| Abstract: | Fluoroquinolones are effective antimicrobial agents, but their residues in food may cause serious health issues. Hence, it is necessary to develop a rapid and simple assay for fluoroquinolones. In this study, monoclonal antibodies against ciprofloxacin with broad specificity to fluoroquinolones were prepared. The newly developed magnetic particle-based competitive enzyme immunoassay was performed in a homogeneous sample, and ciprofloxacin was quantitatively detected in the range of 0.3–24.3 ng mL?1. The IC50 and LOD values of the method were 2.27 ng mL?1 and 0.25 ng mL?1. In chicken muscle, the recoveries of spiked ciprofloxacin at 8, 20, and 40 ng mL?1 were all higher than 79%. Additionally, the performance of the developed magnetic particle-based immunoassay exhibited an excellent correlation with commercial ELISA kits (r = 0.997). The anti-ciprofloxacin monoclonal antibodies provided high cross-reactivity with eight fluoroquinolones analogues: enrofloxacin (110.1%), sarafloxacin (99.7%), difloxacin (90.2%), danofloxacin (89.8%), norfloxacin (110.3%), lomefloxacin (65.2%), ofloxacin (75.1%), and flumequine (45.0%). This protocol provides an alternative immunoassay for ciprofloxacin with the advantages of simple separation, a homogeneous reaction, rapid detection (within 30 min), and stable results. Furthermore, it may be employed for the rapid general determination of fluoroquinolones in animal products. |
