title: A validated LC-MS-MS method for simultaneous identification and quantitation of rodenticides in blood.
abstract: A rapid, highly sensitive and specific analytical method for the extraction, identification and quantification of nine rodenticides from whole blood has been developed and validated. Commercially available rodenticides in Australia include coumatetralyl, warfarin, brodifacoum, bromadiolone, difenacoum, flocoumafen, difethialone, diphacinone and chlorophacinone. A Waters ACQUITY UPLC TQD system operating in multiple reaction monitoring mode was used to conduct the analysis. Two different ionization techniques, ES+ and ES-, were examined to achieve optimal sensitivity and selectivity resulting in detection by MS-MS using electrospray ionization in positive mode for difenacoum and brodifacoum and in negative mode for all other analytes. All analytes were extracted from 200 µL of whole blood with ethylacetate and separated on a Waters ACQUITY UPLC BEH-C18 column using gradient elution. Ammonium acetate (10 mM, pH 7.5) and methanol were used as mobile phases with a total run time of 8 min. Recoveries were between 70 and 105% with limits of detection ranging from 0.5 to 1 ng/mL. The limit of quantitation was 2 ng/mL for all analytes. Calibration curves were linear within the range 2-200 ng/mL for all analytes with the coefficient of determination ≥0.98. The application of the proposed method using liquid-liquid extraction in a series of clinical investigations and forensic toxicological analyses was successful.
authors.affiliation: Forensic and Analytical Science Service, NSW Health Pathology, Sydney, Australia sergei.bidny@health.nsw.gov.au.
authors.forename: Sergei
authors.initials: S
authors.lastname: Bidny
authors.affiliation: Forensic and Analytical Science Service, NSW Health Pathology, Sydney, Australia.
authors.forename: Kim
authors.initials: K
authors.lastname: Gago
authors.affiliation: Forensic and Analytical Science Service, NSW Health Pathology, Sydney, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: David
authors.affiliation: Forensic and Analytical Science Service, NSW Health Pathology, Sydney, Australia.
authors.forename: Thanh
authors.initials: T
authors.lastname: Duong
authors.affiliation: Forensic and Analytical Science Service, NSW Health Pathology, Sydney, Australia.
authors.forename: Desdemona
authors.initials: D
authors.lastname: Albertyn
authors.affiliation: Clinical Pharmacology and Toxicology, Westmead Hospital, Sydney, Australia Discipline of Emergency Medicine, Sydney Medical School, Sydney, Australia.
authors.forename: Naren
authors.initials: N
authors.lastname: Gunja
mesh_terms: D001344:Autopsy; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000592:standards; D053593:Forensic Toxicology / Q000379:methods* / Q000592:standards; D006801:Humans; D057230:Limit of Detection; D012015:Reference Standards; D015203:Reproducibility of Results; D012378:Rodenticides / Q000097:blood*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000592:standards; D053719:Tandem Mass Spectrometry / Q000592:standards
chemical_list: D012378:Rodenticides