Thermospray flame furnace atomic absorption spectrometry (TS-FF-AAS) -: a simple method for trace element determination with microsamples in the μg/1 concentration range

A new flame method of atomic absorption spectrometry has been developed. The liquid sample to be analyzed is transported through a very hot, simple metal capillary tip acting as a flame-heated thermospray into a glowing atomization tube (flame furnace) which is positioned into the air/acetylene flame of a standard flame-AAS burner head. Both the complete introduction of the whole sample and the ex-tended residence time inside the absorption volume result in an improvement of detection Limits from 14 to 67 for five investigated elements. The detection limits determined using 10-mu 1 samples amount to 0.19 ng/ml (Cd), 1.3 ng/ml (Cu), 5.2 ng/ml (T1), 13 ng/ml (Pb) and 21 ng/ml(Hg). A relative standard deviation of 1.4-3.4% (N = 12, 10 mu 1) was achieved. Sample volumes between 2.5 mu 1 and 200 mu 1 have been investigated. In the case of 10 mu 1 the sampling frequency was three per minute. The method can also be considered as a simple, effective interface between HPLC or FIA techniques and flame AAS. The determinations can be easily automated. (C) 2000 Elsevier Science B.V. All rights reserved.