Vapor generation or electrothermal atomic absorption spectrometry? Both!

Whereas flame atomic absorption spectrometry (AAS) lacks sensitivity at analyte concentrations below 0.1 and 10 mu g g(-1) in analyses of liquid and solid samples, respectively, two modern AAS techniques with better detection power for quantitation at nanogram and picogram levels are employed: electrothermal AAS (ETAAS) and vapor generation AAS (VGAAS), viz. hydride generation AAS (HGAAS) or cold vapor technique for mercury (CVAAS). In this overview are discussed and illustrated the scope, merits, sample pretreatment requirements, methodological considerations and limitations of ETAAS, VGAAS and their recent hyphenations with each other (e.g. the VG-ETAAS coupling with in-atomizer trapping of hydrides and vapors) and with other separation/enrichment analytical techniques, aimed at solving important analytical problems of elemental trace analysis, microanalysis, speciation, etc. Optimum application fields are defined and examples from the author's recent research with biological and environmental matrices are given. (C) 2000 Elsevier Science B.V. All rights reserved.