Discriminative determination of 15 fluoroquinolones in chicken muscle by Fe3O4@QepA based semi-homogeneous fluorescent array

The quinolone efflux pump (QepA) protein of a fluoroquinolones-resistant Escherichia coli was grafted on Fe 3 O 4 to synthesize a type of magnetic composite Fe 3 O 4 @QepA. This material was combined with 4 fluorescent tracers to develop a semi-homogeneous fluorescent array on 96-well microplate for determination of fluoroquinolones (FQs) in chicken, and the results were analyzed by using linear discriminant analysis method. Results showed this method could discriminatively determine 15 FQs at the concentration ≥10 ng/g, and could identify each drug species at the concentration ≥2 ng/g. The method exhibited satisfactory recoveries in chicken sample (61.7 %–119.8 %). The analysis results for some unknown samples were consistent with a liquid chromatography mass spectrometry method. This is the first paper reporting a semi-homogeneous fluorescent array for discriminative determination of small molecule substances, and this array can be used as an accurate tool to determine the 15 FQs in meat sample.