Abstract
One of the advantages of the flow injection (FI) concept is that
it is compatible with virtually all detection techniques. Being a
versatile vehicle for enhancing the performance of the individual
detection devices, the most spectacular results have possibly been
obtained in conjunction with atomic absorption spectrometry (AAS).
Initially with flame-AAS (fAAS) procedures, later for hydride
generation (HG) techniques, and most recently in combination with
electrothermal AAS (ETAAS). The common denominator for all these
procedures is the inherently precise and strictly reproducible
timing in FI from the point of sample injection/introduction to
the point of detection. Hence, in FI-fAAS this feature allows not
only to obtain improved repeatability but also improved accuracy,
and because the wash to sample ratio is high it permits the
handling of samples with elevated salt contents - which in
conventional operation readily might lead to clugging of the
burner. In FI-HG procedures it entails several advantages: Thus,
via the generation of the gaseous hydride the analyte is
effectively separated from the constituents of the matrix
material. Furthermore, the rigorous and exact timing of FI in many
instances makes it possible to exploit kinetic discrimination
towards species which by their presence potentially might
interfere in the hydride generation process or act as mediators
for the degradation of the hydrides formed. And not the least, the
FI-HG approach opens entirely new avenues for performing suitable
on-line sample pretreatment and preconcentration procedures prior
to the hydride generation process itself. In FI-ETAAS - which only
recently has been explored at any appreciable extent - it promises
to yield new and exciting possibilities for determining ultra-low
concentrations of a number of (especially HG- forming) elements.
In the words of the one of the authorities of AAS and foremost
pioneers of FI-AAS - Professor Z. L. Fang, who is the author on
two recently published monographs on this hyphenated technique -
the impact of FI on AAS is "so dramatic" that it has brought "new
vitality to a technique [AAS] which otherwise seemed to be
confronted by a period of stagnancy". The communication
demonstrates, by several practical examples, especially selected
from works conducted in the author's own group, this new vitality.
Original language | Danish |
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Journal | dansk kemi |
Volume | 77 |
Issue number | 9 |
Pages (from-to) | 18-23 |
Publication status | Published - 1996 |
Event | The 15th Nordic Atomic Spectroscopy and Trace Element Conference - Ebeltoft, Denmark Duration: 2 Jun 1996 → 6 Jun 1996 |
Conference
Conference | The 15th Nordic Atomic Spectroscopy and Trace Element Conference |
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Country/Territory | Denmark |
City | Ebeltoft |
Period | 02/06/1996 → 06/06/1996 |