Solid phase microextraction arrow-ion mobility spectrometry for determination of selected pesticides in water

Abstract

Ion mobility spectrometry with corona discharge ion source was used for the measurements of selected pesticides cybutryne, terbutryn, dichlorvos, and quinoxyfen in water. The analyses were carried out by (i) direct injection of the aqueous solution of the pesticides and (ii) extraction using solid phase microextraction by commercial SPME arrows. The instrumental and the experimental extraction parameters including the drift tube temperature, injection port temperature, and the SPME fiber type were studied and optimized to achieve the maximum signal intensity. The limit of detections obtained by the direct injection were about 0.1–1.0 mg L−1. Using the SPME arrow-ion mobility spectrometry method, the detection limits were improved 7–50 times and obtained as 0.01, 0.015, 0.05, and 0.1 mg L−1 for terbutryn, dichlorvos, cybutryne, and quinoxyfen, respectively. The recovery rate for analysis in surface water (real samples) was approximately 90–110% for both the direct injection and solid phase microextraction method. The capability of ion mobility spectrometry for the simultaneous detection of a mixture of the studied pesticides was assessed, and it was found that terbutryn, dichlorvos, and quinoxyfen can be detected simultaneously without peak overlapping.