Submitted to: Journal of Chromatography B
Publication Type: Peer reviewed journal
Publication Acceptance Date: 6/21/2002
Publication Date: 9/21/2002
Citation: SCHNEIDER, M.J., DONOGHUE, D.J. MULTIRESIDUE ANALYSIS OF FLUOROQUINOLONE ANTIBIOTICS IN CHICKEN TISSUE USING LIQUID CHROMATOGRAPHY-FLUORESCENCE-MASS SPECTROMETRY TISSUE USING LIQUID CHROMATOGRAPHY-FLUORESCENCE-MASS SPECTROMETRY. JOURNAL OF CHROMATOGRAPHY B. v. 780. p. 83-92. 2002. Interpretive Summary: Fluoroquinolone antibiotics are effective against a wide range of bacteria and are currently used in both medical and veterinary applications. Use of these antibiotics in food animals has generated growing concern as fluoroquinolone residues may contribute to the increased bacterial resistance to these compounds which has been recently observed. Efficient multiresidue methods are required to detect and measure levels of fluoroquinolones present in animal tissues. It is also necessary to be able to confirm the identities of the fluoroquinolones when detected. We have now developed a method which allows for the simultaneous measurement and confirmation of 8 fluoroquinolone antibiotics in chicken tissue. This approach uses liquid chromatography with fluorescence detection for measuring fluoroquinolone levels present, coupled with mass spectrometry for confirmation, taking advantage of the strengths of both techniques. With this method, we have successfully recovered, measured, and confirmed the identities of the fluoroquinolones from both fortified and incurred chicken liver and muscle samples. This efficient multiresidue approach allowing simultaneous detection, measurement, and confirmation, provides a promising tool for regulatory agencies such as FSIS.
Technical Abstract: An efficient liquid chromatographic method for the multiresidue analysis of fluoroquinolone antibiotics in chicken tissue has been developed in which quantitation using fluorescence and confirmation with mass spectrometry (to the n power) was achieved simultaneously. Using this method, 8 fluoroquinolones were analyzed in fortified samples of chicken liver and muscle tissue with recoveries at levels of 10-200 ng/ generally in the range of 60-93%, except for desethylene ciprofloxacin, which consistently gave recoveries greater than or equal to 45%. Relative standard deviations were excellent in all cases, and the limits of detection in ng/g were determined as follows in liver and (muscle): desethylene ciprofloxacin 0.3 (0.1), norfloxacin 1.2 (0.2), ciprofloxacin 2 (1.5), danofloxacin 0.2 (0.1),enrofloxacin 0.3 (0.2), orbifloxacin 1.5 (0.5), sarafloxacin 2 (0.6), difloxacin 0.3 (0.2). Confirmation was achieved by monitoring the ratios of 2 prominent product ions in MS(to the 2nd power) (desethylene ciprofloxacin) or MS(to the 3rd power) (all others). Levels of confirmation as related to ion ratio variability criteria were established. Enrofloxacin and ciprofloxacin were also determined in enrofloxacin incurred chicken liver and muscle using this method.