EXPANDING THE WORKING CONCENTRATION RANGE IN GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY - EFFECT OF NONSTOP FLOW ON THE DETERMINATION OF TIN

Maintaining the carrier gas flow during the atomization step allows on e to expand the working linear range in metal determinations by graphi te furnace atomic absorption spectrometry (GFAAS). The effect of this operational mode on the precision of the analytical results for severa l atomic lines of tin is studied using atomization from the tube wall and from the platform. If atomization is carried out from the platform , maintaining the argon flow has no significant statistical effect on precision and allows the working range to be expanded to 8300 ng Sn vs . 1400 ng in the stop-flow mode with atomization from the tube wall. ( C) 1997 Elsevier Science B.V.