electron capture detector (ECD)

A device that responds to decreases in an electrical current as the analyte passes through a plasma.
In ECD, a detector ionizes solutes by collision with metastable carrier-gas molecules produced by ß-emission from a radioactive source such as 63Ni. The electron-capture detector is one of the most sensitive detectors, and it responds strongly to halogenated solutes and others with high electroncapture cross-sections.