Atomic absorption spectrometry performance

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) ... 

Raw foods were freeze-dried and analyzed for carbon isotopes using mass spectrometry. Cooked foods were prepared following historic recipes, then were freeze-dried prior to analysis. For the trace element analysis, foods (both raw and cooked) were wet ashed using nitric acid in Teflon lined pressure vessels and digested in a CEM Microwave oven. Analysis of Sr, Zn, Fe, Ca and Mg was performed using Atomic Absorption Spectrometry in the Department of Geology, University of Calgary. 

In modern times, most analyses are performed on an analytical instrument for, e.g., gas chromatography (GC), high-performance liquid chromatography (HPLC), ultra-violet/visible (UV) or infrared (IR) spectrophotometry, atomic absorption spectrometry, inductively coupled plasma mass spectrometry (ICP-MS), mass spectrometry. Each of these instruments has a limitation on the amount of an analyte that they can detect. This limitation can be expressed as the IDL, which may be defined as the smallest amount of an analyte that can be reliably detected or differentiated from the background on an instrument. 

Hydride Generation Atomic Absorption Spectrometry High Performance Liquid Chromatography High Performance Thin-Layer Chromatography High Resolution... 

Adsorptive cathodic stripping voltammetry has an advantage over graphite furnace atomic absorption spectrometry in that the metal preconcentration is performed in situ, hence reducing analysis time and risk of contamination. Additional advantages are low cost of instrumentation and maintenance, and the possibility to use adapted instrumentation for online and shipboard monitoring. 

A typical measurement was performed as follows. The feeder was lowered into the crucible and the sample solution (seawater) was allowed to flow under an inert atmosphere with the suction on. A constant current was applied for a predetermined time. When the pre-electrolysis was over, the flow was changed from the sample to the ammonium acetate washing solution, while the deposited metals were maintained under cathodic protection. Ammonium acetate was selected for its low decomposition temperature, and a 0.2 ml 1 1 concentration was used to ensure sufficient conductivity. At this point the feeder tip was raised to the highest position and the usual steps for an electrothermal atomic absorption spectrometry measurement were followed drying for 30 s at 900 C, ashing for 30 s at 700 °C, and atomization for 8 s at 1700 °C, with measurement at 283.3 nm. The baseline increases smoothly with time as a consequence of an upward lift of the crucible caused by thermal expansion of the material. 

Monien and Stangel [598] studied the performance of a number of alternative chelating agents for vanadium, and their effect on vanadium analysis, by atomic absorption spectrometry with volatilisation in a graphite furnace. Two promising compounds were evaluated in detail, namely 4-(2-pyridylazo) resorcinol in conjunction with tetraphenylarsonium chloride and tetramethylenedithiocar-bamate. These substances, dissolved in chloroform, were used for extraction... 

Analytical model, assumptions and practical implications, 52-57 Analytical performance, correlation chromatography, 108 Analytical process, steps of, 7 Aroclors, isomer-specific analysis of, application of SIMCA, 195-232 Atomic absorption spectrometry, determination of iron in water, 116... 

Five liquid membrane electrodes (Table 13.3) are now commercially available and have found wide application in the testing of electrolytes in biological and technological systems. All five electrodes perform well in the concentration range over which the Nernstian slope is maintained, i.e., from 10 -10 moldm . These electrodes to a certain extent have replaced in both chemical and clinical laboratories the more traditional instrumental methods of analysis, such as flame photometry and atomic absorption spectrometry. There are, of course, many more liquid membrane electrodes, but the availability of satisfactory solid electrodes has greatly restricted their development and practical application. 

An analyte transport efficiency of nearly 100% has been obtained with an interface for flame atomic absorption spectrometry (FAAS) [3]. It has been used for the determination of lead in blood [5] and for coupHng with a high-performance Hquid chromatograph (HPLC) [6]. 

The following blank-corrected readings were obtained for the determination of nickel in steel, using nickel standards dissolved in iron solution (10 g k ). The determination was performed by atomic absorption spectrometry using an air-acetylene flame and the 232 nm nickel line. 

The contribution of flow analysis to improving the performance of atomic spectrometry is especially interesting in the field of standardisation. FIA can provide a faster and reliable method to relate the absorbance, emission or counts (at a specific mass number) to the concentration of the elements to be determined. In fact, flow analysis presents specific advantages to solving problems related to the sometimes short dynamic concentration ranges in atomic absorption spectrometry, by means of on-line dilution. The coupling of FI techniques to atomic spectrometric detectors also offers tremendous possibilities to carry out standard additions or internal standardisation. 

M. Grotti, P. Rivaro and R. Frache, Determination of butyltin compounds by high-performance liquid chromatography-hydride generation-electrothermal atomisation atomic absorption spectrometry, J. Anal. At. Spectrom., 16(3), 2001, 270-274. 

C. Schickling and J. A. C. Broekaert, Determination of mercury species in gas condensates by online coupled high-performance liquid chromatography and cold-vapor atomic absorption spectrometry, Appl. Organo-met. Chem., 9(1), 1995, 29-36. 

Carbon Monoxide. Methods for determining carbon monoxide include detection by conversion to mercury vapor, gas filter correlation spectrometry, TDLAS, and grab sampling followed by gas chromatograph (GC) analysis. The quantitative liberation of mercury vapor from mercury oxide by CO has been used to measure CO (73). The mercury vapor concentration is then measured by flameless atomic absorption spectrometry. A detection limit of 0.1 ppbv was reported for a 30-s response time. Accuracy was reported to be 3% at tropospheric mixing ratios. A commercial instrument providing similar performance is available. 

In an interlab oratory study involving 160 accredited hazardous materials laboratories reported by Kimbrough and Wakakuwa [28], each laboratory performed a mineral acid digestion on five soils spiked with arsenic, cadmium, molybdenum, selenium and thallium. Analysis of extracts was carried out by atomic emission spectrometry, inductively-coupled plasma mass spectrometry, flame atomic absorption spectrometry and hydride generation atomic absorption spectrometry. 

Experiments were performed in Teflon-lined titanium autoclaves, submerged in a thermostated oil bath. The supernatant liquors were analyzed using atomic absorption spectrometry. Solid residues were washed with water, dried and examined by the following surface analytical methods ... 

AMS = accelerated mass spectroscopy EDTA = ethylene diamine tetra acetic acid GFAAS = graphite furnace atomic absorption spectrometry ICP-AES = inductively coupled plasma - atomic emission spectroscopy NAA = neutron activation analysis ETAAS = electrothermal atomic absorption spectrometry SEC/ICP-MS = size-exclusion chromatography/ICP-AES/mass spectrometry HLPC/ICP-AES = high-performance liquid chromatography/ICP-AES LAMMA = laser ablation microprobe mass analysis NA = not applicable ppq = parts per quadrillion... 

Wrobel K, Gonzalez EB, Wrobel K, et al. 1995. Aluminum and silicon speciation in human serum by ion-exchange high-performance liquid chromatography-electrothermal atomic absorption spectrometry and gel electrophoresis. Analyst 120 809-815. 

Diemer, J. and Heumann, K.G. (1997) Bromide/bromate speciation by NTI-IDMS and ICP-MS coupled with ion exchange chromatography. Fresenius J. Anal. Chem., 357,74-79. Duan, YX., Wu, M., Jin, Q.H. and Hieftje, G.M. (1995) Vapour generation of nonmetals coupled to microwave plasma-torch mass-spectrometry. Spectrochim. Acta B, 50,355-368. Ebdon, L., Hill, S. and Jones, R (1987) Interface system for directly coupled high performance liquid chromatography-flame atomic absorption spectrometry for trace metal determination./. Anal. At. Spectrom., 2, 205-210. 

Hansen, S.H., Larsen, E.H., Pritzi, G. and Cornett, C. (1992) Separation of seven arsenic compounds by high performance liquid chromatography with on-line detection by hydrogen-argon flame atomic absorption spectrometry and inductively coupled plasma mass spectrometry./. Anal. At. Spectrom., 1, 629-634. 

Basic techniques for speciation analysis are typically composed of a succession of analytical steps, e.g. extraction either with organic solvents (e.g. toluene, dichloromethane) or different acids (e.g. acetic or hydrochloric acid), derivatisa-tion procedures (e.g. hydride generation, Grignard reactions), separation (gas chromatography (GC) or high-performance liquid chromatography (HPLC)), and detection by a wide variety of methods, e.g. atomic absorption spectrometry (AAS), mass spectrometry (MS), flame photometric detection (FPD), electron capture detection (ECD), etc. Each of these steps includes specific sources of error which have to be evaluated. 

Figure 6.1 Bar-graph of MeHg in CRM 580. The results correspond to six replicate determinations as performed by different laboratories using various methods. MEANS indicates the mean of laboratory means with 95% confidence interval. Abbreviations-. CVAAS, cold vapour atomic absorption spectrometry CVAFS, cold vapour atomic fluorescence spectrometry ECD, electron capture detection GC, gas chromatography HPLC, high-performance liquid chromatography ICPMS, inductively coupled plasma mass spectrometry MIP, microwave induced plasma atomic emission spectrometry QFAAS, quartz furnace atomic absorption spectrometry SFE, supercritical fluid extraction.

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