Development of an Improved Method for Trace Analysis of Quinolones in Eggs of Laying Hens and Wildlife Species Using Molecularly Imprinted Polymers

A sensitive, selective, and efficient method was developed for simultaneous determination of 11 fluoroquinolones (FQs), ciprofloxacin, danofloxacin, difloxacin, enrofloxacin, flumequine, marbofloxacin, norfloxacin, ofloxacin, oxolinic acid, pipemidic acid, and sarafloxacin, in eggs by molecularly imprinted polymer (MIP) and column liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Samples were diluted with 50 mM sodium dihydrogen phosphate at pH 7.4, followed by purification with a commercial MIP (SupelMIP SPE-Fluoroquinolones). Recoveries for the 11 quinolones were in the range of 90-106% with intra- and interday relative standard deviation ranging from 1 to 6% and from 3 to 8%, respectively. Limits of detection (LODs) were 0.12-0.85 ng/g, and limits of quantification (LOQs) were 0.36 and 2.59 ng/g, whereas the decision limit (CC(α)) and detection capability (CC(β)) ranged from 0.46 to 3.35 ng/g and from 0.59 to 4.12 ng/g, respectively. The calculated relevant validation parameters are in an acceptable range and in compliance with the requirements of Commission Decision 2002/657/EC. Moreover, a comparison to two other sample treatments [solid-phase extraction (SPE) and solvent extraction] has been carried out. The method was applied to lying hens, Japanese quail, and black-headed gull eggs, in which FQs were not found. The method was also applied to study the depletion of sarafloxacin in eggs.