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[en] The main features of flow injection analysis (FIA) as contribution to the inductively coupled plasma (Icp) spectrometry are described. A systematic review of researches using the combined FIA-Icp and the benefits of this association are presented. Flow systems were proposed to perform on-line Icp solution management for multielemental determination by atomic emission spectrometry (Icp-AES) or mass spectrometry. The inclusion of on-line ion exchangers in flow systems for matrix separation and/or analyte preconcentration are presented. Together with those applications the new advent of instruments with facilities for multielement detection on flow injection signals are described. (author). 75 refs., 19 figs
[en] Complete text of publication follows. This presentation will focus on new tools that are being developed for the practice of mass and optical spectrometry. For use in mass spectrometry, novel spectrometers and detectors will be featured, while for optical spectroscopy, a new emission source applicable to environmental analysis will be evaluated. One mass spectrometer that will be described is intended to accept two sources at the same time, in a truly simultaneous fashion. Another enables an entire mass range to be detected at once, so efficiency, speed, and precision are improved, while spectral skew is avoided. The emission source to be described is intended for field applications. It offers detection limits that rival those from the ICP, but requires only a 60Wdc power supply, no flowing gases, and can use a relatively simple monochromator.
[en] In recent years, knowledge of the different chemical forms of the elements has gained increasing importance. There has been significant progress in methods that hyphenate chromatographic separations with atomic spectrometry. These hyphenated methods can provide the most complete information on the species distribution and even structure. However, they can be lengthy, relatively costly and difficult to bring to the routine. On the other hand, it is important to remember that chromatographic techniques represent only a minor part of the separation procedures available and, in certain cases, the application of basic chemistry to sample treatments can give quantitative information about specific chemical forms. In this sense, non-chromatographic procedures can provide methods that offer sufficient information on the elemental speciation for a series of situations. Moreover, these non-chromatographic strategies can be less time consuming, more cost effective and available, and present competitive limits of detection. Thus, non-chromatographic speciation analysis continues to be a promising research area and has been applied to the development of several methodologies that facilitate this type of analytical approach. In view of their importance, the present work overviews and discusses different non-chromatographic methods as alternatives for the speciation analysis of clinical, environmental and food samples using atomic spectrometry for detection.
[en] Complete text of publication follows. A novel approach for the direct analysis of laser aerosols ablated and transported in ambient air using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry will be reported. Aerosols were generated under ambient air passed through a gas exchanger and finally introduced into an ICP-MS. The sensitivity obtained when using air in comparison to Ar was not found to be significantly different for the ablation of a synthetic glass SRM NIST 610 using an ArF excimer laser operating at 193 nm. However an increase in sensitivity with approximately a factor of 7 was measured when using air compared to Ar for the ablation of a pure copper sample. To date helium has been reported to be a more suitable cell gas than argon owing to the reduced sample deposition on the sample surface, moreover due to a more efficient aerosol transport into the plasma (S. M. Eggins, L. P. J. Kinsley, J. M. G. Shelley, Appl. Surf. Sci., 129 (1998) 278-286.). However, investigations on the ion distribution of laser generated aerosols within the ICP have shown that the use of helium contributes to loss of ions owing to diffusion in the plasma in contrast to argon (Z. Wang, B. Hattendorf, D. Guenther, J. Anal. At. Spectrom., 21 (2006) 1143-1151.). Experiments showed that combining the benefits of helium as cell gas and argon only in the ICP might further improve the sensitivity. This work is financially supported by the Swiss National Science Foundation and ETH Zurich. Sumitomo Seika Chemicals Co., Ltd., Japan is gratefully acknowledged for providing the gas exchange unit.
[en] The most sensitive technologies for ultra-low-level analyses of long-lived radionuclides have been accelerator mass spectrometry and inductively coupled plasma mass spectrometry, reaching detection limits about 1 nBq/g. Together with underground operation of large volume HPGe detectors they have had great impact on underground physics experiments, approaching new frontiers in radioanalytics - a single atom counting. (author)
[en] Complete text of publication follows. The scope of research in the field of elemental speciation has considerably evolved during the last decade. The analysis of specific metal-containing contaminants reached the maturity and has given way to the development of analytical methods to describe interactions of metals with biomolecules which are constituents of the genome, proteome, metabolome and other -omes in a cell, tissue or organism. The entirety of metal-biomolecule species has been termed the 'metallome' which gave rise to an emerging discipline: metallomics. Advances of trace element analysis in life sciences resulted in the proliferation of new terms related to the description of metal-interactions with biomolecules, such as, e.g. ionome, metalloproteome, metallogenome, metallometabolome, heteroatom-tagged proteome, single element proteomes (e.g., selenoproteome) and the corresponding -omics. The analytical chemistry challenges in the area metallomics include the detection, quantification, identification and characterization of complexes of metals (metalloids) at trace levels in an environment rich in biomolecules often having similar physicochemical properties. In the past, the only way to access to this information was modelling using stability constants. Today, hyphenated techniques based on the coupling of a high resolution separation technique with sensitive elemental (ICP MS) and molecular (ES MS/MS) mass spectrometry offer the possibility of high-throughput acquisition of metallomics information in many biological systems. The lecture discusses advances in analytical techniques in the field of metallomics. Particular attention will be to developments in multidimensional nanoHPLC with the parallel ICP MS and ESI MS detection and the sensitive spotting of heteroelement-containing proteins in 2D gels, accompanied by advances in MALDI TOF MS. Potential for medical research (e.g., characterization for selenoproteins as new biomarkers of clinical utility) and for nutrition research (e.g., targets of metal binding for both nutritive and toxic elements) will be discussed.
[en] Complete text of publication follows. This topic involves the determination of Pt and Pd content of precious metal-bearing rocks (from the Sudbury magmatic complex) by inductively coupled plasma spectrometric methods. Altogether 9 samples were available for the comparison of recoveries by lead fire assay and decomposition by aqua regia. The standard analytical method for the determination of platinum group elements in the Laboratory of GIH is ICP-OES and ICP-MS analysis after aqua regia decomposition. The matrix was very heavy, up to 35% in Cu; 30% in Fe and 3% in Ni. A JY ULTIMA 2C ICP-OES instrument was used for the determination of Pt and Pd content from the aqua regia solution. Although this instrument has a very good spectral resolution (5 pm), the straight analysis is not easy in a complicated, line-rich matrix. The background positions were changing at most of the samples, therefore graphical evaluation was the best for subtracting the proper background values. Several analytical lines were used for the determination of Pt and Pd. The Pt and Pd contents were also analysed by ICP-MS (Perkin-Elmer ELAN DRC II) on different isotopes. The different Pd isotopes supplied different concentrations indicating that spectral overlaps made the strait analysis very difficult and uncertain. There was a possibility within a bilateral scientific cooperation with the South Vietnam Geological Mapping Division of Analysis and Experiment (Ho Chi Minh City) to complete lead fire assay procedures from these samples. After dissolving the silver prill at the end of the procedure the ICP-OES and the ICP-MS analysis were performed again from the relatively matrix-free solutions. The results of the 2 decompositions were compared.
[en] The author examines the application of NCI (study of negative ions created by chemical ionization and particularly by a reacting negative ion) on a model popular at the present time: the passion fruit. The author stresses that this technique has its limitations and should be considered as auxiliary to electron impact. However, it seems destined for a promising future for the analysis of natural produce
[fr]L'auteur etudie l'application de la NCI (etude des ions negatifs crees par une ionisation chimique et plus particulierement par un ion negatif reactant) sur un modele en vogue a l'heure actuelle: le fruit de la passion. L'auteur souligne que cette technique connait des limites et qu'elle est a considerer comme une technique d'appoint de l'impact electronique. Cependant, elle semble appelee a un avenir prometteur dans le domaine de l'analyse des produits naturels