Surveillance improves control of Salmonella infections.

Surveillance improves control of Salmonella infections.

A liquid chromatographic method was developed for the analysis of indandione and 4-hydroxycoumarin anticoagulant rodenticides in blood serum and liver. The method enabled the measurement of serum and liver concentrations of eight anticoagulant rodenticides: brodifacoum, bromadiolone, chlorophacinone, coumafuryl, coumatetralyl, diphacinone, difenacoum, and warfarin. Anticoagulants were extracted from serum and liver with acetonitrile. Extracts were applied to solid-phase extraction columns, which contained mixed packings. Column eluates were evaporated to dryness, reconstituted, and subjected to reversed-phase liquid chromatography. Hydroxycoumarins were detected by fluorescence at an excitation wavelength of 318 nm and an emission wavelength of 390 nm. Indandiones were detected by UV absorption at 285 nm. Extraction efficiencies of greater than 75% for serum and greater than 69% for liver were obtained. The within-run precision (CV) ranged from 2.4 to 8.6% for serum and 2.6 to 8.7% for liver. The between-run precision (CV) ranged from 1.5 to 12.2% for serum and from 2.1 to 11.8% for liver. Hydroxycoumarin rodenticides were detected at 1 ng/mL of serum and 1 ng/g of liver. Indandiones were detected at 10 ng/mL of serum and 10 ng/g of liver.

No abstract

A sensitive liquid chromatographic method was developed for the analysis of 4-hydroxycoumarin anticoagulant rodenticides in blood serum. The method can simultaneously measure the serum levels of five anticoagulant rodenticides: brodifacoum, bromadiolone, coumatetralyl, difenacoum, and warfarin. Serum proteins are precipitated with acetonitrile and the supernatant is mixed with ethyl ether. The organic phase is separated, evaporated to dryness, and the residue subjected to chromatographic analysis. The anticoagulants are separated by reversed-phase gradient chromatography with fluorescence detection at an excitation wavelength of 318 nm and emission wavelength of 390 nm. Extraction efficiencies of 68.1 to 98.2% were obtained. The within-run precision (CV) ranged from 2.19 to 3.79% and the between-run precision (CV) from 3.72 to 9.57%. The anticoagulants can be quantitated at serum levels of 10 to 20 ng/mL.