Abstract:
OBJECTIVE To establish a method for the simultaneous determination of 34 pesticide residues in Pseudostellariae Radix with combination of QuEChERS and gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS/MS).
METHODS Sample was extracted with acetonitrile, and the extract was further purified by dispersive solid-phase extraction. The prepared sample was analyzed by GC-MS/MS in multi-reaction monitoring mode and matrix-matched internal standard method was applied to quantify the pesticides. There were three supplemental levels for determing rates of recovery and RSD.
RESULTS All pesticides had good linearity with correlation coefficient higher than 0.997. The RSD of instruments precision were 0.3%-4.8%. The rates of recovery were 70.6%-106.9%, and the RSD of repeatability were 2.2%-7.4%. The limits of detection all<0.005 mg·kg
‒1.
CONCLUSION The method is simple, sensitive, accurate and reliable, and it can be used for the determination of 34 pesticide residues in Pseudostellariae Radix.