Determination of arsenic and selenium compounds in water samples organotin compounds in fish samples by LC-ICP-MS

none

A method for the determination of platinum group elements (PGEs) in natural tree samples was developed. An alumina column in-line with inductively coupled plasma mass spectrometry (ICP-MS) achieves the separation of interferents as well as pre-concentration of the analytes. The application of this proposed method on tree top samples displayed an effective separation of Ru, Rh, Re, Pd, Ir and Pt from the interferents, Ni, Cu and Zn for quantitative analysis of the analytes. The concentration data was compared to ICP-HRMS data and while it was difficult to determine whether the concentrations were in agreement or not, as both methods have a large degree of error. However, both methods displayed elevated concentrations of PGEs in areas over geological conductors in Rock Lake, Manitoba. This proposed method offers distinct advantages over previous on-line methods, as it is extended to include multiple PGEs as well as reduces sample consumption to a more suitable volume for natural samples. While the detection limit is higher than previous methods due to the lowered sample volume, it is still lower than the detection limits reported in commercial laboratories. / Thesis (Master, Chemistry) -- Queen's University, 2008-01-30 19:40:54.673 / Anglo American

No description available.

This study used LA-ICP-MS on a documented sample of modern teeth to sample from a continuous line across the cementum increments thus creating a temporal line graph of the elemental composition against distance. The knowledge of cementum was extended through (1) a more complete elemental composition analysis and (2) the relation of element distribution to the ultrastructure structure throughout the life of a tooth. This study was exploratory and demonstrated that lead, zinc, mercury, and barium follow the same general line of changes, and most likely represent changes in health and exposure to these metals in the general environment. Copper, manganese and vanadium varied very little. Technological limitations prevented the examination of element levels in any one annulation.

Research in selenium isotopes has been gaining interest as new contaminated sites are identified around the world. Selenium is an emerging contaminant, as it is increasingly being released through anthropogenic activities. It is an element with a very narrow range between nutrient requirement and toxic concentrations. Increased concentrations in the environment are a cause for concern. Selenium can be made less toxic in a system through reduction. Currently, investigations into fractionation caused by the reduction of Se by Fe and Fe minerals are limited. This thesis describes a batch study conducted using granular iron to treat Se(VI) in CaCO3 saturated water, under anaerobic conditions. The amount of Se(VI) in solution decreased to 14.5% of the initial concentration within three days. No quantifiable Se(IV) was found in solution. Analysis of the solid phase showed Se(IV), ferric selenite, FeSe, and Se(0) on the GI. The mass of Se0 on the GI increased over time. Iron selenide compounds became more prevalent after two days had elapsed. Effective fractionations of 4.3??? for 82/76Se and 3.0??? for 82/78Se were observed for this reaction. These effective fractionations are lower than fractionations observed in other experiments for reduction in solution. This discrepancy may be due to the reduction of Se(IV) occurring after adsorbing onto the solid phase, rather than reduction taking place only in solution.

This study used LA-ICP-MS on a documented sample of modern teeth to sample from a continuous line across the cementum increments thus creating a temporal line graph of the elemental composition against distance. The knowledge of cementum was extended through (1) a more complete elemental composition analysis and (2) the relation of element distribution to the ultrastructure structure throughout the life of a tooth. This study was exploratory and demonstrated that lead, zinc, mercury, and barium follow the same general line of changes, and most likely represent changes in health and exposure to these metals in the general environment. Copper, manganese and vanadium varied very little. Technological limitations prevented the examination of element levels in any one annulation.

The advantage of one-bead-one-compound combinatorial libraries is that hundreds of thousands to millions of compounds can be rapidly synthesized and screened simultaneously. The beads supporting the compounds of interest are then isolated and analyzed to decipher the structure of the desired compound. Many methods are currently used to allow deconvolution of the compound on the individual beads. Herein is described a novel method to encode TentaGel beads using absorption of different ratios of lanthanide ions. The encoding process is completed in parallel with the synthesis of the library of compounds. Once the desired beads are identified, the lanthanide ions can be released from the bead and analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).

Submitted by ANA MARTA CAVINATO MARCHINI ROLISOLA (anamartarolisola@hotmail.com) on 2018-06-21T22:43:46Z No. of bitstreams: 1 Ana Marta C M Rolisola_Tese de Doutorado.pdf: 4492180 bytes, checksum: d1fdb4a15ef3fdf8d398b1f8be14c005 (MD5) / Rejected by Ana Paula Santulo Custódio de Medeiros null (asantulo@rc.unesp.br), reason: - Falta o número do processo FAPESP nos agradecimentos: se você recebeu financiamento da FAPESP, ela exige que nos agradecimentos apareça o número do processo. on 2018-06-22T17:15:12Z (GMT) / Submitted by ANA MARTA CAVINATO MARCHINI ROLISOLA (anamartarolisola@hotmail.com) on 2018-06-23T14:11:42Z No. of bitstreams: 1 Ana Marta C M Rolisola_Tese de Doutorado.pdf: 4493139 bytes, checksum: 2980a550f843988e0a8bd31a8ee9ab8d (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-06-25T13:41:05Z (GMT) No. of bitstreams: 1 rolisola_amcm_dr_rcla.pdf: 4377095 bytes, checksum: da8491d59c9f3875c68e364b6648d0cf (MD5) / Made available in DSpace on 2018-06-25T13:41:05Z (GMT). No. of bitstreams: 1 rolisola_amcm_dr_rcla.pdf: 4377095 bytes, checksum: da8491d59c9f3875c68e364b6648d0cf (MD5) Previous issue date: 2018-05-02 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Atualmente, cerca de 18 compostos são utilizados como biocidas de reforço (metálicos) em tintas anti-incrustantes, como por exemplo Piritionato de Zinco (Zn(PT)2), Zineb e Ziram. É relevante o desenvolvimento de um método analítico para determinação das concentrações ambientais de biocidas metálicos. O presente estudo teve como objetivos i)desenvolver uma metodologia de extração em fase sólida (SPE) e cromatografia líquida de alta eficiência acoplada (HPLC) ao espectrômetro de massas com plasma acoplado indutivamente (ICP-MS) para determinação de Zn(PT)2, Zineb e Ziram e ii) quantificar, in lab, a fração lábil total do Piritionato de Zinco, Zineb e Ziram e in situ, a fração lábil total do zinco, utilizando a técnica de difusão em filmes finos por gradiente de concentração (DGT) em solução padrão e água estuarina, respectivamente. Na técnica de SPE foi utilizado o sorbente de sílica funcionalizado com fenil apresentando excelente retenção para Zn(PT)2, Zineb e Ziram (94 ± 0,1%, 85 ± 0,04% e 93 ± 0,1%, respectivamente) e recuperações entre 85% e 110%. Na determinação dos biocidas de zinco utilizando o acoplamento HPLC-VGroove-ICP-MS com diluição pós coluna cromatográfica, a fase móvel composta por metanol e 0,006 mol L-1 de acetato de amônio (50:50, v v-1) apresentou o melhor desempenho na separação do Zn(PT)2, Zineb, Ziram. A curva analítica obtida para o Zn(PT)2 apresentou coeficiente de correlação, LD e LQ satisfatórios para os isótopos 64Zn (0,98, 0,575 mg L-1, 1,916 mg L-1), 66Zn(0,99, 0,480 mg L-1 , 1,600 mg L-1), 68Zn(0,98, 0,602 mg L-1, 2,007 mg L-1). Na técnica DGT foi utilizado o agente ligante resina Chelex® 100 para avaliar a labilidade do Zn(PT)2, Zineb e Ziram em água estuarina. Os resultados demonstraram que a fração lábil total do Zn ficou em torno de 100% para o Zineb (111%) e Ziram (109%), ou seja, estes biocidas formaram espécies totalmente lábeis na amostra de água estuarina e para Zn(PT)2 foi de 75% indicando espécies parcialmente lábeis. Os resultados obtidos na técnica SPE, no acoplamento HPLC-VGroove-ICP-MS e DGT demonstraram que os métodos apresentam desempenho satisfatório para a determinação de Piritionato de Zinco, Zineb e Ziram. / About 18 compounds are used as booster biocides (metal) in antifouling paints such as Zinc Pyrithione (Zn(PT)2), Zineb and Ziram. It is important to develop an analytical method for determining of the environmental concentrations of zinc biocides. The present study had as objectives i) to develop a solid phase extraction (SPE) and high performance liquid chromatography (HPLC) coupled to the inductively coupled plasma mass spectrometer (ICP-MS) for the determination of Zn(PT)2, Zineb and Ziram and ii) quantify in lab the total labile fraction of Zn(PT)2, Zineb and Ziram and in situ the total labile fraction of zinc using the diffusive gradient in thin films (DGT) technique in standard solution and estuarine water, respectively. In the SPE technique, the silica sorbent functionalized with phenyl presented excellent retention for Zn(PT)2, Zineb and Ziram (94 ± 0.1%, 85 ± 0.04% and 93 ± 0.1%, respectively) and recoveries between 85% and 110%. In the determination of zinc using the HPLC-VGroove-ICP-MS coupling with post-column chromatographic dilution, the mobile phase composed of methanol and 0.006 mol L-1 of ammonium acetate (50:50, v v-1) of presented the best performance in the separation of Zn(PT)2, Zineb and Ziram. The analytical curve obtained for Zn(PT)2 presented satisfactory correlation coefficient, LD and LQ for the isotopes 64Zn (0.98, 0.575 mg L -1, 1.916 mg L-1), 66Zn (0.99, 0.480 mg L-1, 1.600 mg L-1), 68Zn (0.98, 0.602 mg L-1, 2.007 mg L-1). In the DGT technique, the Chelex® 100 resin binder was used to evaluate the lability of the zinc biocides Zn(PT)2, Zineb and Ziram in estuarine water. The results showed that the total labile fraction of Zn was around 100% for Zineb (111%) and Ziram (109%), that is, these biocides formed totally labile species in the estuarine water sample and for Zn(PT)2 was 75% indicating partially labile species. The results obtained in the SPE technique in the HPLC-VGroove-ICP-MS coupling and DGT demonstrated that the methods present satisfactory performance for the determination of Zn(PT)2, Zineb and Ziram. / CNPq: 164326/2015. / FAPESP: 2015/03397-4.

Chumbo (Pb) é um elemento tóxico ao qual estão associadas diversas doenças que afligem o ser humano. Dessa forma, o desenvolvimento de novas metodologias para a determinação de Pb no sangue traz uma importante contribuição na monitoração humana exposta a este metal. No presente estudo, é apresentado uma metodologia nova para determinação de Pb utilizando-se a técnica fingerstick com filtro de papel em conjunto com a espectrometria de massas de alta resolução em fonte de plasma indutivo (HR/ICP/MS). Os resultados encontrados mostraram-se robustos para uma digestão total de cerca de 0,1 g de sangue, em valores de referência, e níveis de chumbo inferiores a 5 μgdL-1. O presente método é pouco intrusivo permitindo a coleta e transporte das amostras à longa distância sem perda de integridade e/ou estabilidade. Dessa forma traz uma importante contribuição para o monitoramento da exposição do metal principalmente no atendimento às comunidades distantes. / Lead (Pb) is a toxic element to which several diseases affecting human beings are associated. Therefore, the development of new methodologies for the Pb determination in blood represents an important contribution to monitor human exposition to this metal. In the present study, a new methodology for Pb determination is presented using fingerstick techniques for sample collection and lead detection by using a high resolution inductively coupled plasma mass spectrometry technique. The results are robust for total digestion of 0.1 g of deposited blood and lead levels below to 5 μgdL-1. This method is less intrusive in comparison with the traditional ones. It allows the collection and transport of samples over long distances without loss of integrity and / or stability. Therefore, it brings an important contribution for monitoring the exposure of this metal mainly in the attendance to remote communities.