Rapid Simultaneous Screening and Detection of 12 Anticoagulant Rodenticides in Food by Ultra-performance Liquid Chromatography-Triple Quadrupole/Linear Ion Trap Tandem Mass Spectrometry

A rapid analytical method for the simultaneous screening and detection of 12 anticoagulant rodenticides in food samples was established based on modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) sample preparation method using an ultra-performance liquid chromatography-triple quadrupole/linear ion trap tandem mass spectrometry (UPLC-QTrap-MS/MS). Food samples were extracted and purified with modified QuEChERS method. The 12 anticoagulant rodenticides (warfarin, brodifacoum, difethialone, coumachlor, coumatetralyl, bromadiolone, chlorophacinone, difenacoum, diphacinone, pindone, valone, and flocoumafen) and the internal standard (warfarin-D-5) were separated within 6 min using an ACQUITY UPLC BEH-C18 column (1.7 mu m, 2.1 mm x 50 mm) and gradient elution with the mobile phase consisting of 5 mM ammonium acetate formate buffer and acetonitrile. The multiple reaction monitoring-information dependent acquisition-enhanced product ion (MRM-IDA-EPI) scanning was employed for detection. The calibration curves were linear (R (2) > 0.99) for all the compounds. The mean recoveries for the 12 analytes at three spiked levels (1x LOQ, 5x LOQ, and 10x LOQ) were in the range of 79.5-113.2% with RSDs of 1.8-13.2%.The limits of detection (LOD) for the 12 rodenticides ranged from 0.01 (warfarin) to 0.05 mu g/kg (diphacinone). The limit of quantification (LOQ) for the 12 rodenticides was between 0.02 (warfarin) and 0.10 mu g/kg (diphacinone). The developed method was more straightforward, less time and labor intensive, and more sensitive, selective, and accurate for screening multiple anticoagulant rodenticides, and it was successfully used in several poisoning cases.