Various ELCADlike
discharge arrangements have been investigated in different
laboratories, mostly for achieving miniaturized and/or simplified
analytical methods.20-27 One particularly simple design, referred
to as a solution-cathode glow discharge (SCGD),28-30 has recently
been developed by the Hieftje group. This new version offers
greatly reduced size and improved emission sensitivity. It exhibits
detection limits and precision levels approaching or even better
than those obtainable by inductively coupled plasma atomic
emission spectrometry (ICP-AES) for a range of elements.
However, its detection limits for Hg30 are still in the range of tens
of micrograms per liter, which is still not adequate for direct Hg
determination in many environmental or food samples.