Determination of halosulfuron-methyl herbicide in sugarcane juice and tomato by capillary electrophoresis–tandem mass spectrometry

A capillary electrophoresis–tandem mass spectrometry (CE–MS/MS) method for the determination of halosulfuron-methyl (HSU) residue in samples of sugarcane juice and tomato is introduced and validated. The samples were submitted to a QuEChERS extraction procedure followed by electrophoretic separation in NH4HCO3 electrolyte (adjusted to pH 8.5) and detection by electrospray-tandem mass spectrometry. The total HSU migration took place in less than 3.5 min, and the detection was accomplished by monitoring three fragmentation processes of this anion: m/z 435–182, 139, and 83. The R2 values for concentrations up to 100 ppb (μg kg−1) were, respectively, 0.992, 0.992, and 0.978. Recovery values for samples spiked at three concentration levels (10, 20 and 50 ppb) were in the range of 96–104% with standard deviation not greater than 5.0%. The limit of detection for HSU in sugarcane juice and tomato was 2 ppb for both samples.