Microwave-induced plasma emission

Lobinski et al. [72] optimized conditions for the comprehensive speciation of organotin compounds in soils and sediments. They used capillary gas chromatography coupled to helium microwave induced plasma emission spectrometry to determine mono-, di-, tri- and some tetraalkylated tin compounds. Ionic organotin compounds were extracted with pentane from the sample as the organotin-diethyldithiocarbamate complexes then converted to their pentabromo derivatives prior to gas chromatography. The absolute detection limit was 0.5pg as tin equivalent to 10-30pg kg-1. 

River and marine sediments, soils Bu3Sn BujSn BuSn Capillary glc-helium microwave induced plasma emission spectrometric detection 0.0001-0.0003 [72] ... 

Bulska, E., Emteborg, H., Baxter, D.C., Freeh, W., Elligsen, D. and Thomassen, Y. (1992) Speciation of mercury in human whole blood by capillary gas chromatography with a microwave-induced plasma emission detector system following complexometric extraction and butylation. Analyst, 117, 657-663. 

Lobinski, R., Dirkx, W.M.R., Ceulemans, M. and Adams, F.C. (1992) Optimization of comprehensive speciation of organotin compounds in environmental samples by capillary gas chromatography helium microwave-induced plasma emission spectrometry. Anal. Chem., 64, 159-165. 

Chiba et al. [749] used atmospheric pressure helium microwave induced plasma emission spectrometry with the cold vapour generation technique combined with gas chromatography for the determination of methylmercuiy chloride, ethylmercury chloride and dimethylmercury in sea water following a 500-fold preconcentration using a benzene- cysteine extraction technique. 

Because of its low specificity and sensitivity flame ionisation detection (FID) can only be used in the analysis of standard substances [37]. The same limited application is envisaged for the method with the microwave-induced plasma emission detector, which is not sensitive enough for environmental samples [2]. 

Nojiri, Y., Otsuki, A. and Fuwa, K. (1986) Determination of sub-nanogram-per-liter levels of mercury in lake water with atmospheric pressure helium microwave induced plasma emission spectrometry. Anal. Chem., 58, 544-547. 

All major modern atomic absorption and emission techniques and instrumentation are covered. Appendices with FAAS and GFAAS conditions have been added, and a new appendix with up-to-date hmits of detection for all the atomic spectroscopic techniques is included. Chemical speciation using hyphenated chromatographic-atomic emission spectroscopy is described as is a novel microwave induced plasma emission instrument for particle characterization. 

A number of very useful and practical element selective detectors are covered, as these have already been interfaced with both HPLC and/or FIA for trace metal analysis and spe-ciation. Some approaches to metal speciation discussed here include HPLC-inductively coupled plasma emission, HPLC-direct current plasma emission, and HPLC-microwave induced plasma emission spectroscopy. Most of the remaining detection devices and approaches covered utilize light as part of the overall detection process. Usually, a distinct derivative of the starting analyte is generated, and that new derivative is then detected in a variety of ways. These include HPLC-photoionization detection, HPLC-photoelectro-chemical detection, HPLC-photoconductivity detection, and HPLC-photolysis-electrochemical detection. Mechanisms, instrumentation, details of interfacing with HPLC, detector operations, as well as specific applications for each HPLC-detector case are presented and discussed. Finally, some suggestions are provided for possible future developments and advances in detection methods and instrumentation for both HPLC and FIA. 

Interfacing of Gas Chromatography with Microwave-Induced Plasma Emission Detection (GC-MIP)... 

The first GC-microwave-induced plasma emission system was reported in 1965 [23]. During the past two decades GC-plasma emission systems have gained in popularity and have been used for the identification and quantification of mercury, lead, tin, selenium, and arsenic compounds [13]. The most frequently used plasma source is the microwave-induced plasma operated either at reduced pressure or at atmospheric pressure with helium or argon as the plasma gases at powers of 100 to 200 W The Beenakker cylindrical resonance cavity introduced in 1976 [24], and since then modified to achieve better detection limits, is most frequently used in the GC-microwave-induced plasma emission systems that are easily adaptable to capillary GC operation. These microwave-induced plasma detectors respond to non-metals (H, D, B, C, N, O, F, Si, F S, Cl, As, Se, Br, I) and metals, with absolute detection limits in... 

Common gas chromatographic detectors that are not element- or metal-specific, atomic absorption and atomic emission detectors that are element-specific, and mass spectrometric detectors have all been used with the hydride systems. Flame atomic absorption and emission spectrometers do not have sufficiently low detection limits to be useful for trace element work. Atomic fluorescence [37] and molecular flame emission [38-40] were used by a few investigators only. The most frequently employed detectors are based on microwave-induced plasma emission, helium glow discharges, and quartz tube atomizers with atomic absorption spectrometers. A review of such systems as applied to the determination of arsenic, associated with an extensive bibliography, is available in the literature [36]. In addition, a continuous hydride generation system was coupled to a direct-current plasma emission spectrometer for the determination of arsenite, arsenate, and total arsenic in water and tuna fish samples [41]. 

Organotin compounds Capillary column Helium microwave induced plasma emission spectrometry... 

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