Simultaneous Determination of Amitraz and its Metabolites in Blood by Support Liquid Extraction Using UPHLC-QTOF

Abstract

This paper describes the use of UPHLC-QTOF for the analysis of pesticide amitraz and its metabolites in human blood. UPHLC-QTOF working in full scan mode simultaneously with a single MS/MS scan at 10 eV was employed to analyze in solid-support liquid-liquid extracts (SLE) of the human blood. Detection and quantification were carried out using full scan data (protonated molecules [M+H]+) while MS/MS data were used for fragment identification only. MS/MS scans were not found to have any negative influence on quantitation under the applied conditions. Verification studies were accomplished at low concentrations (1 ng/mL), and accuracy errors lower than 5 ppm were achieved. The human blood extracts spiked at LOQ and three QC fortification levels produced average recoveries in the range of 79.3-92.5% with relative standard deviations smaller than 10% for all analytes. Limits of detection (LODs) were between 0.1 and 0.5 ng/mL. Finally, the proposed method was successfully applied to a case of human poisoning.

Simultaneous determination of amitraz, chlordimeform, formetanate and metabolites in human blood by liquid chromatography tandem mass spectrometry with phospholipid‐removal pretreatment

“…This plate was introduced in blood sample preparation for the following benefits: (a) it allows direct injection of the eluate for LC–MS/MS analysis; (b) it provides excellent cleanup efficiencies to extend LC column lifetime; and (c) it makes an easy and fast preparation method to eliminate blood phospholipid (Guo et al, ; Rogatsky et al, ). In this study, it took only 4 min to clean up phospholipids in blood samples using Phree™ Phospholipid Removal Plates, which is significantly faster compared with sample preparation methods in previous blood sample analyses for determining formamidines and metabolite (Gao et al, ; Guo et al, ). MRM chromatograms of the pretreated blank blood sample show low baseline noise and clear background (shown in Supporting Information), demonstrating satisfactory removal of endogenous interfering compounds from the blood sample and good detection selectivity.…”

“…For example, as shown in Figure , the ME for DMF was 61.3% without the phospholipid‐removal step, while it was improved to 94.5% with the introduction of phospholipid‐removal pretreatment. There is a previous study on the determination of these analytes with supported liquid extraction and UHPLC–MS (Gao et al, ). The matrix effect range was 81.2–92.4%.…”

“…Gas chromatography (GC) based methods have been used, such as GC coupled with electron capture detection (Yamini, Faraji, & Ghambarian, 2015), quadrupole mass spectrometry (Yang et al, 2011) and tandem quadrupole mass spectrometry (Chamkasem, Ollis, Harmon, Lee, & Mercer, 2013). Also, several liquid chromatography (LC) based methods have been developed, including high/ultra-high performance liquid chromatography (HPLC/UPLC) in conjugation with fluorescence, ultraviolet and diode array detectors (Diserens & Henzelin, 1999;Suh et al, 2013), and mass spectrometry (MS) based detection techniques such as tandem quadrupole (Gao, Tan, & Guo, 2017;Guo, Zhang, Wang, & Zheng, 2014) and high-resolution time-of-flight MS (Gao, Guo, Zhang, & Gu, 2016). Among these determination approaches, LC-MS/MS has been proved to be an efficient and highly selective method to quantify formamidine pesticides and their metabolites in biological samples (Gao et al, 2017;Guo et al, 2014;Wu, Guo, Tan, Bu, Zhong, & Zhao, 2018).…”

Phospholipid Adsorption Polymeric Materials for Detection of Xylazine and Metabolite in Blood and Urine

“…SPE. Solid phase extraction was described in the previous publications [11,28]. A 100 L sample was mixed with 200 L of 2% formic acid and then was vortexed for 10 s and subjected to SPE.…”