Rapid residue analysis of four triazolopyrimidine herbicides in soil, water, and wheat by ultra-performance liquid chromatography coupled to tandem mass spectrometry

A sensitive and effective method for simultaneous determination of triazolopyrimidine sulfonamide herbicide residues in soil, water, and wheat was developed using ultra-performance liquid chromatography coupled with tandem mass spectrometry. The four herbicides (pyroxsulam, flumetsulam, metosulam, and diclosulam) were cleaned up with an off-line C18 SPE cartridge and detected by tandem mass spectrometry using an electrospray ionization source in positive mode (ESI+). The determination of the target compounds was achieved in < 2.0 min. The limits of detection were below 1 mu g kg(-1), while the limits of quantification did not exceed 3 mu g kg(-1) in different matrices. Quantitation was determined from calibration curves of standards containing 0.05-100 mu g L-1 with r (2) > 0.997. Recovery studies were conducted at three spiked levels (0.2, 1, and 5 mu g kg(-1) for water; 5, 10, and 100 mu g kg(-1) for soil and wheat). The overall average recoveries for this method in water, soil, wheat plants, and seeds at three levels ranged from 75.4% to 106.0%, with relative standard deviations in the range of 2.1-12.5% (n = 5) for all analytes.