title: Simultaneous determination of amitraz, chlordimeform, formetanate and their main metabolites in human urine by high performance liquid chromatography-tandem mass spectrometry.
abstract: A rapid, simple and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for simultaneous determination of amitraz, chlordimeform, formetanate and their main metabolites, N-(2,4-dimethylphenyl)-N-methyl-formamidine (DMPF), 2,4-dimethylformamidine (DMF), 2,4-dimethylaniline (DMA), 4-chloro-2-methylaniline and 3-hydroxyacetanilide in human urine. The urine samples were mixed with buffer solutions (pH 8) and subsequently cleaned up by solid supported liquid/liquid extraction (SLE). The target analytes were efficiently separated with a Waters Atlantis T3 column (150mm×4.6mm, 5μm), ionized with electrospray ion source in positive mode, and quantitatively determined by tandem mass spectrometry in the multiple reaction monitoring (MRM) mode. In order to minimize matrix effects, the matrix-matched calibration curves of eight analytes were adopted with correlation coefficients (R2) above 0.99. The method were further validated by determining the limits of detection (LODs, 0.3-0.6ng/mL), the limits of quantitation (LOQs, 1.0-2.0ng/mL) and recoveries (89.1%-108.4%) with intra-day and inter-day relative standard deviation (RSD, <11%). The established method was applied and demonstrated in a real case by assaying a urine sample from a female poisoned by formetanate. The achieved results proved this method to be rapid, sensitive and accurate for simultaneous quantitation of eight analytes in human urine for intended forensic cases of human poisoning.
authors.affiliation: Chongqing Key Lab of Catalysis & Functional Organic Molecules, Chongqing Technology and Business University, Chongqing 400067, China; School of Resources and Environment, Chongqing Technology and Business University, Chongqing 400067, China.
authors.forename: Xue
authors.initials: X
authors.lastname: Gao
authors.affiliation: Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors.forename: Yanglan
authors.initials: Y
authors.lastname: Tan
authors.affiliation: Chongqing Institute of Forensic Science, Chongqing 400021, China. Electronic address: hao.guo1982@hotmail.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Guo
mesh_terms: D058647:Adrenergic alpha-2 Receptor Agonists / Q000378:metabolism / Q000652:urine*; D002219:Carbamates / Q000378:metabolism / Q000652:urine*; D002742:Chlorphenamidine / Q000378:metabolism / Q000652:urine*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005260:Female; D006801:Humans; D007306:Insecticides / Q000378:metabolism / Q000652:urine*; D057230:Limit of Detection; D053719:Tandem Mass Spectrometry / Q000379:methods; D014052:Toluidines / Q000378:metabolism / Q000652:urine*
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D002219:Carbamates; D007306:Insecticides; D014052:Toluidines; C014983:amitraz; C100163:formetanate; D002742:Chlorphenamidine
keywords: Formamidine pesticides; HPLC–MS/MS; Human urine; Metabolites; Solid supported liquid/liquid extraction (SLE)