Volume 46, Number 1 (January - February 2001)

Key words:  antimony, hydride generation, atomic absorption spectrometry, flow-injection analysis

The paper presents a design and construction of a simple set for determination of antimony and other hydride forming elements working on the basis of the method of injection-flow analysis with hydrides generation. The construction of the set is based on a commercially available flow system and bistable injection vavle. The effect of position of the injection vavle with respect to the peristaltic pump and the kind of measurements (the peak aera or the peak height), was analysed. The limits of determination were established as 2.1-0.06 ng ml^-1 for different volumes of the injection loops, 50-850 ml, and the precsion was 10.0-0.8 % respectively. The lowest limits of determination were obtained for the valve mounted behind the peristaltic pump (at the pumping side of the pump) and for measurements of the peak height. When the valve was mounted in front of the perisataltic pump, the lowest limit of determination was obtained for measurements of the aera under the peak. Preliminary results illustrating the performance of the set were obtained, determining the level of antymony in samples of natural waters (river, lake and underground waters) in the range from 0.20 ng ml^-1 to 0.7 ng ml^-1.