PDMS membrane was significantly larger than that of human epidermis. This finding was different from concurrent use of DEET and oxybenzone in which a synergistic permeation enhancement was observed between the two substances. Transdermal permeation of picaridin across human epidermis from various commercially available spray preparations was significantly lower than that of DEET from similar spray products, both alone and in combination with sunscreen oxybenzone. Concurrent application of the commercial products resulted in either no change or suppression of permeation of picaridin and oxybenzone. This finding was also different from concurrent application of DEET and oxybenzone using commercial preparations. In addition, permeation of picaridin and oxybenzone across human epidermis was dependent on application concentration, use sequence, and preparation type.It was concluded from this thesis that picaridin would be a better candidate for concurrent application with sunscreen preparations in terms of percutaneous permeation.

Orientador: Marian Rosaly Davolos / Banca: Sergio Antonio Marques de Lima / Banca: Kassandra Azevedo Tadini / Resumo: A preocupação com a radiação ultra-violeta (UV) do espectro eletromagnético que atinge a superfície terrestre, devido ao aumento do índice de câncer de pele, tem incentivado a pesquisa de produtos para a proteção da pele. Este trabalho tem como objetivo a obtenção e estudo do filtro inorgânico ZnO:Ti4+ com 1, 5, 10, 20, 40, 50% em mol do dopante e a associação dos filtros dopados obtidos com o filtro orgânico 1-(4-terc-butilfenil)-3-(4- metoxifenil)propano-1,3-diona ou butil metoxi dibenzoil metano (bmdm), comercialmente denominado Eusolex 9020. Os filtros dopados foram obtidos pelo método sol-gel, com razão de hidrólise de 0,1 e de 0,01. As amostras foram caracterizadas por espectroscopia de absorção através de medidas de refletância difusa (RD), espectroscopia na região do infravermelho (IV), espectroscopia na região do ultravioleta - visível (UV-Vís), difratometria de raios X (DRX), colorimetria, medidas de potencial zeta, razão UVA/UVB e comprimento de onda crítico foram calculados para conhecer o desempenho dos filtros na região do UVA. Os resultados de DRX indicam a formação da fase ZnO wurtzita para dopagens de até 10%. Acima dessa porcentagem de "dopante", observa-se a formação de fases de titanatos de zinco (Zn2TiO4 e ZnTiO3). Os espectros no IV apresentam bandas referentes à ligação metaloxigênio deslocadas para maiores números de onda com o aumento da quantidade de dopante, devido ao efeito da força de ligação e do tamanho do íon de titânio em relação ao de zinco nas interações metal-oxigênio. Os espectros de RD apresentam deslocamento das bandas para a região do visível. Os filtros dopados obtidos foram, então, associados com o filtro orgânico bmdm. Os filtros associados foram caracterizados pelas mesmas técnicas acima descritas. Nos espectros IV dos filtros... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The concern with UV radiation of the electromagnetic spectrum that reaches the earth's surface has encouraged the research of products for skin protection due to increased rates of skin cancer. This study aims to obtain and study the inorganic filter ZnO:Ti4+ with 1, 5, 10, 20, 40, 50 at% of doping and the association with doped filters developed through organic filter 1 - (4-tert- butyl phenyl) -3 - (4-methoxyphenyl) propane-1 ,3-dione or butyl methoxy dibenzoyl methane (bmdm), trade name Eusolex 9020®. Doped filters were obtained by the sol-gel method, with hydrolysis ratio of 0.1 and 0.01. The samples were characterized by absorption spectroscopy using diffuse reflectance (DR), infrared (IR) spectroscopy, ultraviolet - visible (UV-Vis), X-ray diffraction (XRD), colorimetric and zeta potential measurements. UVA/UVB ratio and critical wavelength were calculated to know the filter's performance in the UVA region. XRD results indicate the ZnO wurtzite phase formation step for doping levels up to 10%. Above this percentage of doping, phases of zinc titanates (Zn2TiO4 and ZnTiO3) we observed. The IR spectra show bands of the metal-oxygen shifted to higher wave numbers and an increasing amount of dopant due to the bond strength and size effects of the titanium ion compared to zinc ion in metaloxygen interactions. The RD spectra show shifts of bands for the visible region. Doped filters were then associated with the bmdm organic filter. The associated filters were characterized by the same techniques just described above. In the IR spectra of the associated filters, there is also the band on the metal-oxygen, splitting and shifting of the band related to the carbonyl group when compared with the free bmdm, that indicates an association between the filters. The absorption bands of doped filters do not cover... (Complete abstract click electronic access below) / Mestre

Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-03-08T18:16:41Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Katyane 2.pdf: 4899390 bytes, checksum: 591b77920f0440069d4c7a3d4ec83b37 (MD5) / Made available in DSpace on 2017-03-08T18:16:41Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Katyane 2.pdf: 4899390 bytes, checksum: 591b77920f0440069d4c7a3d4ec83b37 (MD5) Previous issue date: 2013-02-26 / Facepe e Capes / A radiação UV compreende uma região do espectro eletromagnético e é classificada conforme o comprimento de onda em: UVC (100-290 nm), UVB (290-320 nm) e UVA, UVA2 (320-340 nm) e UVA1 (340-400nm). Apesar de serem responsáveis pela maioria dos efeitos benéficos, também o são pelos efeitos prejudiciais e, mesmo tendo o organismo humano desenvolvido mecanismos de defesa, estes não são suficientes, por isso o uso de preparações fotoprotetoras tornou-se essencial. A associação de filtros solares, apesar de ser uma forma usual para aumentar os valores do fator de proteção solar (FPS) destas preparações, ocasiona uma série de problemas, como irritação, reações fototóxicas e alérgicas. Em vista disso, o objetivo desse estudo foi o uso de bentonitas como filtro físico para associação a filtros químicos UVA - avobenzona (AVO), UVB - metoxicinamato de etilexila (EHMC) ou de amplo espectro - oxibenzona (OXI). A escolha da bentonita justifica-se, além de ser um recurso natural, por sua estrutura lamelar, podendo gerar compostos de intercalação, o que pode proteger o filtro químico do sol, prolongando sua ação, e a pele do filtro solar. Foram produzidos, então, via solução, sistemas de cada filtro químico supracitado com bentonita sodica (SB) ou organofílica (OB), em diferentes proporções, obtidos por centrifugação [C] ou evaporação rotativa [R]. O rendimento dos produtos foi calculado indiretamente por espectrofotometria do sobrenadante dos centrifugados, de forma que foram escolhidas as proporções de maior rendimento de cada sistema, [C] e [R], para serem caracterizados. Os melhores sistemas com os respectivos rendimentos foram os seguintes: AVO-SB 3:1 (63 ± 1%); AVO-OB 2:1 (51 ± 1%); EHMC-SB 0,5:1 (79 ± 1%); EHMC-OB 0,5:1 (82 ± 1%); OXI-SB 1:1 (59 ± 2%); OXI-OB 1:1 (58 ± 1%). Os produtos foram caracterizados por difração de raios X (DRX), análise termogravimétrica (TG), calorimetria exploratória diferencial (DSC), espectroscopia de infravermelho com transformada de Fourier (FTIR) e microscopia eletrônica de transmissão (MET), os quais, de forma geral, confirmaram a formação dos compostos de intercalação. Para análise dos valores de FPS in vitro, todos os filtros foram incorporados em uma emulsão-base a 2,5%, em sua forma pura ou intercalada em bentonita. As preparações mostraram-se estáveis pelo teste de estabilidade preliminar e com valores de pH em conformidade com a via tópica. Os dados de transmitância revelaram um aumento significativo do FPS em todos os compostos de intercalação de AVO, se comparado ao filtro puro (0,7 ± 0,5), destacando-se o sistema AVO-OB [C] (17 ± 2); com o EHMC, mais uma vez o sistema com OB [C] se destacou (17 ± 1 versus 8 ± 1 para o EHMC puro), tendo sido o único, nesse caso, a ter um aumento significativo; os resultados dos compostos de intercalação contendo OXI não mostraram diferença nos valores de FPS, provavelmente porque o FPS da OXI pura já é bem alto (19 ± 3), pelo contrário, o sistema OXI-SB [C] reduziu o FPS (12 ± 0,5). Os resultados mostraram a viabilidade da formação de compostos de intercalação filtros solares – bentonita e da utilização, em especial, da OB em formulações fotoprotetoras. / UV radiation comprises a region of the electromagnetic spectrum and is classified as wavelength: UVC (100-290 nm), UVB (290-320 nm) and UVA UVA2 (320-340 nm) and UVA1 (340-400 nm). Despite being responsible for the most beneficial effects, so are the harmful effects and even having the human organism developed defense mechanisms, these are not enough, so the use of sunscreen preparations became essential. The combination of sunscreens, despite being a usual way to increase the values of the sun protection factor (SPF) of these preparations, causes a number of problems, such as irritation, allergic and phototoxic reactions. In view of this, the objective of this study was the use of bentonite as a physical filter for joining chemical filters UVA - avobenzone (AVO), UVB - methoxycinnamate etilexila (EHMC) or broad-spectrum - oxybenzone (OXI). The choice of bentonite is justified, besides being a natural resource for its lamellar structure, which can generate intercalation compounds, which can protect the chemical filter the sun, prolonging its action, and the skin of sunscreen. Produced were then via solution, each filter chemical systems above with sodium bentonite (SB) or organophilic (OB), in different proportions, obtained by centrifugation [C] or rotary evaporation [R]. The yield of the products was calculated indirectly by spectrophotometry of the supernatant centrifuged, were chosen so that the proportions of each system higher yield, [C] and [R], to be characterized. The best systems with their yields were as follows: AVO-SB 3:1 (63 ± 1%); AVO-OB 2:1 (51 ±2%); EHMCSB 0.5:1 (79 ± 1%); EHMC-OB 0.5:1 (82 ± 1%); OXI-SB 1:1 (59 ± 2%); OXI-OB 1:1 (58± 1%). The products were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), differential scanning calorimetry (DSC), infrared spectroscopy Fourier transform (FTIR) and transmission electron microscopy (TEM), which so Generally, confirmed the formation of intercalation compounds. For analysis of in vitro SPF values, all filters were incorporated into an emulsion base 2.5% in pure form or interleaved bentonite. The preparations were stable for preliminary stability test with pH values in accordance with topically. The transmittance data revealed a significant increase in FPS in all intercalation compounds of AVO, compared to pure filter (0.7 ± 0.5), highlighting the AVO-OB system [C] (17 ± 2); with EHMC, again with the system B [C] is highlighted (17 ± 1 versus 8 ± 1 for pure EHMC), being the only, in which case , to have a significant increase, the results of intercalation compounds containing OXI showed no difference in SPF values, probably because the SPF of pure OXI is already quite high (19 ± 3), in contrast, the system OXY -SB [C] reduced the FPS (12 ± 0.5). The results show the feasibility of the formation of intercalation compounds sunscreens - bentonite and use, especially in formulations of OB sunscreens.

The growing popularity of physical sunscreens will also lead to an increased release of the ingredients from zinc oxide (ZnO) sunscreens into marine environments. Though zinc (Zn) is a necessary micronutrient in the ocean, greater than natural Zn concentrations are being released into marine environments by use of sunscreens. The extent of the consequences of the addition of Zn to the ocean are not fully understood. We investigated effects of materials released by zinc oxide (ZnO) sunscreens on the development of California purple sea urchin, Strongylocentrotus purpuratus. Embryos developed in various concentrations of Zn, the sources of which included zinc-containing compounds: ZnO and ZnSO4; and ZnO sunscreens: All Good, Badger, and Raw Elements. ZnO sunscreens were slightly more toxic than ZnO and ZnSO4, suggesting that the sunscreens may release additional unknown materials that are detrimental to sea urchin embryo development. All concentrations of Zn exposure resulted in significant malformations (skeletal abnormality, stage arrest, axis determination disruption), which were identified using light and fluorescent confocal microscopy. Developing embryos internalize Zn2+in proportion to the concentration of Zn in their environment. Additionally, both ZnO sunscreens and ZnO and ZnSO4at 1ppm Zn, significantly increased calcein-AM (CAM) accumulation, indicating decreased multidrug resistant (MDR) transporter activity. This is the first research that we know of to show that ZnO sunscreens release high concentrations of Zn that are internalized by and have detrimental effects on aquatic organisms.

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Master of Science / Department of Chemical Engineering / Larry E. Erickson / The damage that can be inflicted by ultraviolet radiation has gained widespread interest. Traditionally sunscreens are made of organic and inorganic components that block two of the three types of ultraviolet radiation, UVA and UVB. This report is a literature review of several articles that have investigated the effects of inorganic UV filters; specifically titanium dioxide and cerium dioxide. There are concerns about absorption of titanium dioxide into the skin and the adverse reactions that could occur, but it was found that there is little to no absorption. Similarly the photostability of titanium dioxide is a concern; this was found to be remedied in part by a surface treatment to the titanium dioxide. The combination of titanium dioxide and carnauba wax was also studied and found to enhance the properties of both the organic and inorganic filters. Ceria was studied as a possible replacement for titanium dioxide. It was found to have similar ultraviolet shielding properties while minimizing the photocatalytic activity and photocytotoxicity seen in titanium dioxide.

Background. Skin cancer is the most common form of cancer in the United States. The main modifiable risk factor for skin cancer is exposure to excessive sun and UV radiation. More than 90% of all skin cancers are known to be caused by sun exposure. However, studies on excessive sun and UV exposure are limited. The purpose of this study was to examine risk and protective factors affecting sun protection behaviors of adult women in the United States. Methods. Data on U.S. adult women (n=17,425) from the 2003 National Health Information Survey (NHIS) was analyzed. Sun protection behaviors were assessed using three variables: use of sunscreen, staying in the shade, and wearing protective clothing when outside for an hour or more on a very sunny day. Demographic characteristics, risk and preventive factors such as visit to the general doctor, visit to the dentist, most recent mammogram, most recent pap smear, vigorous exercise, cigarette use, and alcohol use were examined using multiple logistic regression. Results. Only 45% of the respondents indicated that they consistently use sunscreen or stay in the shade when outside on a very sunny day for an hour or more and 15.8% of the respondents reported that they consistently wore protective clothing. The adjusted logistic regression analyses indicated that race, age, education, income, geographic region, employment status, exercise, history of cancer, tobacco use, and alcohol use were statistically significant predictors for participation in the sun protection behaviors. Conclusions. A majority of the U.S. adult female population do not use protection from excessive sun. Education programs for sun protection behaviors should target young, low income women with less than high school education who participate in other health risk behaviors, such as tobacco and alcohol use. Furthermore, sun protection education should be incorporated with other health education messages that target at risk populations.