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Anti-coagulant rodenticides (ARs) are commonly utilized for controlling rodent populations; however, non-target companion and wildlife animals are also exposed. A method was developed for quantitation of seven ARs (chlorophacinone, coumachlor, bromadiolone, brodifacoum, difethialone, diphacinone and warfarin) and dicoumarol (a naturally occurring anti-coagulant) in animal serum. Analytes were extracted with 10% (v/v) acetone in methanol and analyzed by reverse phase high-performance liquid chromatography-tandem mass spectrometry using electrospray ionization (negative mode) combined with multiple reaction monitoring. In-house method validation in the originating laboratory using non-blinded samples revealed method limits of quantitation at 2.5 ng/mL for all analytes. The inter-assay accuracy ranged from 99% to 104%, and the relative standard deviation ranged from 3.5% to 20.5%. Method performance was then verified in the originating laboratory during an exercise organized by an independent party using blinded samples. The method was successfully transferred to two naïve laboratories and further evaluated for reproducibility among three laboratories by means of Horwitz ratio (HorRat(R)) values. Such extensive validation provides a high degree of confidence that the method is rugged, robust, and will perform as expected if used by others in the future., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

In this work, a method for the extraction of dicoumarol from plant sample utilizing selective adsorbent based on molecularly imprinted polymer was developed. Molecularly imprinted polymer (MIP) was synthesized by bulk polymerization, and on the surface of magnetic particles using dicoumarol as a template, methacrylic acid as functional monomer, chloroform as a porogen, and ethyleneglycol dimethacrylate as a cross-linker. Prepared polymeric materials were evaluated on the base of capacity, selectivity, and morphology. The maximal specific adsoption capacities of the sorbents were 45 μg (for bulk MIP) and 36 μg (for MIP on the magnetic particles) of dicoumarol per 1 g of polymer. An efficiencies of sorption processes of dicoumarol on prepared sorbents were evaluated under various conditions (type of sample solvent, pH, types of washing and elution solvents). The MIP based sorbents were used for solid phase extraction of dicoumarol. Applicability of MIP-SPE coupled to HPLC-DAD was tested for the selective extraction of dicoumarol from sample of sweet clover. The method was linear over concentration range from 1 to 100 μg mL -1 (the correlation coefficient 0.9984) with limit of detection 0.2 μg mL -1 . Accuracy of the method was assessed for spiked sample at three concentration levels and recovery values were higher than 84% with relative standard deviation lower than 3.2%., (Copyright © 2018 Elsevier B.V. All rights reserved.)