Vapor generation and atom traps: Atomic absorption spectrometry at the ng/L level


Ataman O. Y.

SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY, cilt.63, sa.8, ss.825-834, 2008 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 63 Sayı: 8
  • Basım Tarihi: 2008
  • Doi Numarası: 10.1016/j.sab.2008.03.013
  • Dergi Adı: SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.825-834
  • Anahtar Kelimeler: atom trapping, quartz trap, W-coil trap, atomic absorption spectrometry, hydride generation, enhancement factor, MINIATURE ELECTROTHERMAL DEVICES, TUNGSTEN FILAMENT ATOMIZER, HYDRIDE FORMING ELEMENTS, MOLYBDENUM FOIL STRIP, QUARTZ TUBE ATOMIZERS, HEATED W-COIL, FLAME AAS, ONLINE PRECONCENTRATION, MULTIPLE MICROFLAME, SELENIUM HYDRIDE
  • Orta Doğu Teknik Üniversitesi Adresli: Hayır

Özet

Atom-trapping atomic absorption spectrometry is a technique that allows detection at the ng/L level for several analytes such as As, Se, Sb, Pb, Bi. Cd, In, TI, Te, Sn and Hg. The principle involves generation of volatile species, usually hydrides, trapping these species on the surface of an atom trap held at an optimized temperature and, finally, revolatilizing the analyte species by rapid heating of the trap and transporting them in a carrier gas to a heated quartz tube, as commonly used with hydride generation AAS systems. A transient signal having, in most cases, a full width at half maximum of less than 1 s is obtained. The atom trap may be a quartz surface or a W-coil; the former is heated externally and the latter is heated resistively. Both collection and revolatilization temperatures are optimized. In some cases, the W-coil itself is used as an electrothermal atomizer and a heated quartz tube is then not needed. The evolution of these traps starts with the wellknown Watling's slotted quartz tube (SQT), continues with atom trapping SQT and finally reaches the present traps mentioned above. The analytical figures of merit for these traps need to be standardized. Naturally, enhancement is on characteristic concentration, Co, where the change in characteristic mass. mo. can be related to trapping efficiency. Novel terms are suggested for E, enhancement factor; such as E..., maximum enhancement factor; E, enhancement for 1.0 minute sampling and E, enhancement for 1.0 ml. of sample. These figures will allow easy comparison of results from different laboratories as well as different analytes and/or traps. (c) 2008 Elsevier B.V. All rights reserved.