Atomic absorption spectrometry with liquid chromatography

Investigations of lead speciation in various environmental samples have relied upon gas and liquid chromatographic separations coupled to mass spectrometric and atomic absorption spectrometric detectors. The combination of atomic absorption spectrometry with gas chromatography (GC-AAS) has proved to be the most widely applied technique. Sample types have included air, surface water, air particulates, sediments, grass, and clinical materials such as blood. A review of speciation analyses of organolead compounds by GC-AAS, with emphasis on environmental materials, was published (Lobinski et al., 1994). 

Techniques for analysis of different mercury species in biological samples and abiotic materials include atomic absorption, cold vapor atomic fluorescence spectrometry, gas-liquid chromatography with electron capture detection, and inductively coupled plasma mass spectrometry (Lansens etal. 1991 Schintu etal. 1992 Porcella etal. 1995). Methylmercury concentrations in marine biological tissues are detected at concentrations as low as 10 pg Hg/kg tissue using graphite furnace sample preparation techniques and atomic absorption spectrometry (Schintu et al. 1992). 

M. A. Lopez, M. M. Gomez, C. Camara, Determination of six arsenic species by high-performance liquid chromatography - hydride generation - atomic absorption spectrometry with on-line thermo-oxidation, Fresenius J. Anal. Chem, 346 (1993), 643-647. 

Atomic absorption spectrometry with flame (AA-F) or electrothermal atomization furnace (AA-ETA), inductively coupled plasma-emission spectroscopy (ICP-ES), inductively coupled plasma-mass spectrometry (ICP-MS), and high-performance liquid chromatography-mass spectrometry (LC-MS) are state-of-the-art analytical techniques used to measure metals in biological fluids. They are specific and sensitive and provide the cfinical laboratory with the capability to measure a broad array of metals at clinically significant concentrations. For example, ICP-MS is used to measure several metals simultaneously. Photometric assays are also available but require large volumes of sample and have limited analytical performance. Spot tests are also... 

Falter R and Scholer HE (1994) Interfacing high-performance liquid chromatography and cold vapour atomic absorption spectrometry with on-line UV... 

Zhang X, Cornelis R, De Kimpe J, and Mees L (1996) Arsenic speciation in serum of uraemic patients based on liquid chromatography with hydride generation atomic absorption spectrometry and on-line UV photo-oxidation digestion. Anal Chim Acta 319 177-185. 

Principles and Characteristics Plasma source techniques are more widely used in connection with liquid chromatography than atomic absorption spectrometry (see Section 7.3.3). ICP is a natural complement to liquid chromatography, and HPLC-ICP procedures... 

Measurement techniques that can be employed for the determination of trace metals include atomic absorption spectrometry, anodic stripping voltammetry, differential pulse cathodic stripping voltammetry, inductively coupled plasma atomic emission spectrometry, liquid chromatography of the metal chelates with ultraviolet-visible absorption and, more recently, inductively coupled plasma mass spectrometry. 

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.

High, K.A., Azani, R., Fazekas, A.F., Chee, Z.A. and Blais, J.-S. (1992) Thermospray-microatomizer interface for the determination of trace cadmium and cadmium-metallothioneins in biological samples with flow injection- and high-performance liquid chromatography-atomic absorption spectrometry. Anal. Chem., 64, 3197-3201. 

High performance liquid chromatography coupled with hydride generation-atomic absorption spectrometry has been used for the determination of arsenic species in non saline water samples [265],... 

G. Alsing Pedersen, E. H. Larsen, Speciation of four selenium compounds using high performance liquid chromatography with on-line detection by inductively coupled plasma mass spectrometry or flame atomic absorption spectrometry, Fresenius J. Anal. Chem., 358 (1997), 591-598. 

Sarica, D.Y., Turker, A.R., and Erol, E. Onhne speciation and determination of Cr(III) and CrfVt) in drinking and waste water samples by reversed-phase high performance liquid chromatography coupled with atomic absorption spectrometry. J. Sep. Sci. 2006, 29,1600-1606. 

Ko, F.H., Chen, S.L., and Yang, M.H. Evaluation of the gas-liquid separation efficiency of a tubular membrane and determination of arsenic species in groundwater by liquid chromatography coupled with hydride generation atomic absorption spectrometry. J. Anal. Atom. Spectrom. 1997, 12, 589-595. 

A second extended function of the liquid column chromatography is to preseparate trace amounts of several substances for subsequent quantitative analysis by a selective determination method such as atomic absorption spectrometry (Table 2.3). Here often only a particular degree of separation is achieved. Non separated elements are to be determined with high-selective methods. In most cases an enrichment is combined with these chromatographic methods (Chap. 4). 

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