[Determination of 67 pesticides in drinking water by solid phase extration disk extraction-gas chromatography-tandem mass spectrometry].

OBJECTIVE

To develop a method for the simultaneous determination of 67 pesticides in water by solid phase extration(SPE) disk extraction-gas chromatography-tandem mass spectrometry(GC-MS/MS).

METHODS

Pesticides in water were extracted and cleaned-up with SPE disk, then eluted with dichloromethane-n-ethyl acetate(7∶3, V/V). After the eluent being concentrated to 1 mL under nitrogen blow at 40 ℃, the supernatant was injected into GC-MS/MS for analysis. The GC separation was performed on a DB-5 MS capillary column(30 m×0. 25 mm×0. 25 μm). The pesticides were detected by MS/MS in multiple reaction monitoring(MRM) mode and quantified by working curve method.

RESULTS

The linear range of the method for most of the pesticides were in the range of 0. 05-5 μg/L with correlation coefficients of 0. 9924-0. 9999. The quantitative limits(S/N=10) of the method were in the range of 1. 0×10~(-5)-0. 059 μg/L. The recoveries for pesticides were 81. 0%-125. 0% with relative standard deviations of 1. 5%-21. 4%(n=6).

CONCLUSION

The method is sensitive, simple, environmentally friendly and suitable to the determination of pesticides in drinking water for rapid screening and quantitative analysis.