The combination of flow injection techniques with vapor generation ato
mic absorption spectrometry (VGAAS) was shown to significantly improve
the overall performance of the latter. Recently, new developments in
this field have made possible further enhancements in sensitivity and
selectivity, including: (1) selectivity enhancement by optimization of
kinetic conditions (2) selectivity enhancement by on-line separation
of interferents (3) selectivity enhancement by on-line sample matrix m
odification (4) FI-HGAAS with sensitivity enhancement by reagent addit
ion (5) sensitivity enhancements by on-line coprecipitation preconcent
ration (6) sensitivity enhancements by in situ preconcentration of hyd
rides in a graphite furnace. These are illustrated by applications in
the trace or ultratrace determination of germanium, selenium, arsenic,
antimony, bismuth, tin, and lead in environmental samples and Chinese
herbal medicine. (C) 1996 Academic Press, Inc.