MULTIRESIDUE ANALYSIS OF 9 ANTICOAGULANT RODENTICIDES IN SERUM

A rapid procedure was developed for the determination of nine anticoag ulant rodenticides in animal serum by high-performance liquid chromato graphy (HPLC) with a fluorescence and photodiode array detector (DAD). The anticoagulants coumafuryl, pindone, warfarin, coumachlor, diphaci none, chlorphacinone, bromadialone, brodifacoum, and difethialone were extracted and quantitated simultaneously with this method. Anticoagul ants were extracted at pH 5.5 with 5% (v/v) ethanol in ethyl acetate a nd 1% (w/v) trichloroacetic acid. Sample extracts were subjected to a cleanup on a Florisil solid-phase extraction (SPE) column. Separation was performed with a reversed phase amine-deactivated C-18 column with a gradient of phosphate buffer, acetonitrile, and methanal. The eluen t was monitored with the fluorescence detection at an excitation wavel ength of 310 nm and an emission wavelength of 390 nm, and the photodio de array detection was set to 325 nm. Recoveries from spiked serum sam ples at ranges of 0.004-1 ppm were between 73 and 105%. The precision (CV) data range was between 1.6 and 15.6%. Detection limits were betwe en 0.005 and 0.002 ppm for the fluorescence detection and between 0.02 0 and 0.050 ppm for the photodiode array detection at 325 nm.