Method for detecting residual quantity of methylthiophosphorus by LC-MS/MS (liquid chromatography-mass spectrometry/mass spectrometry) and application of method

The invention discloses a method for detecting residual quantity of methylthiophosphorus by LC-MS/MS. The method comprises the following steps: sample extraction, sample purification, sample determination and result analysis. By adopting a specific polystyrene filler solid-phase extraction column, the purification effect on an analyte is improved, the interference of other components on methylthiophosphorus is reduced, and the detection accuracy is improved. And the detection accuracy is improved. In addition, a heptamethyltrisiloxane-terminated octadecyl silica gel column is adopted as a liquid chromatographic column, so that the combination stability of an analysis sample and a stationary phase is improved, and the reproducibility and precision of experimental data are improved. Meanwhile, by setting the high and low mass resolution of a quadrupole in the LC-MS/MS, the linear distribution of linear measurement of analytes is improved, the interference of false positive signals is reduced, and the detection