Gas chromatographic properties of the M series of universal retention index standards and their application to pesticide analysis.

The suitability of alkylbis(trifluoromethyl)phosphine sulphides for use as universal retention-index standards has been confirmed. In routine work, the M series were detected at the level of 0.4-0.6 pmol with flame ionization detection (FID), 2-7 fmol with alkaline thermionization detection (ATD) and 3-5 fmol with electron-capture detection (ECD). The sensitivities of ATD and ECD are so much greater than that of FID that their simultaneous use with FID is not possible. The sensitivities of ECD and ATD are similar enough that parallel use is possible. Examples of two-channel retention-index monitoring of pesticides from real samples are given.