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Determinação de benzofenonas em matrizes ambientais por microextração adsortiva em barra seguida de análise por métodos cromatográficos
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Advisor(s)
Abstract(s)
Os contaminantes ambientais emergentes são uma ameaça para o ecossistema e a sua monitorização é crucial. O desenvolvimento científico representa um grande passo para a deteção de substâncias perigosas para o ambiente, no entanto é necessário que as técnicas apresentem uma elevada sensibilidade e que estejam de acordo com os princípios da Química Analítica Verde.
A presente dissertação consistiu no desenvolvimento de uma metodologia analítica com bom desempenho, mais barata e fácil de manipular e que fosse amiga do ambiente. Para o desenvolvimento da metodologia utilizou-se a microextração adsortiva em barra (BAμE) seguida de análise por cromatografia líquida de alta eficiência deteção por rede de díodos (HPLC-DAD) para a determinação de 8 benzofenonas (benzofenona (BPH), 2,4-dihidroxibenzofenona (BP-1), 2,2',4,4'-tetrahidroxibenzofenona (BP-2), 2-hidroxi-4-metoxibenzofenona (BP-3), 5-cloro-2-hidroxibenzofenona (BP-7), 2,2'-dihidroxi-4-metoxibenzofenona (BP-8), 3-hidroxibenzofenona (3HBP) e 4-hidroxibenzofenona (4HBP)) em matrizes ambientais e produtos cosméticos.
A metodologia otimizada permitiu obter limites de deteção entre 0,10 e 1,00 μg L-1 e de quantificação entre 0,33 e 3,33 μg L-1, boa linearidade com coeficiente de determinação superior a 0,99 e recuperações compreendidas entre 50 e 85 %.
A aplicação da metodologia em amostras reais permitiu determinar três benzofenonas (BPH, 3HBP e 4HBP) em diversas matrizes ambientais. Foi possível quantificar a BPH (0,68 ± 0,73 a 2,34 ± 1,14 μg L-1) em água do mar, da praia fluvial, da albufeira artificial, da barragem, do estuário e residual. A 4HBP (0,87 ± 2,77 a 2,52 ± 2,36 μg L-1) em água da praia fluvial, da albufeira artificial e residual, enquanto a presença da 3HBP foi apenas detetada em água residual (7,85 ± 2,42 μg L-1). Confirmou-se também a presença da BP-3 em dois cosméticos diferentes (72,33 ± 6,02 e 18,13 ± 1,46 μg mg-1).
A metodologia demonstrou ser uma alternativa mais ecológica, fácil e simples de manipular, associado a um baixo custo.
Emerging environmental contaminants are a threat to the ecosystem and their monitoring is crucial. Scientific development represents a big step towards the detection of hazardous substances to the environment, however it is necessary that the techniques have a high sensitivity and that they are in accordance with the principles of Green Analytical Chemistry. The present dissertation consisted in the development of an analytical methodology with good performance, cheaper and easier to handle and that was environmentally friendly. For the development of the methodology, bar adsorptive microextraction (BAμE) was used followed by analysis by high performance liquid chromatography diode-array detector (HPLC-DAD) for the determination of 8 benzophenones (benzophenone (BPH), 2,4-dihydroxybenzophenone (BP-1), 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 5-chloro-2-hydroxybenzophenone (BP-7), 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), 3-hydroxybenzophenone (3HBP) and 4-hydroxybenzophenone (4HBP)) in environmental matrices and cosmetic products. The optimized methodology allowed to obtain detection limits between 0.10 and 1.00 μg L-1 and quantification between 0.33 and 3.33 μg L-1, good linearity with a coefficient of determination above 0.99 and recoveries between 50 and 85%. The application of the methodology in real samples allowed the determination of three benzophenones (BPH, 3HBP and 4HBP) in different environmental matrices. It was possible to quantify BPH (0.68 ± 0.73 to 2.34 ± 1.14 μg L-1) in sea water, river beach, artificial reservoir, dam, estuary, and residual water. 4HBP (0.87 ± 2.77 to 2.52 ± 2.36 μg L-1) in water from the river beach, artificial reservoirs, and residual, while the presence of 3HBP was only detected in residual water (7.85 ± 2.42 μg L-1). The presence of BP-3 was also confirmed in two different cosmetics (72.33 ± 6.02 and 18.13 ± 1.46 μg mg-1). The methodology proved to be a more ecological alternative, easy and simple to handle, associated with a low cost.
Emerging environmental contaminants are a threat to the ecosystem and their monitoring is crucial. Scientific development represents a big step towards the detection of hazardous substances to the environment, however it is necessary that the techniques have a high sensitivity and that they are in accordance with the principles of Green Analytical Chemistry. The present dissertation consisted in the development of an analytical methodology with good performance, cheaper and easier to handle and that was environmentally friendly. For the development of the methodology, bar adsorptive microextraction (BAμE) was used followed by analysis by high performance liquid chromatography diode-array detector (HPLC-DAD) for the determination of 8 benzophenones (benzophenone (BPH), 2,4-dihydroxybenzophenone (BP-1), 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 5-chloro-2-hydroxybenzophenone (BP-7), 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), 3-hydroxybenzophenone (3HBP) and 4-hydroxybenzophenone (4HBP)) in environmental matrices and cosmetic products. The optimized methodology allowed to obtain detection limits between 0.10 and 1.00 μg L-1 and quantification between 0.33 and 3.33 μg L-1, good linearity with a coefficient of determination above 0.99 and recoveries between 50 and 85%. The application of the methodology in real samples allowed the determination of three benzophenones (BPH, 3HBP and 4HBP) in different environmental matrices. It was possible to quantify BPH (0.68 ± 0.73 to 2.34 ± 1.14 μg L-1) in sea water, river beach, artificial reservoir, dam, estuary, and residual water. 4HBP (0.87 ± 2.77 to 2.52 ± 2.36 μg L-1) in water from the river beach, artificial reservoirs, and residual, while the presence of 3HBP was only detected in residual water (7.85 ± 2.42 μg L-1). The presence of BP-3 was also confirmed in two different cosmetics (72.33 ± 6.02 and 18.13 ± 1.46 μg mg-1). The methodology proved to be a more ecological alternative, easy and simple to handle, associated with a low cost.
Description
Dissertação para obtenção do grau de Mestre no Instituto Universitário Egas Moniz
Keywords
Contaminantes emergentes Benzofenonas Matrizes ambientais BAμE HPLC-DAD