Rapid target analysis for pesticides in water by online coated capillary microextraction combined with liquid chromatography and tandem mass spectrometry

Abstract

The applicability of online trace enrichment with custom-made coated capillaries combined with tandem mass spectrometry was demonstrated for the target analysis of selected pesticides (mainly herbicides, e.g., triazines, phenylureas, and acetanilides) in water. The developed method allows rapid determination of several widely used plant protectants within a total analysis time of 11 min. Good linearity (r ≥ 0.995) was obtained for the selected pesticides in the range of 0.050-50 μg/L. The relative standard deviations (RSDs) of the peak areas were ≤3.8% for spiked Milli-Q water (5 μg/L). The RSDs obtained in analyses of spiked (1 μg/L) water samples (brook water, river water, sewage plant effluent) ranged from 2.9 to 6.8%, indicating low influence of the matrix on enrichment and detection. The detection limits, which ranged from 10 to 90 ng/L, fulfilled the requirements of the European regulations for drinking water. The polyacrylate coating of the extraction capillary showed good stability in the presence of water and acetonitrile and allowed ≥100 extractions with 1 capillary.