Gas Chromatography Detectors - Ionization Detectors > The Pulsed Discharge Electron Capture Detector > Page 79


Column DB–6, 30m x 0.25 mm; df 0.25 mm


1 Lindane 81 pg 2 Heptachlor 162 pg
3 Aldrin 162 pg 4 p,p'–DDE 162 pg
5 Dieldrin 162 pg 6 Endrin 324 pg
7 o,p'–DDT 324 pg 8 Mirex 486 pg


Courtesy of Valco Instruments Company Inc.


Figure 45 The Separation of Some Pesticides Monitored by the Valco Pulsed Discharge Electron Capture Detector


The linear dynamic range is also not precisely clear from the original publication but appears to be at least three orders of magnitude for a response index of (r) where 0.97 < r < 1.03, but this is an estimate from the data published. The modified form of the electron capture detector,devoid ofaradioactivesource,is obviously an attractive alternative to the conventional device and appears to have similar, if not better, performance characteristics. An example of the use of the pulsed discharge electron capture detector to monitor the separation of a mixture of pesticides is shown in figure 45.


In general, the electron capture detector is used extensively in forensic analyses and in environmental chemistry. It is very simple to use and is one of the least expensive, high sensitivity selective detectors available.