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The fate and effects of sewage-derived pharmaceuticals in soilGielen, Gertruda Jacqueline Hariette Petronella January 2007 (has links)
The behaviour and impact of pharmaceuticals in the environment are still poorly understood. Pharmaceuticals are widely used and continually released into the environment causing increasing concerns about their impact on the environment beyond the intended human or veterinary use. Prescribed pharmaceuticals, typically, enter the environment either through excretion after human use or disposal of surplus medication. Sewage treatment plants do not completely remove pharmaceuticals and their metabolites and these have been detected in sewage treatment plant effluent and receiving waters. Land application of treated sewage effluent is widely practiced in New Zealand as an alternative to surface water discharge. Methods were developed to determine selected pharmaceuticals in environmental matrices such as sewage effluent, sewage solids, soil, and soil water. From these, pharmaceutical removal efficiencies were determined for three common sewage treatment processes; activated sludge, composting and land application of sewage effluent. The impacts of some common pharmaceuticals on soil microbial communities, together with the effect of prolonged exposure to sewage effluent on these communities were examined. Additionally, toxicity of sewage effluent, and toxicity mechanisms of specific pharmaceuticals were investigated using luminescent micro-organisms and lettuce seedlings. Pharmaceuticals were successfully detected in sewage effluent, sewage solids, compost, soil and soil water. The sewage treatment processes investigated, including land application, were able to remove or reduce pharmaceutical concentrations in sewage. In case of land application, volcanic soils were more efficient than sandy soils in pharmaceutical removal while irrigation rate and level of sewage pre-treatment also showed some effect on removal efficiency. Pharmaceuticals were not acutely toxic at environmental levels currently detected. Exposure of microbial communities to unnaturally high levels of pharmaceuticals did demonstrate that most pharmaceuticals were potentially able to induce stress in the microbial community although microbes were able to metabolise some of these pharmaceuticals. Twelve years of effluent irrigation resulted in microbial adaptation to aspirin, acetaminophen and tetracycline, indicating that these pharmaceuticals had an effect on microbial community. Presently, land application of treated sewage waste may be a suitable treatment for additional pharmaceutical removal provided that land application schemes are designed appropriately, and pharmaceutical accumulation in the soil is occasionally monitored. It would be prudent to recognise the potential risk that could be caused by chronic exposure to pharmaceuticals such that continued vigilance may lead to future indications of chronic effects at an early stage.
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Synthèse de polymères à empreintes moléculaires d'alcaloïdes Vinca pour leur extraction sur phase solide dans des extraits de plantes ou des fluides biologiques : développement du détecteur conductimétrique sans contact à couplage capacitif et de la technique de la double injection en électrophorèse capillaire / Synthesis of molecularly imprinted polymers of Vinca alkaloids for their solid phase extraction in plants extracts or biological fluids : development of the capacitively coupled contactless conductivity detector and of the double injection in capillary electrophoresisLopez, Claire 09 December 2010 (has links)
Ce mémoire reporte dans une première partie les études menées sur des polymères à empreintes moléculaires (MIP) en extraction solide-liquide (SPE). La nature des interactions polymère-analyte, l’influence de la composition de la matrice de l’échantillon et la sélectivité des MIPs sont étudiés.La première application concerne l’extraction de molécules ciblées dans un extrait de plante. Deux MIPs respectivement préparés à partir de l’acide méthacrylique (MAA) et l’acide itaconique (IA) et avec respectivement la catharanthine et la vindoline comme molécule empreinte ont montré leur sélectivité sur des solutions standards puis sur un extrait de plante. Des expériences de réactivité croisée réalisées sur des molécules analogues à la molécule empreinte (alcaloïdes dimères) montrent la spécificité de reconnaissance des analytes par les MIPs. Le MIP-catharanthine est caractérisé par les isothermes de Scatchard et sa capacité est évaluée en SPE à partir de l’extrait de Catharanthus roseus. Un MIP préparé à partir de MAA avec la vinorelbine comme molécule empreinte a été appliqué à des matrices aqueuses salines pour l’extraction de la vinflunine et de son métabolite dans du plasma bovin et de l’urine. Des rendements d’extraction élevés ont été atteints grâce à une étude de l’impact des sels et au choix de solvants de lavage adaptés à la matrice. Une deuxième partie montre la simplicité d’utilisation et la sensibilité de la détection conductimétrique sans contact à couplage capacitif (C4D) lors de l’analyse du contre-ion et du principe actif dans des composés pharmaceutiques en électrophorèse capillaire (EC). La technique de la double injection a permis l’analyse simultanée des cations et des anions. La méthode EC-C4D développée est appliquée aux alcaloïdes Vinca et à différents médicaments avec des contre-ions anioniques ou cationiques. / This thesis reports in a first part results obtained with molecularly imprinted polymers (MIP) during solid liquid extraction. Polymer-analyte interactions, composition of the sample matrix and selectivity of MIPs have been studied.The first application concerned the extraction of molecules in a plant extract. Two MIPs respectively prepared from the methacrylic acid (MAA) and itaconic acid ( IA) and with respectively catharanthine and vindoline as template showed their selectivity on standard solutions then on a plant extract. Experiments of cross reactivity performed with analogue of the template (dimers alkaloids) have proved the specificity of analytes recognition by the MIPs. The MIP-catharanthine is characterized by Scatchard isotherms and its capacity was estimated from the extract of Catharanthus roseus. A MIP prepared from MAA with the vinorelbine as template was applied in salt aqueous matrices for the extraction of vinflunine and its metabolite in bovine plasma and urine. High extraction recoveries were reached with a study of the impact of salts and the choice of washing solvents adapted to the matrix. The second part showed the simplicity of use and the sensibility of capacitively coupled contactless conductivity detection (C4D) for the analysis of counter-ion and active principle in pharmaceutical compounds in capillary electrophoresis (CE). The technique of double injection allowed the simultaneous analysis of cations and anions. The developed method EC-C4D was applied to Vinca alkaloids and various medicines with anionic or cationic counter-ions.
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Avaliação de diferentes sorventes para extração em fase sólida de pesticidas em águaSantos, Alex Sandro Magno de São José 24 September 2010 (has links)
In this work a method using solid phase extraction (SPE) and gas chromatography coupled to mass spectrometry (GC/MS) for determination of pyrimethanil, flumetralin and krexosim-methyl from water was developed. Different commercial
sorvents were evaluated (C18, ENVI-Carb, Florisil, silica and ENVI-Carb/LC-NH2) at concentration level of 2.5 μg L-1 (three replicates). The best results were obtained using C18, with recovery values of 102.3, 79.0 and 89.0 % for pyrimethanil, flumetralin and kresoxim-methyl, respectively. Therefore, the validation of the method was carried out with C18 sorvent. Recovery experiments were carried out (seven replicates), at three fortification levels (0.5, 2.5 and 5.0 μg L-1), resulting in recoveries in a range of 62.6 to 104.6 % and relative standard deviations between 5.1 and 15.5 %. Detection and quantification limits ranged from 0.002 to 0.005 μg L-1 and from 0.007 to 0.147 μg L-1, respectively, for the different pesticides studied. The developed method was linear over the range assayed, 0.05-4.0 μg mL-1, with correlation coefficients above of 0.99. Next, peat was tested for solid-phase extraction of these pesticides from water. Recovery experiments were carried out (three replicates) at fortification level of 2.5 μg L-1, resulting in recoveries of 41.1, 95.9 and 88.3 % for pyrimethanil, flumetralin and kresoxim-methyl, respectively. Results have shown that the peat material can be successfully applied for analysis of flumetralin and kresoxim-methyl in water. The procedure developed was applied to
the determination of these pesticides in drinking water sample. No pesticide residues, at concentrations above the limit of detection, were found in the sample. / A contaminação da água preocupa devido a sua grande importância para as formas de vida, em especial a humana, gerando a necessidade de um controle na contaminação das águas potável, de irrigação, de superfície, subterrâneas ou de
efluentes industriais. Justifica-se assim a importância na determinação de resíduos de pesticidas em água. Neste trabalho foi desenvolvido e validado um método analítico
utilizando a técnica de extração em fase sólida (EFS), com a avaliação da eficiência de diferentes sorventes para extração de resíduos dos pesticidas pirimetanil, flumetralina e cresoxim-metílico de água e análise por cromatografia a gás acoplada
a espectrometria de massas (CG/EM). Foram avaliados os sorventes comerciais: C18, ENVI-Carb (carbono grafitinizado), Florisil, sílica e ENVI-Carb/LC-NH2 (resina polimérica do aminopropil), para o nível de fortificação de 2,5 μg L-1 em triplicata. A fase C18 apresentou os melhores valores de recuperação para pirimetanil, flumetralina e cresoxim-metílico, com os valores 102,3; 79,0 e 89,0 %, respectivamente. A
validação do método foi realizada com o sorvente comercial C18. O estudo da recuperação dos pesticidas, em uma série de sete replicatas, mostrou valores de recuperação que variaram entre 62,6 e 104,6 % para os níveis de fortificação de 0,5, 2,5 e 5,0 μg L-1, com desvio padrão relativo entre 5,1 e 15,5 %, limite de detecção entre 0,002 e 0,044 μg L-1 e limite de quantificação entre 0,007 e 0,147 μg L-1. A
curva analítica foi feita no extrato da matriz com os seguintes valores de concentração dos pesticidas: 0,05; 0,1; 0,2; 0,5; 1,0; 2,0; 3,0; 4,0 μg mL-1 e apresentou r acima de 0,99. Em seguida, foi avaliada a turfa como sorvente para o nível de fortificação de 2,5 μg L-1 em triplicata. Os valores de recuperação para pirimetanil, flumetralina e cresoxim-metílico foram de 41,1; 95,9 e 88,3 %, respectivamente, sendo, portanto uma alternativa viável e de baixo custo para a
extração dos pesticidas flumetralina e cresoxim-metílico de água. O método foi aplicado em amostra de água potável, utilizando como sorventes C18 e turfa, sendo que não foram detectados resíduos de pesticidas considerando os limites de detecção do método.
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Desenvolvimento e validação da metodologia SPE-LC-MS/MS para a determinação de fármacos e droga de abuso nas águas da represa Guarapiranga - São Paulo/SP, Brasil / Development and validation of methodology SPE-LC-MS/MS for pharmaceuticals and illicit drug determination in the waters of Guarapiranga dam - Sao Paulo/SP, BrazilHelena Miho Shihomatsu 18 March 2015 (has links)
Este estudo apresenta o desenvolvimento da metodologia de extração em fase sólida e separação em cromatográfica líquida acoplada a espectrometria de massas em sequencia, SPE-LC-MS/MS, para a determinação de 21 (vinte e um) fármacos pertencentes a diferentes classes terapeuticas, 1 (uma) droga de abuso e seu principal metabólito, em amostras de água superficial. A separação cromatográfica foi otimizada estudando o desempenho de fases estacionárias e fases móvies. A quantificação dos compostos selecionados foi realizada com a ionização por eletronebulização (electrospray ionization- ESI) e o espectrômetro de massas operando no modo de Monitoramento de Múltiplas Reações (Multiplas Reaction Monitoring- MRM). A validação da metodologia proposta foi realizada utilizando os parâmetros de seletividade, efeito de matriz, faixa de trabalho, linearidade, limites de detecção (LD) e quantificação (LQ), precisão, exatidão, recuperação e robustez. A validação da metodologia permitiu a sua aplicação na avaliação da distribuição dos 23 compostos selecionados, nas águas da represa Guarapiranga, um dos principais sistemas produtor de água potável da Região Metropolitana de São Paulo (RMSP). A presença desses poluentes nos ambientes aquáticos é proveniente da liberação direta do esgoto urbano das habitações do seu entorno, como consequência do precário sistema de saneamento básico. As águas da represa Guarapiranga foram avaliadas em 14 (quatorze) locais estrategicamente escolhidos e amostradas durante 3 (três) campanhas de coleta de amostra (agosto de 2011, setembro de 2012 e abril de 2013). Nessas amostras foram quantificados acetaminofeno (9,6 - 254 ng L-1), atenolol (8,5 177 ng L-1), benzoilegonina (7,9 139 ng L-1), cafeína (27 27386 ng L-1), carbamazepina (12 358 ng L-1), clortalidona (9,4 35 ng L-1), cocaína (12,8 2650 ng L-1), diclofenaco (8 35 ng L-1), enalapril (20 ng L-1), losartana (6,7 114 ng L-1) e valsartana (9,7 - 47 ng L-1). O ponto de coleta denominado de GU103-12 (23°4188.5S 46°4467.3W) foi a região que apresentou os valores mais elevados quanto ao nível de concentração dos compostos avaliados e ao índice de risco integrado de poluição química aquática (Integrated Risk Index of Chemical Aquatic Pollution IRICAP). O estudo também foi realizado em amostras de água de reservatórios das Unidades de Gerenciamento de Recursos Hídricos (UGRHI) 5 e 6 do Estado de São Paulo. Os resultados demonstraram que o uso e a ocupação do solo influenciam diretamente na qualidade da água dos reservatórios, evidenciando a necessidade de implementar melhorias no sistema de coleta de esgoto e de ocupação irregular para evitar a contaminação e o descarte inadequado em ambientes aquáticos. / This study presents the development of the methodology of solid phase extraction and liquid chromatography - tandem mass spectrometry, SPE-LC-MS/MS, for the determination of 21 (twenty one) pharmaceuticals belonging to different therapeutic groups, 1 (one) illicit drug and its major metabolite, in surface water samples. The chromatographic separation was optimized by studying the performance of different stationary and mobile phases. Quantitation of selected compounds was performed by electrospray ionization (ESI) and the mass spectrometer operating in a multiple reaction monitoring (MRM) mode. The validation of the proposed methodology was performed using the parameters of selectivity, matrix effect, dynamic range, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, accuracy, recovery and robustness. The validation of methodology allowed to apply the methodology in the evaluation of the distribution of the 23 (twenty one) selected compounds, in Guarapiranga Dam waters, an of the major producer system of drinking water of the Metropolitan Region of São Paulo (MRSP). The presence of these pollutants in aquatic environments is from the direct release of urban sewage from the homes of your surroundings, as a result of poor sanitation system. The waters of Guarapiranga dam were evaluated in 14 (fourteen) locations strategically chosen and sampled in 3 (three) campaigns of sample collection (August 2011, September 2012 and April 2013). In these samples were quantified acetaminophen (9.6 - 254 ng L-1), atenolol (8.5 - 177 ng L-1), benzoylegonine (7.9 - 139 ng L-1), caffeine (27 - 27386 ng L-1) carbamazepine (12 - 358 ng L-1), chlorthalidone (9.4 - 35 ng L-1), cocaine (12.8 - 2560 ng L-1), diclofenac (8 - 36 ng L-1), enalapril (20 ng L-1), losartan (6.7 - 114 ng L-1) and valsartan (9.7 - 47 ng L-1). The sample siting GU103-12 (23°4188.5S 46°4467.3W) was the region with the highest values in the level of concentration of the target compounds and the integrated risk index of chemical aquatic pollution (IRICAP). The study was also conducted on water samples from reservoirs of the UGRHI (Unit of Water Resources Management) 5 and 6, State o São Paulo. The results showed that the use and occupation of land directly influence the reservoir water quality highlighting the need to implement improvements in sewage collection system and illegal occupation to prevent contamination and the improper disposal in aquatic environments.
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DESENVOLVIMENTO DE METODOLOGIA PARA ANÁLISE DE SULFONAMIDAS EM MEL UTILIZANDO CROMATOGRAFIA LÍQUIDA E DETECÇÃO POR ARRANJO DE DIODOS / DEVELOPMENT OF METHODOLOGY FOR ANALYSIS SULFONAMIDES IN HONEY USING LIQUID CHROMATOGRAPHY AND DETECTION DIODE ARRAYSilva, Verônica Alves Gonçalves da 16 June 2008 (has links)
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Previous issue date: 2008-06-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Honey is a natural substance produced by bees and by your nature it is considered a healthy
product. Presence of additives and/or preserve agents is not permitted. On apiculture,
sulfonamydes are largely used on prevention and control of beehive disease, such as
American foulbrood caused by Paenibacillus larvae. A consequence of this practice is the
presence of these residues in honey, that should cause allergy reactions on consumers. In the
last years, some publicated works is discussing the presence of antibiotic and sulfonamides
residues in honey. In Brazil, the presence of antibiotics residues in food is controled by the
Agência Nacional de Vigilância Sanitária (ANVISA) an by the Ministério da Agricultura,
Pecuária e do Abastecimento (MAPA). The realization of monitoring contaminants residues
in food programs, as well as the Plano Nacional de Controle de Resíduos (PNCR) from
MAPA are essentials to the sanitary vigilance actions development, preventing and
controlling possible hazard to the consumer health. This work has the objective the
development and validation of multiresidue analytical method to the sulfadiazine,
sulfathiazole, sulfadimedine and sulfadimethoxine determination in bee honey using high
performance liquid chromatography (HPLC) with diode array detector (DAD). The
established methodology consisted on such conditions: solid phase extraction with Nexus
sorbent, elution with acetonitrile 5 mL, and reconstitution with sodium acetate buffer (0,05
mol L-1) pH 4,5, with 1% methanol addition, separation on analytical column C18,
acetonitrile and water mobile phase, on gradient elution mode and detection on 278 nm. The
sample preparation consisted on the acid hydrolysis with hydrochloric acid 2 mol L-1 of a
honey rate and adjust to pH 4,5 with sodium acetate buffer solution 0,05 mol L-1 pH 4,5. The
method was validated and the results demonstrated accuracy and precision between the limits
established by the current legislation. Good linearity range was encountered, obtaining
recovery values varying from 41 to 89% and relative standard deviation estimative varying
between 2,36 and 14% to the four studied compounds. The four sulfonamides detection limits
in honey sample varying from 20 to 30 ^g kg-1 and the quantification limits varied from 60 to
90 ^g kg-1. Considering 100 ^g kg-1 the residue maximum limit established by the Brazilian
legislation to the SDZ, STZ, SMZ and SDM total concentration, the described method permit
suitable determination of the four sulfonamides in bee honey. / O mel é uma substância natural, produzida pelas abelhas e por sua natureza é considerado um
produto saudável, não sendo permitido a presença de aditivos e/ou agentes conservadores. Na
apicultura as sulfonamidas são muito utilizadas na prevenção e controle de doenças em
colméias, como a cria pútrida americana causada pelo Paenibacillus larvae. Uma
conseqüência desta prática é a presença destes resíduos no mel, o que pode causar reações
alérgicas nos consumidores. Nos últimos anos, alguns trabalhos na literatura vêm discutindo a
presença de resíduos de antibióticos e sulfonamidas no mel. No Brasil, a presença de resíduos
de antibióticos nos alimentos é controlada pela Agência Nacional de Vigilância Sanitária
(ANVISA) e pelo Ministério da Agricultura, Pecuária e do Abastecimento (MAPA). A
realização de programas de monitoramentos de resíduos de contaminantes em alimentos,
assim como o Plano Nacional de Controle de Resíduos (PNCR) do MAPA são essenciais para
que ações de vigilância sanitária possam ser desenvolvidas, prevenindo e controlando
possíveis danos à saúde do consumidor. Este trabalho tem por objetivo desenvolver e validar
um método analítico multiresidual para a determinação de sulfadiazina, sulfatiazol,
sulfadimidina e sulfadimetoxina em mel de abelhas usando cromatografia líquida de alta
eficiência (CLAE) com detector de arranjo de fotodiodos (DAD). A metodologia estabelecida
consistiu nas seguintes condições: extração em fase sólida com sorvente Nexus, eluição com 5
mL de acetonitrila e reconstituição com solução-tampão acetato de sódio (0,05 mol L-1) pH
4,5, com adição de 1% de metanol, separação em coluna analítica C18, fase móvel acetonitrila
e água, no modo de eluição em gradiente e detecção a 278 nm. O preparo de amostra consistiu
na hidrólise ácida com ácido clorídrico 2 mol L-1 de uma alíquota de mel e ajuste para pH 4,5
com solução tampão acetato de sódio 0,05 mol L-1 pH 4,5. O método foi validado e os
resultados demonstraram exatidão e precisão dentro dos limites estabelecidos pela legislação
vigente. Foi encontrada boa faixa de linearidade, obtendo-se valores de recuperação que
variaram de 41 a 89% e estimativa do desvio padrão relativo variando entre 2,36 e 14% para
os quatro compostos estudados. Os limites de detecção das quatro sulfas em amostra de mel
variaram de 20 a 30 ^g kg-1 e os limites de quantificação variaram de 60 a 90 ^g kg-1.
Considerando o limite máximo de resíduo estabelecido pela legislação brasileira de 100 ^g
kg-1 para as concentrações totais de SDZ, STZ, SMZ e SDM, o método descrito permite
adequada determinação das quatro sulfas em amostras de mel de abelhas.
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DESENVOLVIMENTO DE MÉTODO MULTIRESIDUAL PARA ANÁLISE DE PESTICIDAS EM MEL, UTILIZANDO CROMATOGRAFIA A LÍQUÍDO COM DETECTOR ESPECTROFOTOMÉTRICO COM ARRANJO DE DIODOS / MULTIRESIDUAL METHOD DEVELOPMENT TO ANALYSIS OF PESTICIDES IN HONEY, USING LIQUID CHROMATOGRAPHY WITH SPECTROPHOTOMETRIC DETECTOR WITH ARRANGEMENT OF DIODESSilva, Marconiel Neto da 30 January 2009 (has links)
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Previous issue date: 2009-01-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Honey is a product of proven therapeutic and nutritional properties, and which may act as an excellent bioindicator, given the way the bees gather and process the raw material used in its preparation. The monitoring of pesticide residues in honey is important both to control product quality in domestic and international markets, and in assessing the potential for contamination in areas near agricultural crops. Considering these facts, we developed a method for analyzing carbamate insecticides (carbaryl and carbofuran), organochlorine (aldrin and dieldrin), organophosphates (dimethoate and parathion methyl) and pyrethroid (permethrin), and the group of anilides herbicide (propanil) and fenoxiácidos (2,4-D) in honey. Hence, in this work the analytical conditions were established for the proper determination of residues of pesticides cited using the technique of solid phase extraction and liquid chromatography with UV detection with a diode array. The study aimed to compare different analytical conditions for the determination of pesticides, looking for better separation, sensitivity, precision and accuracy in the determination of pesticide residues in samples of honey bees. Standard solutions at concentrations ranging from 1.0 to 20.0 μ g mL-1 were evaluated in different mobile phases, using a C18 column (250 x 4.6 mm id, 5 μ m). The mobile phase composition more suitable was acetonitrile: water at pH 3.0 (acidified with acetic acid) in gradient mode, for monitoring the compounds at a wavelength of 220 nm. In the established conditions, except for aldrin and dieldrin and dimeotate, it was observed recoveries between 75.26% and 113.58%, with variation Coefficients Between 2.16% and 11.31% for concentration levels raging from 0:10 to 1.00 μ gg-1 (correlation coefficients between 0.9978 and 0.9998). Recoveries lower than 50% to the cited insecticides were observed when using ethyl acetate solvent extractor and the solvent elution by ethyl acetate, in such a way new studies can be done to obtain better recoveries for these compounds. / O mel é um produto de reconhecidas propriedades nutritivas e terapêuticas e, o qual pode atuar como um excelente bioindicador, dada à forma como as abelhas recolhem e processam a matéria-prima utilizada na sua elaboração. O monitoramento de resíduos de pesticidas no mel é importante, tanto para o controle de qualidade do produto nos mercados nacional e internacional, quanto na avaliação do potencial de contaminação em áreas próximas a cultivos agrícolas. Considerando tais fatos, foi desenvolvido um método para análise dos inseticidas carbamatos (carbaril e carbofurano), organoclorados (aldrin e dieldrin), organofosforados (dimetoato e parationa metílica) e piretróide (permetrina), além do herbicida do grupo das anilidas (propanil) e fenoxiácidos (2,4-D) em mel. Para tanto, neste trabalho foram estabelecidas condições analíticas para a adequada determinação dos resíduos dos citados pesticidas utilizando a técnica de extração em fase solida e cromatografia líquida com detecção espectrofotométrica com arranjo de diodos. O trabalho teve como objetivo comparar diferentes condições analíticas para a determinação dos pesticidas, buscando-se melhor separação, sensibilidade, precisão e exatidão na determinação de resíduos dos pesticidas em amostras de mel de abelhas. Soluções-padrão em concentrações variando de 1,0 a 20,0 μg mL-1 foram avaliadas em diferentes fases móveis, utilizando-se coluna C18 (250 x 4.6 mm d.i., 5 μm). A composição da fase móvel mais adequada foi acetonitrila:água em pH 3,0 (acidificada com ácido acético), em modo gradiente, monitorando-se os compostos em comprimento de onda de 220 nm. Nas condições estabelecidas, excetuando-se aldrin, dieldrin e dimetoato, foram observadas recuperações entre 75,26% a 113,58%, com coeficientes de variação entre 2,16% a 11,31%, para níveis de concentração entre 0,10 a 1,00 μg.g-1 (coeficientes de correlação entre 0,9978 e 0,9998). Recuperações inferiores a 50 % foram, entretanto, observadas para os citados inseticidas, utilizando-se solvente extrator acetato de etila e eluição com acetato de etila, sendo necessários novos estudos para obtenção de melhores recuperações para tais compostos.
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Investigação das condições de crescimento e produção de metabólitos secundários das linhagens de fungos Penicillium citrinum e Penicillium oxalicum / Investigation of conditions for growth and production of secondary metabolites of fungi strains P. citrinum and P. oxalicumEli Fernando Pimenta 01 October 2010 (has links)
No presente estudo, duas espécies de fungos isoladas do ambiente marinho tiveram seus extratos brutos ativos contra Staphylococcus aureus e Candida albicans para uma espécie de P. citrinum e, atividade citotóxica e contra Mycobacterium tuberculosis para uma espécie de P. oxalicum. Estas foram estudadas com a finalidade de otimizar suas condições de crescimento para produção de metabólitos secundários. Foram realizadas análises multivariadas utilizando planejamento fatorial fracionário. Foram obtidas duas condições ótimas de crescimento para as duas linhagens de Penicillium. O crescimento em maior volume em condições de cultura otimizadas para P. oxalicum permitiu observar a presença de três metabólitos secundários no extrato do meio de cultura. Dois puderam ser isolados e identificados: a meleagrina 52 e a oxalina 26. A metodologia utilizada para se obter uma maior quantidade de metabólitos secundários proporcionou, ainda, o incremento em cerca de 150% na área do pico da oxalina. A partir do crescimento em maior volume em condições de cultura otimizadas para P. citrinum foi possível observar presença de pelo menos onze diferentes metabólitos na análise dos extratos obtidos do meio de cultura. Foi possível identificar e isolar quatro compostos já conhecidos: a (8E)-1-(2,3-diidropirrol-1-il)-2-metildec-8-eno-1,3-diona 56; a 1-(2,3-diidropirrol-1-il)-2-metildecano-1,3-diona 58; a 2-((E)-hept-5-enil)-6,7,8,8a-tetraidro-3-metilpirrolo[2,1-b][1,3]oxazin-4-ona 59 e a citrinina 31. Também foram isolados dois novos alcalóides indólicos contendo um grupo nitro na molécula que foram nomeadas de citrinalinas A 60 e B 62. Foi realizado, também, um estudo com P. citrinum visando a maior produção das citrinalinas, que possibilitou o incremento na produção da citrinalina B. / In this study, two species of fungi isolated from the marine environment had their active extracts against Staphylococcus aureus and Candida albicans to a strain of P. citrinum, and activity cytotoxic and against Mycobacterium tuberculosis to a strain of P. oxalicum. This studied aims the optimization their growth conditions for the production of secondary metabolites. Multivariate analysis using a fractional factorial design were used to establish optimal growth conditions for both Penicillium strains. Two optimal growth conditions were obtained for both Penicillium strains. A largest growth volume of P. oxalicum using optimized conditions enabled the detection of three secondary metabolites in the culture media crude extract. Two of such compounds were isolated and identified: meleagrin 52 and oxaline 26. The methodology used to increase the production of secondary metabolites by P. citrinum enabled an increase of 150% in the peak area of oxaline. A largest growth volume of P. citrinum led to the detection of eleven different metabolites in the culture media. Four of these compounds were isolated and identified as the known (8E)-1-(2,3-dihydropyrrol-1-yl)-2-methyldec-8-ene-1,3-dione 56; the 1-(2,3-dihydropyrrol-1-yl)-2-methyldecane-1,3-dione 58; the 2-((E)-hept-5-enyl)-6,7,8,8a-tetrahydro-3-methylpyrrolo[2,1-b][1,3]oxazin-4-one 59 and citrinin 31. Two new indole alkaloids containing a nitro group were also isolated and identified, named citrinalins A 60 and B 62. A further study with P. citrinum aiming an enhanced production of citrinalins allowed a significant increase in the production of citrinalin B.
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Síntese de polímeros de impressão molecular e sua aplicação na técnica de extração em fase sólidaPeçanha, Bruna Rachel de Britto 23 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-23T19:00:13Z
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Peçanha, Bruna Rachel de Britto [Dissertação, 2012].pdf: 3907379 bytes, checksum: f2acabc3c1c39363b86f0d651d6b5936 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Polímeros de impressão molecular (MIPs) foram sintetizados e aplicados
como adsorventes na técnica de extração em fase sólida (EFS). O método de
polimerização por precipitação foi utilizado para a síntese dos polímeros, devido à
simplicidade de preparo, altos rendimentos e obtenção de partículas mais uniformes,
devido a não trituração do polímero. O MIP foi sintetizado com ácido metacrílico
(MAA) como monômero funcional, trimetacrilato de trimetilolpropano (TRIM) e
dimetacrilato de etilenoglicol (EDMA) como agentes de reticulação e o cloridrato de
amilorida (AMI) foi escolhido como molécula-molde. Diferentes proporções de MAA,
TRIM, EDMA, volume e tipo de solvente foram utilizadas para ajuste das condições
ideais de síntese. Os MIP foram avaliados quanto à capacidade de adsorção
comparando-se a polímeros sintetizados na ausência da molécula-molde (NIP,
polímeros não impressos). O solvente de elevada polaridade empregado na síntese
(THF:MeOH:H2O) permitiu o emprego da técnica para moléculas polares como AMI.
O controle no volume de solvente permitiu a obtenção de partículas maiores, de
modo que a EFS foi realizada em condições usuais, o que confere um potencial para
aplicação dessa técnica de polimerização na preparação de adsorventes para EFS.
O polímero que apresentou maior capacidade adsortiva no ensaio realizado em
tampão citrato-acetato pH 6,5 foi o MIP/NIP 12 (AMI:MAA:TRIM 1:8:10), com uma
taxa média de adsorção de 83 e 88% para NIP e MIP, respectivamente. A adsorção
foi elevada devido a interação iônica entre MAA e AMI promovida pelo controle de
pH, porém foi não específica. O polímero MIP/NIP 12 foi aplicado como adsorvente
na EFS, onde a recuperação de AMI foi avaliada nos resíduos de carregamento e
eluição com solventes. O carregamento com tampão citrato-acetato pH 6,5 foi o
ideal, favorecendo a interação iônica do polímero com o analito. A eluição total de
AMI do cartucho somente ocorre após lavagem com o solvente na presença de
ácido, que protona os grupos carboxila do polímero, rompendo assim a interação
iônica com o analito / Molecularly imprinted polymers (MIPs) were synthesized and applied as
adsorbents in solid-phase extraction technique (SPE). The polymers have been
synthesized by precipitation polymerization method because of its simplicity, high
yields and good control of final size and shape of particles. MIP was synthesized
using methacrylic acid (MAA) as functional monomer, trimethylolpropane
trimethacrylate (TRIM) and ethyleneglycol dimethacrylate (EDMA) as cross-linker
and amiloride hydrochloride (AMI) was chosen as template. Different ratios of MAA,
TRIM and EDMA, volume and type of solvent were used to adjust the optimal
synthesis conditions. The MIP were tested for adsorption capacity compared to the
polymers synthesized in the absence of template molecule (NIP, non-imprinted
polymers). The polar solvent mixture used (THF:MeOH:H2O) allowed the synthesis of
MIP of polar molecules as AMI. The solvent volume control afforded the larger
particles so the SPE was performed in the usual conditions, giving a potential
application for this polymerization technique in the preparation of adsorbents for
SPE. The polymers with higher adsorption capacity at the test performed in citrateacetate
buffer pH 6,5 was MIP/NIP 12 (AMI:MAA:TRIM 1:8:10) with adsorption rate
of 83 and 88% for NIP and MIP, respectively. The recognition of MIP was due to ionic
interaction between MAA and AMI promoted by pH control, but was not specific. The
polymer MIP/NIP 12 was used as a solid-phase extraction sorbent and the recoveries
of AMI was evaluated using different loading and elution conditions. The loading with
buffer citrate-acetate pH 6,5 was optimal, due to ionic interaction of the polymer with
the analyte. Total elution of AMI bound to the polymers only occurs after washing
with a acid-containing solvent, because of protonation of the carboxyl groups of the
polymer and disrupting the ionic interaction with the analyte
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Tenzidy v povrchových a odpadních vodách / Surfactants in Surface and Waste WaterŠtefka, Michal January 2017 (has links)
This work is focused on the occurrence of surface-active substances in the environment. It deals with the development and optimization of methods for the determination of selected surfactants in samples from rivers and from influent and effluent of wastewater treatment plants. Representatives of anionic, nonionic and zwitterionic surfactants were selected as target compounds. Based on optimization of analytical methods and their pilot testing abroad on samples of surface water, the selection of analytes for the conditions in the Czech Republic were corrected and operatively expanded. For the final analysis liquid chromatography with mass spectrometry was used. Analysis of cationic surfactants was realized using liquid chromatograph with UV-VIS detector. This optimized method for analysis of anionic surfactants was applied to real samples. Samples of surface running water were from the River Thurso in Scotland and then from watercourses in the catchment area of Moravia river were collected. In addition to the grab sampling also continuous weekly sampling of water from Tvaroženský potok and Litava was realized. Waste water was collected at inflow and outflow of three wastewater treatment plants (WWTP) in South Moravia (Brno – Modřice, Břeclav and Hodonín).
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Molecularly imprinted polymers as selective sorbents for recognition in complex aqueous samples / Polymères à empreintes moléculaires en tant qu’adsorbants sélectifs pour la reconnaissance dans des milieux aqueux complexesNestora, Sofia 13 April 2017 (has links)
Dans cette thèse, nous avons démontré la faisabilité de la préparation de polymères à empreinte moléculaires (MIP) hautement sélectifs pour la reconnaissance dans des matrices aqueuses complexes avec des applications dans les cosmétiques et en technologie alimentaire. Les MIP (de l'anglais molecularly imprinted polymers) sont des récepteurs synthétiques comparables aux anticorps, qui sont synthétisés par co-polymérisation de monomères fonctionnels et réticulants en présence d'un gabarit moléculaire. Leurs propriétés de reconnaissance moléculaire, associées à leur grande stabilité, robustesse mécanique, faible coût et leur synthèse facile les rendent extrêmement intéressants comme matériaux de capture sélective, avec des applications dans les séparations analytiques, la détection et la vectorisation des médicaments. Cependant, leur reconnaissance sélective dans des milieux aqueux reste toujours problématique et c'est l'une des raisons de leur expansion commerciale restreinte. Dans une première partie, nous avons développé un MIP fonctionnant en milieu aqueux pour son application comme ingrédient actif dans un déodorant. Les odeurs corporelles sont principalement dues à des acides gras volatils générés à partir de leurs précurseurs, des conjugués de glutamine par des enzymes hydrolytiques produites à partir de bactéries présentes sur la peau. La plupart des anti-transpirants et des déodorants actuellement commercialisés contiennent des sels d'aluminium et des agents antibactériens non spécifiques, respectivement. Cependant, l'utilisation extrêmement étendue de ces produits nécessite des solutions alternatives en ce qui concerne divers problèmes (environnement, respect de l'écosystème de la peau, toxicité, etc.). Pour cette raison, un MIP a été synthétisé pour capturer les précurseurs conjugués de glutamine afin qu'ils ne soient plus disponibles aux bactéries, empêchant ainsi leur transformation en composés malodorants. Afin de générer des liaisons sélectifs dans des environnements aqueux, un monomère à base d'amidinium qui peut former une interaction électrostatique stoechiométrique forte avec les groupes carboxyle sur le gabarit moléculaire a été synthétisé. Le MIP, mélangé dans une formulation dermo-cosmétique, pourrait capter sélectivement les précurseurs conjugués de glutamine, au milieu d'une multitude d'autres molécules présentes dans la sueur humaine. En outre, le MIP n’affecte pas les bactéries de la peau, ouvrant la voie à des déodorants innovateurs de nouvelle génération, moins problématiques pour la santé. Dans une deuxième partie, nous avons développé une procédure rapide et efficace basée sur l'extraction en phase solide à empreinte moléculaire (MISPE) pour la purification sélective de la bétanine et de son stéréoisomère l’isobétanine à partir d'extraits de betterave. La bétanine est un pigment naturel ayant un fort pouvoir antioxydant et dont les propriétés pharmacologiques sont de plus en plus étudiées. Ce pigment est actuellement utilisé comme simple colorant alimentaire. Dans notre étude, l'acide dipicolinique a été utilisé comme gabarit moléculaire pour la synthèse de MIP, en raison de sa similarité structurelle avec le groupe chromophore de la bétanine. Les procédures MISPE ont été optimisées permettant l'élimination presque complète des glucides issus de la matrice végétale ainsi que la majorité des protéines, ce qui permet d'obtenir un rendement élevé d'extraction de la bétanine / isobétanine en une seule étape. De plus, toute la procédure d'extraction a été réalisée dans des solvants respectueux de l'environnement, tels que l'éthanol ou l'eau. Pour conclure, nous sommes convaincus que ce travail pave le chemin au développement d'une nouvelle génération des MIP fonctionnant en milieu aqueux avec des propriétés de reconnaissance améliorées dans des environnements complexes, qui pourra s'appliquer également à d'autres domaines biotechnologiques et biomédicaux. / In this thesis, we have demonstrated the feasibility of preparing highly selective molecularly imprinted polymers (MIPs) for recognition in complex aqueous matrices with applications in cosmetics and food technology. MIPs are synthetic tailor-made receptors, with binding affinities and specificities comparable to those of natural antibodies. Their molecular recognition properties, combined with their high stability, mechanical robustness, low cost and easy synthesis make them extremely attractive as selective capture materials with applications in analytical and preparative separations, sensing and drug delivery, among others. However, their selective recognition in aqueous samples still remains problematic and is one of the reasons for their so far lilited commercial expansion. In the first part, we developed a water compatible MIP for its application as an active ingredient in a deodorant. Body odors are mainly due to volatile fatty acids generated from their glutamine conjugate precursors by hydrolytic enzymes from bacteria present on the skin. Most currently marketed anti-perspirants and deodorants contain, respectively aluminum salts and unspecific antibacterials. However, the extremely wide use of these products requires alternative solutions with regard to various problems (environmental, respect of skin ecosystem, toxicity, etc.). For this reason, a MIP was developed to capture the glutamine conjugate precursors so that they are no longer available to the bacteria, thus preventing their transformation to malodorous compounds. In order to generate binding selectivity in aqueous environments, an amidinium-based monomer which can form a strong stoichiometric electrostatic interaction with the carboxyl groups on the template, was synthesized. The MIP, blended in a dermo-cosmetic formulation, could capture selectively the glutamine precursors, amidst a multitude of other molecules present in human sweat. Furthermore, the MIP did not affect the skin bacteria, paving the way to an innovative and 'safer ' future-generation deodorant. In the second part, we developed a fast and efficient procedure based on molecularly imprinted solid phase extraction (MISPE) for the selective clean-up of betanin and its stereoisomer isobetanin from red beetroot extracts. Betanin is a natural pigment with significant antioxidant and biological activities currently used as food colorant. Dipicolinic acid was used as template for the MIP synthesis, because of its structural similarity to the chromophore group of betanin The MISPE procedures were optimized allowing the almost complete removal of carbohydrates and the majority of proteins, resulting in high extraction recovery of betanin / isobetanin in a single step. Moreover, the whole extraction procedure was performed in environmentally friendly solvents with either ethanol or water. To conclude, we believe that this study paves the way towards the development of a new generation of water compatible MIPs with improved recognition properties in highly complex aqueous environments, and should be applicable to other biotechnological and biomedical areas as well.
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