Atomic absorption spectrometry electrothermal atomizer

The section on Spectroscopy has been retained but with some revisions and expansion. The section includes ultraviolet-visible spectroscopy, fluorescence, infrared and Raman spectroscopy, and X-ray spectrometry. Detection limits are listed for the elements when using flame emission, flame atomic absorption, electrothermal atomic absorption, argon induction coupled plasma, and flame atomic fluorescence. Nuclear magnetic resonance embraces tables for the nuclear properties of the elements, proton chemical shifts and coupling constants, and similar material for carbon-13, boron-11, nitrogen-15, fluorine-19, silicon-19, and phosphoms-31. 

Miscellaneous. Trace analyses have been performed for a variety of other materials. Table 9 Hsts some uses of electrothermal atomic absorption spectrometry (etaas) for determination of trace amounts of elements in a variety of matrices. The appHcations of icp /ms to geological and biological materials include the following (165) ... 

INDIRECT DETERMINATION OF ASCORBIC ACID BY ELECTROTHERMAL ATOMIC ABSORPTION SPECTROMETRY... 

COMPARISON OF MICROWAVE ASSISTED EXTRACTION METHODS FOR THE DETERMINATION OF PLATINUM GROUP ELEMENTS IN SOIL SAMPLES BY ELECTROTHERMAL ATOMIC ABSORPTION SPECTROMETRY AFTER PHASE SEPARATION-EXTRACTION... 

The development of methods using sorbents modified with analytical reagents that enable analytical signal measuring directly on the surface by solid-phase spectrometry, visually or by electrothermic atomic absorption spectroscopy (ETAAS) after elution is now a subject of growing interest. 

Electrothermal vaporization can be used for 5-100 )iL sample solution volumes or for small amounts of some solids. A graphite furnace similar to those used for graphite-furnace atomic absorption spectrometry can be used to vaporize the sample. Other devices including boats, ribbons, rods, and filaments, also can be used. The chosen device is heated in a series of steps to temperatures as high as 3000 K to produce a dry vapor and an aerosol, which are transported into the center of the plasma. A transient signal is produced due to matrix and element-dependent volatilization, so the detection system must be capable of time resolution better than 0.25 s. Concentration detection limits are typically 1-2 orders of magnitude better than those obtained via nebulization. Mass detection limits are typically in the range of tens of pg to ng, with a precision of 10% to 15%. 

Lead in soil slurries Electrothermal atomic absorption spectrometry... 

Tetra-alkyl lead compounds in air Personal monitoring with atomic absorption analysis or electrothermal atomization or X-ray fluorescence spectrometry or on-site colorimetry 9... 

Electrothermal Atomic Absorption Spectrometry of Trace Metals in Biological Fluids... 

The scope of this review Is limited to electrothermal atomic absorption spectrometry, with emphasis upon Its clinical applications. This article Is Intended to supplement the recent treatises on the basic technique which have been written by Aggett and Sprott ( ) > Ingle ( ), Klrkbrlght (34), Price (63), and Woodrlff (83). This resume does not consider various related topics, such as (a) atomic fluorescence or emission spectrometry (b) non-flame atomization devices which employ direct current... 

Inadequate regulation of atomizer temperature Is a major source of Imprecision In electrothermal atomic absorption spectrometry. The programmed heating of electrothermal atomizers can be achieved by five different methods, depending upon the electrical or physical parameters which are monltorled during... 

Micro-pipetting instruments such as the "Eppendorf or "Oxford pipettors with disposable plastic cone tips are customarily employed to dispense the liquid samples into electrothermal atomizers. Sampling problems which are associated with the use of these pipettors are among the troublesome aspects of electrothermal atomic absorption spectrometry (67,75). The plastic cone-tips are frequently contaminated with metals, and they should invariably be cleaned before use by soaking in dilute "ultra pure nitric acid, followed by multiple rinses with demineralized water which has been distilled in a quartz still. 

Aqueous standard solutions are a source of certain difficulties In electrothermal atomic absorption spectrometry of trace metals In biological fluids The viscosities and surface tensions of aqueous standard solutions are substantially less than the viscosities and surface tensions of serum, blood and other proteln-contalnlng fluids These factors Introduce volumetric disparities In pipetting of standard solutions and body fluids, and also cause differences In penetration of these liquids Into porous graphite tubes or rods Preliminary treatment of porous graphite with xylene may help to minimize the differences of liquid penetration (53,67) A more satisfactory solution of this problem Is preparation of standards In aqueous solutions of metal-free dextran (50-60 g/llter), as first proposed by Pekarek et al ( ) for the standardization of serum chromium analyses This practice has been used successfully by the present author for standardization of analyses of serum nickel The standard solutions which are prepared In aqueous dextran resemble serum In regard to viscosity and surface tension Introduction of dextran-contalnlng standard solutions Is an Important contribution to electrothermal atomic absorption analysis of trace metals In body fluids. 

N1 and Zn from a graphite rod were significantly lower than from a tantalum filament, suggesting that these free metal atoms can be liberated by chemical reduction of their respective oxides, rather than by direct thermal dissociation. Findlay et al (19) emphasized the hazards of preatomlzatlon losses of trace met s In electrothermal atomic absorption spectrometry, when the ashing temperature Is permitted to exceed the minimum temperature for vaporization of the analyte. 

In Table I are listed comprehensive citations of published methods for analyses of trace metals In body fluids and other clinical specimens by means of electrothermal atomic absorption spectrometry. Readers are cautioned that many of the early methods that are cited In Table I have become outmoded, owing to Improvements In Instrumentation for electrothermal atomic absorption spectrometry. All of the published methods need to be critically evaluated In the prospective analyst s laboratory before they can be confidently employed for diagnostic measurements of trace metals In body fluids. Despite these caveats, the author believes that Table I should be helpful as a guide to the growing literature on clinical and biological applications of electrothermal atomic absorption spectrometry. 

Inductively coupled plasma atomic emission spectrometry Electrothermal atomic absorption spectrometry High pressure liquid chromatography... 

P. Van Keerbergen, J. Smeyers-Verbeke and D.L. Massart, Decision support system for run suitability checking and explorative method validation in electrothermal atomic absorption spectrometry. J. Anal. Atomic Spectrom. inch Atomic Spectrom. Updates, 11 (2) (1996) 149-158. 

An AH, Smith BW, Winefordner JD (1989) Direct analysis of coal by electrothermal atomization atomic-absorption spectrometry. Talanta 36 893-896. 

Brown SS, Nomoto S, Stoeppler M, Sunderman FW Jr (1981) lUPAC reference method for analysis of nickel in serum and urine by electrothermal atomic absorption spectrometry. Clin Biochem 14 295-299. 

Acar 0, Kn ic Z, Turker AR (1999) Determination of bismuth, indium and lead in geological and sea-water samples by electrothermal atomic absorption spectrometry with nickel containing chemical modifiers. Anal Chim Acta 382 329-338. 

EDI-CI Electric discharge-induced chemical ionisation ETAAS, ET-AAS Electrothermal (atomisation) atomic absorption spectrometry... 

Aguilera de Benzo Z, Fraile R, Carrion N, et al. 1989. Determination of lead in whole blood by electrothermal atomization atomic absorption spectrometry using tube and platform atomizers and dilution with Triton X-100. Journal of Analytical and Atmospheric Spectrometry 4 397-400. 

Eaton AD, Clesceri LS, Greenberg AE. 1995c. Method 3113, Metals by Electrothermal Atomic Absorption Spectrometry, Standard Methods for the Examination of Water and Wastewater, American Public Health Association, Washington, DC. 

Xu Y, Liang Y. 1997. Combined nickel and phosphate modifier for lead determination in water by electrothermal atomic absorption spectrometry. Journal of Analytical Atomic Spectrometry 12(4) 471-474. 

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