Hydride trapping in quartz atomizers. A radiotracer study

Complete text of publication follows. A trap-and-atomizer device based on multiatomizer has been described recently. This compact and universal device enables to preconcentrate As, Sb, Bi and Se hydrides on-line prior their AAS detection. In this work, 125Sb and 205,206Bi radioactive indicators were used to (1) quantify the efficiency of the individual steps of preconcentration procedure and (2) to investigate the spatial distribution of the analytes in a quartz trap. Trapping efficiency of Sb was better than 92% (RSD6%) between 200 and 900 deg C. Trapping efficiency of Bi was above 96%(RSD5%) between 100 and 800 deg C whereas it has fallen to 83% at 900 deg C. Autoradiography showed that the area of the trapping spot increased with increasing trapping temperature. The trap is capable to trap up to 400 ng of Bi and 2ng of Sb, respectively. Typically, 1-10 ng of analyte is preconcentrated in ultratrace analysis. Also the volatilization step was proved to be efficient - only (1.81.6)% and (2.90.9)% of original Bi and Sb activity, respectively, was found in the traps after the volatilization. Results from our recent radiotracer study will be compared to those obtained previously with AAS detection. Potential of hydride trapping in quartz atomizers will be discussed. Financial supports from the Grant Agency of the ASCR (Project No. A400310507), Institute of Analytical Chemistry AS CR (Project No. AV0Z40310501) and the Grant Agency of Charles University (Project No. GAUK 306/2006/B-CH/PrF) are highly acknowledged.