A new version of the pulsed discharge electron capture detector (PDECD
) has been developed and characterized. Changes to the old version inc
lude a slightly altered detector geometry, replacement of the polymer
insulation with sapphire and quartz, and the use of methane dopant gas
instead of nitrogen or hydrogen. Various operating parameters have be
en investigated and optimized, including discharge current, dopant gas
, bias voltage, and sample introduction position. The resulting detect
or is more inert and more sensitive (a limit of 36 fg for lindane) and
capable of operation at temperatures as high as 400 degrees C. By run
ning 23 halocarbon compounds on the improved PDECD and on a Ni-63-ECD
using the same GC system, we find that the PDECD is superior to Ni-63-
ECD in terms of sensitivity, linearity, and response time. We attribut
e the enhanced sensitivity to a lower positive ion concentration, whic
h its turn lowers the electron-positive ion rate of recombination. Pes
ticides (including some real-world samples) have also been analyzed on
the PDECD. The results demonstrate that the PDECD can replace the rad
ioactive ECD typically used in these analyses.