DETERMINATION OF ARSENIC AND SELENIUM BY HYDRIDE GENERATION ATOMIC-ABSORPTION SPECTROMETRY USING A GAS-LIQUID SEPARATOR AND A DEHYDRATION TRAP

Hydride generated in a mixing coil was collected in a gas-liquid separ ator, dehydrated in a dehydration trap, and swept into an electrically heated furnace by manipulating electromagnetic relays and timers. Int erferences From transition metals were eliminated by the Chelex 100 se paration. Sharp peaks were recorded on a recorder. Detection limits (s ignal to noise ratio 3) of arsenic and selenium were 0.6 ng/ml and 1 n g/ml, respectively. Accuracies checked with biological standard refere nce materials obtained from the National Institute of Standards and Te chnology (NIST) of USA and the National Research Council (NRC) of Cana da were within the certified values except for those Of oyster tissue. (C) 1996 Academic Press, Inc.