title: Simultaneous determination of neonicotinoid insecticides in human serum and urine using diatomaceous earth-assisted extraction and liquid chromatography-tandem mass spectrometry.
abstract: A rapid and sensitive analytical method was developed for simultaneous determination of eight neonicotinoid insecticides (acetamiprid, clothianidin, dinotefuran, flonicamid, imidacloprid, nitenpyram, thiacloprid and thiamethoxam) and three specific metabolites of acetamiprid (N-desmethylacetamiprid, 5-(N-acetyl-N-methylaminomethyl)-2-chloropyridine and 5-(N-acetylaminomethyl)-2-chloropyridine) in human serum and urine. A diatomaceous earth-assisted extraction using Extrelut NT3 column with chloroform/2-propanol (3:1, v/v) as eluent was selected for the single step cleanup procedure for all the target compounds. Qualitative and quantitative analyses were conducted by liquid chromatography-tandem mass spectrometry with multiple reaction monitoring mode. The limits of detection and the limits of quantification of eleven compounds were in the ranges of 0.1-0.2ng/mL and 0.5-10ng/mL for serum, 0.1-1ng/mL and 1-10ng/mL for urine, respectively. The extraction recoveries were between 80.9% and 101.8% for serum samples, 91.9% and 106% for urine samples. The intra-day RSDs and the inter-day RSDs were less than 11.5% and 13.2% for serum, less than 8.3% and 8.8% for urine. The proposed procedure will be suitable for forensic investigations of human poisoning cases with neonicotinoid insecticides. This is the first report of simultaneous determination of eight neonicotinoids in serum and urine samples.
authors.affiliation: National Research Institute of Police Science, 6-3-1, Kashiwa-no-ha, Kashiwa, Chiba 277-0882, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Yamamuro
authors.affiliation: National Research Institute of Police Science, 6-3-1, Kashiwa-no-ha, Kashiwa, Chiba 277-0882, Japan. Electronic address: ohta@nrips.go.jp.
authors.forename: Hikoto
authors.initials: H
authors.lastname: Ohta
authors.affiliation: Forensic Science Laboratory, Hokkaido Prefectural Police H.Q., N2 W7, Chuo-ku, Sapporo, Hokkaido 060-8520, Japan.
authors.forename: Mika
authors.initials: M
authors.lastname: Aoyama
authors.affiliation: National Research Institute of Police Science, 6-3-1, Kashiwa-no-ha, Kashiwa, Chiba 277-0882, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Watanabe
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D007692:Diatomaceous Earth / Q000737:chemistry; D006801:Humans; D007306:Insecticides / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification / Q000652:urine; D057230:Limit of Detection; D016014:Linear Models; D009574:Nitro Compounds / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification / Q000652:urine; D011725:Pyridines / Q000097:blood* / Q000737:chemistry / Q000302:isolation & purification / Q000652:urine; D015203:Reproducibility of Results; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D007306:Insecticides; D009574:Nitro Compounds; D011725:Pyridines; D007692:Diatomaceous Earth
keywords: Diatomaceous earth column; Isotope dilution; Liquid chromatography–tandem mass spectrometry; Neonicotinoids