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Determination of Ca and P in foods and B, Si, P and S in steels by dynamic reaction cell inductively coupled plasma mass spectrometry

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Ultrasonic slurry sampling electrothermal vaporization dynamic reaction cellTM inductively coupled plasma mass spectrometry (USS-ETV-DRC-ICP-MS) has been applied to the determination of As and Se in soil and sediment samples. The influences of instrument operating conditions and slurry preparation on the ion signals were reported. Ascorbic acid and Pd were used as the modifiers to enhance the ion signals. The background ions at the selenium masses were reduced in intensity significantly by using 1.5 ml min-1 H2 as reaction cell gas in the DRC while a q value of 0.65 was used. Since the sensitivities of As and Se in slurry solution and aqueous solution were quite different, standard addition method was used for the determination of As and Se in these samples. This method has been applied to the determination of As and Se in NIST SRM 2711 Montana soil and SRM 2709 San Joaquin soil reference materials and NRCC BCSS-1 marine sediment reference sample. The analysis results of the reference materials were agreed with the certified values. The method detection limits estimated from standard addition curves were about 0.046-0.082 and 0.019-0.024 mg g-1 for As and Se, respectively, in original soil and sediment samples.

No description available.

No description available.

Accelerator Mass Spectrometry (AMS) studies of rare isotopes with abundant isobars that form negative ions often require the use of large accelerators to achieve high sensitivity measurements. The Isobar Separator for Anions (ISA) is a radiofrequency quadrupole (RFQ) reaction cell system that provides selective isobar suppression for many of these isotopes in the low energy system, prior to injection into an accelerator. The ISA can then facilitate the measurement of these ions using smaller accelerators. A commercial version from Isobarex Corp. was installed in a separate low energy injection line of the 3 MV accelerator system at the A. E. Lalonde AMS Laboratory in the University of Ottawa and was tested using the measurement of 36Cl, suppressing its stable isobar 36S. The ISA includes a DC deceleration region, a combined cooling and reaction cell, and a DC acceleration region. The deceleration region reduces the beam energy from the ion source (20-35 keV) to a level that chemical reactions can occur, scattering is minimized, and that the reaction cell can accept and contain. RFQ segments along the length of the cell create a potential well, which limits the divergence of the traversing ions. DC offset voltages on these RFQ segments maintain a controlled ion velocity through the cell. Helium was used as a cooling gas to further decelerate the ions, facilitating charge exchange between 36S and a reaction gas. Helium provided the highest transmission of 30-80% for chlorine anions. The reaction gas NO2 was chosen to preferentially react with sulfur. Over seven orders of magnitude reduction of sulfur to chlorine was observed. After exiting the cell, the beam is reaccelerated prior to injection into the tandem accelerator for AMS analysis. Using 36Cl reference materials, it was determined that linear transmission results could be obtained for a 36Cl/Cl ratio ranging from 10−11 to 10−15. The measurements were stable over more than 24 hours of continuous measurement. A blank level on the order of 10−15 was observed. The ISA was used to measure unknown 36Cl /Cl ratio groundwater samples and the results are compared to external AMS measurements.

Os minerais são de extrema importância no metabolismo geral e no desempenho produtivo e reprodutivo dos bovinos. Atualmente, no Brasil, existem poucos estudos sobre o diagnóstico de deficiências minerais em bovinos, através de análise de macroelementos e elementos traço em fluidos biológicos. A maior parte das informações disponíveis limitam-se ao diagnóstico clínico de deficiências isoladas e à análise de elementos nas pastagens e no solo, que podem sugerir deficiências sub clínicas de alguns minerais, mas apresentam várias limitações e interferências. O objetivo deste trabalho foi desenvolver um método de análise simples, com introdução direta da amostra, utilizando a técnica de q-ICP-MS e DRC-ICP-MS, para determinação de Ca, Cu, Fe, Mg, Zn, I, Mo, As, Se, Ni, Co, Ba, Cs, Mn e Pb em sêmen bovino. Para realização das análises, foi utilizada calibração em meio aquoso e as amostras foram diluídas na proporção 1:50 em solução contendo 0,01% v/v Triton® X-100 e 0,5% v/v de ácido nítrico. Também foram avaliadas a calibração por ajuste de matriz e a análise das amostras após digestão por microondas, para confirmação dos resultados obtidos por introdução direta e calibração em meio aquoso. O DRC foi essencial para determinação de níquel. O gás de reação utilizado foi H2 e os parâmetros RPq e vazão do gás foram estudados para otimização do método. Os limites de detecção para determinação de 44Ca, 63Cu, 57Fe, 24Mg, 64Zn, 127I, 98Mo, 75As, 82Se, 59Co, 138Ba, 133Cs, 55Mn e 208Pb foram: 0,262; 0,003; 0,168; 0,004; 0,004; 0,026; 0,007; 0,007; 0,033; 0,002; 0,005; 0,002; 0,003; 0,002 µg L-1 respectivamente, e para determinação de 60Ni por DRC-ICP-MS o LD foi 0,020 µgL-1. O método desenvolvido foi aplicado para determinação de 15 elementos em amostras de sêmen de bovinos de diferentes raças usadas em programas de reprodução e inseminação artificial. / The minerals are of extreme importance in the general metabolism and in the productive and reproductive performance of the bovines. Nowadays, in Brazil, few studies exist on the diagnosis of mineral deficiencies in bovine, through macroelementos analysis and trace elements in biological fluids. Most of the available information is limited to the clinical diagnosis of isolated deficiencies and the analysis of elements in the pastures and in the soil, that can suggest sub clinical deficiencies of some minerals, but present several limitations and interferences. The objective of this work was to develop a method of simple analysis, with direct introduction of the sample, using the technique of q-ICP-MS and DRC-ICP-MS, for determination of Ca, Cu, Fe, Mg, Zn, I, Mo, As, Se, Ni, Co, Ba, Cs, Mn and Pb in bovine semen. Aqueous medium calibration was used in the analysis and the samples were diluted in the proportion 1:50 in solution containing 0,01% v/v Triton® X-100 and 0,5% v/v of nitric acid. They were also evaluated the matrix matching and the analysis of samples after digestion for microwave, for confirmation of the results obtained by direct introduction and calibration in aqueous medium. DRC went essential for nickel determination. The reaction gas used it was H2 and the parameters RPq and gas flow rate were studied for optimization of the method. The detection limits for determination of 44Ca, 63Cu, 57Fe, 24Mg, 64Zn, 127I, 98Mo, 75As, 82Se, 59Co, 138Ba, 133Cs, 55Mn and 208Pb were: 0,262; 0,003; 0,168; 0,004; 0,004; 0,026; 0,007; 0,007; 0,033; 0,002; 0,005; 0,002; 0,003; 0,002 µg L-1 respectively, and for determination of 60Ni for DRC-ICP-MS the LOD was 0,020 µgL-1. The developed method was applied for determination of 15 elements in bovine semen samples of different breed used in reproduction programs and artificial insemination.

Os minerais são de extrema importância no metabolismo geral e no desempenho produtivo e reprodutivo dos bovinos. Atualmente, no Brasil, existem poucos estudos sobre o diagnóstico de deficiências minerais em bovinos, através de análise de macroelementos e elementos traço em fluidos biológicos. A maior parte das informações disponíveis limitam-se ao diagnóstico clínico de deficiências isoladas e à análise de elementos nas pastagens e no solo, que podem sugerir deficiências sub clínicas de alguns minerais, mas apresentam várias limitações e interferências. O objetivo deste trabalho foi desenvolver um método de análise simples, com introdução direta da amostra, utilizando a técnica de q-ICP-MS e DRC-ICP-MS, para determinação de Ca, Cu, Fe, Mg, Zn, I, Mo, As, Se, Ni, Co, Ba, Cs, Mn e Pb em sêmen bovino. Para realização das análises, foi utilizada calibração em meio aquoso e as amostras foram diluídas na proporção 1:50 em solução contendo 0,01% v/v Triton® X-100 e 0,5% v/v de ácido nítrico. Também foram avaliadas a calibração por ajuste de matriz e a análise das amostras após digestão por microondas, para confirmação dos resultados obtidos por introdução direta e calibração em meio aquoso. O DRC foi essencial para determinação de níquel. O gás de reação utilizado foi H2 e os parâmetros RPq e vazão do gás foram estudados para otimização do método. Os limites de detecção para determinação de 44Ca, 63Cu, 57Fe, 24Mg, 64Zn, 127I, 98Mo, 75As, 82Se, 59Co, 138Ba, 133Cs, 55Mn e 208Pb foram: 0,262; 0,003; 0,168; 0,004; 0,004; 0,026; 0,007; 0,007; 0,033; 0,002; 0,005; 0,002; 0,003; 0,002 µg L-1 respectivamente, e para determinação de 60Ni por DRC-ICP-MS o LD foi 0,020 µgL-1. O método desenvolvido foi aplicado para determinação de 15 elementos em amostras de sêmen de bovinos de diferentes raças usadas em programas de reprodução e inseminação artificial. / The minerals are of extreme importance in the general metabolism and in the productive and reproductive performance of the bovines. Nowadays, in Brazil, few studies exist on the diagnosis of mineral deficiencies in bovine, through macroelementos analysis and trace elements in biological fluids. Most of the available information is limited to the clinical diagnosis of isolated deficiencies and the analysis of elements in the pastures and in the soil, that can suggest sub clinical deficiencies of some minerals, but present several limitations and interferences. The objective of this work was to develop a method of simple analysis, with direct introduction of the sample, using the technique of q-ICP-MS and DRC-ICP-MS, for determination of Ca, Cu, Fe, Mg, Zn, I, Mo, As, Se, Ni, Co, Ba, Cs, Mn and Pb in bovine semen. Aqueous medium calibration was used in the analysis and the samples were diluted in the proportion 1:50 in solution containing 0,01% v/v Triton® X-100 and 0,5% v/v of nitric acid. They were also evaluated the matrix matching and the analysis of samples after digestion for microwave, for confirmation of the results obtained by direct introduction and calibration in aqueous medium. DRC went essential for nickel determination. The reaction gas used it was H2 and the parameters RPq and gas flow rate were studied for optimization of the method. The detection limits for determination of 44Ca, 63Cu, 57Fe, 24Mg, 64Zn, 127I, 98Mo, 75As, 82Se, 59Co, 138Ba, 133Cs, 55Mn and 208Pb were: 0,262; 0,003; 0,168; 0,004; 0,004; 0,026; 0,007; 0,007; 0,033; 0,002; 0,005; 0,002; 0,003; 0,002 µg L-1 respectively, and for determination of 60Ni for DRC-ICP-MS the LOD was 0,020 µgL-1. The developed method was applied for determination of 15 elements in bovine semen samples of different breed used in reproduction programs and artificial insemination.