Stibine preconcentration in a quartz trap with subsequent atomization in the quartz multiatomizer for atomic absorption spectrometry

A preliminary evaluation of a simple (bare) quartz tube trap for collection of SbH3 and for volatilization of trapped analyte with subsequent atomization in a multiple microflame quartz tube atomizer (multiatomizer) for atomic absorption spectrometry is presented. The influence of relevant experimental parameters on the collection/volatilization efficiency was investigated. The parameters studied Were: collection temperature and time, volatilization temperature and flow rates of air and hydrogen for the volatilization. Under optimized conditions, the collection/volatilization efficiency was 65%. For the collection time of 120 s (sample volume of 8 ml), the detection limit was 3.9 pg ml(-1), and the analytical plot was linear up to 1.25 ng ml(-1). Possible ways of improving the performance of the set-up as well as the collection/volatilization efficiency are suggested

Metal furnace heated by flame as a hydride atomizer for atomic absorption spectrometry: Sb determination in environmental and pharmaceutical samples

The present work describes a metallic hydride atomizer for atomic absorption spectrometry, by evaluating the performance of the Inconel 600 (R) tube. For this purpose, stibine was used as the model volatile compound and antimony determination in river and lake sediments and in pharmaceutical samples was carried out to assess the metal furnace performance. Some parameters are evaluated such as those referring to the generation and transport of the hydride (such as KBH4 and acid concentrations, carrier gas flow rate, injected volume, etc.), as well as those referring to the metal furnace (such as tube hole area, flame composition, long-term stability, etc.). The method presents linear Sb concentration from 2 to 80 fig L-1 range (r > 0.998; n = 3) and the analytical frequency of ca. 140 h(-1). The limit of detection (LOD) is 0.23 mu g L-1 and the precision, expressed as R.S.D., is less than 5% (40 mu g L-1; n = 10). The accuracy is evaluated through the reference materials, and the results are similar at 95% confidence level according to the t-test. (c) 2007 Elsevier B. B.V. All rights reserved.73462162

Gold volatile compound generation: optimization, efficiency and characterization of the generated form

The generation of an analytically useful volatile form of Au has been studied. The flow injection generation was performed in a dedicated generator consisting of a special mixing apparatus and gas-liquid separator design in the presence of surfactants (Triton X-100, Antifoam B) and diethyldithiocarbamate. The on-line atomization in the quartz tube multiatomizer for atomic absorption (AAS) detection has been employed as the convenient atomization/detection means. The optimization of generation and atomization conditions resulted in an analytical procedure yielding the detection limit of 17 ng ml(-1) and a very good long range reproducibility of the analytical signal. A 198,199 Au radioactive indicator of high specific activity together with AAS measurements was used to track quantitatively the transfer of analyte in the course of generation and transport to the atomizer and to determine the generation efficiency of 11.9 +/- 0.1% at the Ar carrier flow rate optimized for the multiatomizer of 240 ml min(-1). The efficiency was twice as high at the Ar carrier flow rate of 600 ml min(-1). In situ trapping in GF for AAS was explored as an alternative to the on-line atomization. The detection limit of 3.0 ng ml(-1) was achieved even though the Ar flow rate optimum for trapping (115 ml min(-1)) was too low for efficient generation: the overall efficiency of generation and trapping was 1.11 perpendicular to 0.03%. Transmission electron microscopy measurements proved the presence of Au nanoparticles of diameter of approximately 10 nm and smaller transported from the generator by the flow of carrier Ar