Sensitive and simultaneous determination of nine anticoagulant rodenticides in human blood by UPLC-MS-MS with phospholipid removal pretreatment.

A sensitive and rapid method for the simultaneous determination of nine anticoagulant rodenticides (ARs) in human blood is reported herein. The method involves phospholipid removal pretreatment for reduced matrix effect (ME) and detection with ultra-performance liquid chromatography coupled with tandem mass spectrometry. Satisfactory recoveries were achieved ranging from 80.6% to 113.1% for the nine analytes, with the intra-day relative standard deviations (RSDs) in the range of 3.4-7.9% and inter-day RSDs in the range of 4.1-8.3%, indicating good precision. Linear relationships with correlation coefficients above 0.998 (n = 6) were found in the range of 1-2,000 ng/mL. High sensitivity was achieved with limits of detection ranging from 0.02 to 0.3. The application of phospholipid removal step significantly optimized the ME, and the reduction of ME ranged from 6.1% to 15.5%. This method was successfully applied to the determination of ARs for blood samples from real forensic cases. These results prove that this method is reliable for rapid forensic and clinical diagnosis. The removal capabilities for five representative phospholipids that are abundant in blood were evaluated individually with Phree™ phospholipid removal plates. While significant capabilities for phospholipid removal were confirmed, the results showed that the removal capability for certain phospholipid could be improved.