title: Analysis of anticoagulant rodenticide residues in Microtus arvalis tissues by liquid chromatography with diode array, fluorescence and mass spectrometry detection.
abstract: We describe here a fast and selective analytical method to determine the levels of four anticoagulant rodenticides (chlorophacinone, bromadiolone, brodifacoum and difenacoum) in animal tissues by liquid chromatography (LC) using different detection methods: fluorescence (FLD), diode array (DAD) and electrospray ionization-mass spectrometry (ESI-MS). Rodenticides were extracted from freeze-dried and homogenized tissue samples (liver, intestine and muscle) that had been obtained from the common vole (Microtus arvalis). These samples were diluted in 5 mL of methanol, the solution was shaken and centrifuged, and the supernatant was removed and evaporated to dryness. The residue was reconstituted in 1 mL of methanol (liver samples) or 1 mL of the mobile phase (muscle and intestine samples), and injected onto an LC-DAD-FLD-MS system coupled to electrospray ionization (ESI) in negative mode. After conducting an LC optimization study, we selected a Gemini 5 μm C18 column, a mobile phase composed of a mixture of 30 mM ammonium formate in water and methanol (26:74, v/v), and we used an isocratic elution mode. The method was fully validated and shown to be selective, precise, accurate, and linear in the range from ~5μg/kg (ESI-MS) or ~50 μg/kg (DAD-FLD) to 10,000 μg/kg, depending on the compound analyzed. Recoveries ranged from 82% to 103%, while the limits of detection and quantification ranged from 9-89 μg/kg (FLD-DAD) and 0.6-4.6 μg/kg (ESI-MS). This method was successfully used to simultaneously measure the aforementioned compounds in M. arvalis tissues.
authors.affiliation: I.U. CINQUIMA, Analytical Chemistry Group, University of Valladolid, 47011 Valladolid, Spain.
authors.forename: Alma M
authors.initials: AM
authors.lastname: Hernández
authors.forename: José
authors.initials: J
authors.lastname: Bernal
authors.forename: José L
authors.initials: JL
authors.lastname: Bernal
authors.forename: María T
authors.initials: MT
authors.lastname: Martín
authors.forename: Constantino
authors.initials: C
authors.lastname: Caminero
authors.forename: María J
authors.initials: MJ
authors.lastname: Nozal
mesh_terms: D000818:Animals; D000925:Anticoagulants / Q000032:analysis* / Q000493:pharmacokinetics; D003411:Arvicolinae; D002853:Chromatography, Liquid / Q000379:methods*; D016018:Least-Squares Analysis; D057230:Limit of Detection; D013058:Mass Spectrometry / Q000379:methods*; D015203:Reproducibility of Results; D012378:Rodenticides / Q000032:analysis* / Q000493:pharmacokinetics; D013050:Spectrometry, Fluorescence; D014018:Tissue Distribution
chemical_list: D000925:Anticoagulants; D012378:Rodenticides