Atomic absorption spectrometry Zeeman background correction

Many of the published methods for the determination of metals in seawater are concerned with the determination of a single element. Single-element methods are discussed firstly in Sects. 5.2-5.73. However, much of the published work is concerned not only with the determination of a single element but with the determination of groups of elements (Sect. 5.74). This is particularly so in the case of techniques such as graphite furnace atomic absorption spectrometry, Zeeman background-corrected atomic absorption spectrometry, and inductively coupled plasma spectrometry. This also applies to other techniques, such as voltammetry, polarography, neutron activation analysis, X-ray fluroescence spectroscopy, and isotope dilution techniques. 

Ellen G, Van Loon JW. 1990. Determination of cadmium and lead in foods by graphite furnace atomic absorption spectrometry with Zeeman background correction Test with certified reference materials. Food Addit Contam 7 265-273. 

Chapters 5 and 6 discuss the application of new techniques such as atomic absorption spectrometry with and without graphite furnace and Zeeman background correction, inductively coupled plasma mass spectrometry, X-ray fluo-... 

Graphite furnace atomic absorption spectrometry with the L vov platform and Zeeman background correction has been applied to the determination of down to 0.02 xg/l manganese in seawater [452]. 

Zong, Y. Y., Parsons, P. J., and Slavin, W. (1998). Background correction errors for lead in the presence of phosphate with Zeeman graphite furnace atomic absorption spectrometry. Spectrochimica Acta B 53 1031-1039. 

Guillard 0, Tiphaneau K, Reiss D, et al. 1984. Improved determination of aluminum in serum by electrothermal atomic absorption spectrometry and zeeman background correction. Anal Lett 17 1593-1605. 

Dube P. 1988. Determination of chromium in human urine by graphite furnace atomic absorption spectrometry with Zeeman-effect background correction. Analyst 113 917-921. 

For the homogeneity and stability studies, the trace element contents (Cd, Cr, Cu, Ni, Pb and Zn) were determined by flame atomic absorption spectrometry (FAAS) or electrothermal atomic absorption spectrometry with Zeeman background correction (ZETAAS), strictly following the sequential extraction procedure. Differences between the within-bottle and between-bottle CVs observed for the step 2 were considered to be rather an analytical artefact than an indication of inhomogeneity which would have been reflected in the spread of results submitted in the certification. The material is then considered to be homogeneous for the stated level of intake (1 g). 

For the homogeneity studies, the extractants (0.05 mol L EDTA, 0.43 mol L" acetic acid and 0.005 mol L DTPA) were prepared as laid out in the certification reports [15, 17], The trace element contents (Cd, Cr, Cu, Ni, Pb and Zn) in the extracts were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) for the CRMs 483/484, flame atomic absorption spectrometry (FAAS) or electrothermal atomic absorption spectrometry with Zeeman background correction (ZETAAS) for the CRM 600. In the case of the CRM 483, little analytical difficulty was experienced as illustrated by the good agreement obtained between the within-bottle and between-bottle CVs for the CRM 484, lower extractable contents, closer to the detection limits and consequent poorer analytical precision was observed in particular for Cr (EDTA extractable contents), Cd and Pb (acetic acid extractable contents). No particular difficulties were experienced for the CRM 600. On the basis of these results, the materials were considered to be homogeneous at a level of 5 g for EDTA- and acetic acid-extractable contents and 10 g for DTPA-extractable contents (as specified in the extraction protocols). 

Lewis SA, Hardison NW, Veillon C. 1986. Comparison of isotope dilution mass spectrometry and graphite furnace atomic absorption spectrometry with Zeeman background correction for determination of plasma selenium. Anal Chem 58 1272-1273. 

Analytical Methods and Speclatlon Electrothermal atomic absorption spectrophotometry (ETAAS), differential pulse adsorption voltammetry (DPAV), isotope-dilution mass spectrometry (ID-MS), and inductively coupled plasma mass spectrometry (ICP-MS) furnish the requisite sensitivity for measurements of nickel concentrations in biological, technical and environmental samples (Aggarwal et al. 1989, Case et al. 2001, Stoeppler and Ostapczuk 1992, Templeton 1994, Todorovska et al. 2002, Vaughan and Templeton 1990, Welz and Sperling 1999). The detection limits for nickel determinations by ETAAS analysis with Zeeman background correction are approximately 0.45 jg for urine,... 

The Zeeman effect arises from the interaction of an external magnetic field ivith the magnetic moment of the emitting (direct Zeeman effect) or absorbing (inverse Zeeman effect) atom, resulting in split emission lines. This phenomenon has made a significant contribution to nonatomic background correction in atomic absorption spectrometry, especially in electrothermal AAS ivhere more serious nonatomic, nonspecific absorptions occur. 

Nixon. D.E., Moyer, T.P., Squillace, D.P. and McCarthy, J.T. (1989). Determination of serum nickel by graphite furnace atomic absorption spectrometry with Zeeman-effect background correction Values in a normal population and a population undergoing dialysis. Analyst 114,1671-1674. 

Radziuk B, Rodel G, Stenz H, Becker-Ross H, Florek S (1995) Spectrometer system for simultaneous multielement electrothermal atomic absorption spectrometry using line sources and Zeeman-effect background correction. J Anal At Spectrom 10 127—136 Rao CRM, Reddi GS (2000) Platinum group metals (PGM) occurrence, use and recent trends in their determination. Trends Anal Chem 19 565-586 Rauch S, Lu M, Morrison GM (2001) Heterogeneity of platinum group metals in airborne particles. Env Sci Technol 35 595-599... 

Direct measurements of several trace metals by electrothermal atomic absorption spectrometry (ETAAS) have been reported. In general, sensitivities are inadequate for open-ocean waters, though in more metal-enriched environments (e.g., coastal waters and sediment pore waters) such analysis is possible careful corrections for the large and complex salt effects are necessary. The interferences can be minimized by the use of appropriate chemical modifiers, platforms in the graphite tubes, and sophisticated background correction schemes such as Zeeman. 

AAS is the most widely used analytical technique for the determination of lead in biological materials [57,58], The majority of AAS methods employ the electrothermal atomic absorption spectrometry (ETAAS) technique, using either Zeeman background correction or deuterium background correction for the determination of lead in biological fluids [55,59-65], Urine is less often employed as an indicator of exposure however, similar problems associated with AAS determination of lead exist for blood as well as urine (1) incomplete atomization (2) volatile lead salts (3) spectral interferences (4) buildup of carbonaceous residue reducing sensitivity and precision. These analytical problems are eliminated by optimal sample preparation, e,g., dilution, addition of matrix modifiers, deproteinization, and background correction and calibration by matrix-matched standards [66],... 

Kimberly. M. Determination of Cadmium in Urine by Graphite Furnace Atomic Absorption Spectrometry with Zeeman Background Correction." Centers for Disease Control. Atlanta, Georgia, unpublished, update 1990. 

J.Y. Cabon and A.L. Bihan. Direct determination of zinc in seawater using electrothermal atomic absorption spectrometry with Zeeman-effect background correction effects of chemical and spectral interferences. Journal of Analytical Atomic Spectrometry 9 477-481,1994. 

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