A RAPID SPECTROFLUOROMETRIC SCREENING METHOD FOR ENROFLOXACIN IN CHICKEN MUSCLE

Authors: Chen, Guoying; Schneider, Marilyn

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/14/2003
Publication Date: 5/21/2003
Citation: CHEN, G., SCHNEIDER, M.J. A RAPID SPECTROFLUOROMETRIC SCREENING METHOD FOR ENROFLOXACIN IN CHICKEN MUSCLE. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY. 2003. v. 51. p. 3249-3253.

Interpretive Summary: Enrofloxacin (ENRO) is a fluoroquinolone antibiotic approved by the U.S. Food and Drug Administration (FDA) for use in the chicken industry due to its efficacy in treating a variety of bacterial infections. Its widespread veterinary use may, however, contribute to the emergence of drug-resistant organisms. Considering the number of chickens consumed in the U.S., an efficient screening method is in demand. A typical separation of ENRO from muscle matrix proves to be a challenging task that requires multiple steps. Here we develop a simple spectrofluorometric method in which a single-step extraction was performed without further clean up. Linear calibration was obtained from a series of ENRO fortified chicken samples. Eighteen chicken breast samples from three producers were tested and the results showed background signal levels below the approved tolerance level. The measurements were reproducible with the major variability coming from the different chicken samples. ENRO incurred samples were examined using this approach, and the results agreed well with those obtained from more extensive separation followed by high-performance liquid chromatography. Based on this investigation, a reliable high-throughput screening method for ENRO in chicken tissue is proposed for potential use by regulatory agencies such as FSIS.

Technical Abstract: A simple spectrofluorometric method was developed for screening enrofloxacin (ENRO) in chicken muscle in which a single-step extraction was performed without further clean up. Among extraction media investigated acidic acetonitrile gave the best results. Following centrifugation the supernatants were excited at 324 nm and the emission measured at 442 nm. Eighteen chicken breast samples from three producers were tested and the results showed background signal levels below 300 ÿg/kg, the FDA approved tolerance level. The calibration curve revealed a satisfactory linear relationship (R2 = 0.9991) over a range of 0 - 700 ÿg/kg ENRO in fortified chicken breast. ENRO incurred samples were examined using this approach, and the results agreed well with those obtained from more extensive separation followed by high-performance liquid chromatography. The method proved reproducible. Screening of ENRO at the tolerance level can be accomplished with a threshold limit set at 3ÿ. Based on this investigation, a high-throughput screening method for ENRO in chicken tissue is proposed.