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Automated solid-phase extraction coupled to gas chromatography with electron-capture detection: a combination of extraction and clean-up of pyrethroids in the analysis of surface water.

G R van der Hoff·F Pelusio·U A Brinkman·R A Baumann·P van Zoonen
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Abstract

The combination of automated solid-phase extraction (SPE) and large-volume introduction gas chromatography electron-capture detection (GC-ECD) is used for the determination of synthetic pyrethroids in surface and drinking water. The selectivity that is needed for the use of GC-ECD of environmental samples is achieved by addition of a polarity modifier to the sample. In this study, sufficient methanol was added to 19 ml of sample to obtain a level of 30% of modifier prior to SPE. The cartridge is washed with one additional ml of 30% methanol in water. After drying, the cartridge is eluted with toluene. GC-ECD analysis is performed by on-column introduction of 100 microliters of the toluene extract. The whole procedure was automated by using an automated solid-phase extraction apparatus. Limits of detection (LODs) for the pyrethroids in surface water are in the range of 1 to 8 ng/1 (signal-to-noise ratio = 3); even lower limits of detection are possible for drinking water.

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AutoanalysisChromatography, GasInsecticidesPyrethrinsWaterWater PollutantsJournal ArticleResearch Support, Non-U.S. Gov't

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G R van der Hoff, F Pelusio, U A Brinkman, R A Baumann, P van Zoonen. 1996-01-05. Automated solid-phase extraction coupled to gas chromatography with electron-capture detection: a combination of extraction and clean-up of pyrethroids in the analysis of surface water.. https://doi.org/10.1016/0021-9673(95)00142-5

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