METHODS FOR THE ANALYSIS OF SORBENT CONCENTRATE IN GRAPHITE-FURNACE AAS

Two methods are described for the GFAAS analysis of a sorbent concentr ate used in the determination of Cd, Co, Cu, Ni, and Pb in high-minera lized waters and of Se in biological samples. The sorbent concentrate was introduced into the graphite furnace in the form of a powder as we ll as in suspension. Ultrasonic mixing and introduction of the suspens ion by autosampler reduces the RSD to 0.02-0.03% and enables the deter mination of elements at lower determination limits: Cd = 0.01 mu g/L, Co = 0.05 mu g/L, Cu and Ni = 0.4 mu g/L, Pb = 0.2 mu g/L, and Se = 0. 05 mu g/L.