Confirmation of Quinolone Antibacterials in Porcine Meat and Kidneys by Gas Chromatography/Mass Spectrometry Using Selected Ion Monitoring

Abstract

A gas chromatographic/mass spectrometric method (GC/MS) using selected ion monitoring (SIM) was developed for the determination of oxolinic acid, ofloxacin, enrofloxacin, and danafloxacin in porcine meat and kidneys. Quinolone antibacterials were extracted with 0.3% metaphosphoric acid-acetonitrile (6: 4) followed by a Sep-Pak PS-2 cleanup procedure. After evaporation, the residue was dissolved in methanol and reduced with sodium tetrahydroborate treated with 0.1N HC1. Quinolone derivatives were extracted by a Sep-Pak PS-2 from the reaction mixture and analyzed by GC/MS (SIM). Average recoveries of the drugs from tissues were in the ranges of 80.8-90.5% in meat and 82.3-88.6% in kidneys. Detection limits were 0.01μg/g for oxolinic acid, ofloxacin, and enrofloxacin and 0.02μg/g for danofloxacin.