Abstract: A rapid and sensitive colloidal gold immunochromatographic assay based on a monoclonal antibody,which could detect 11 fluoroquinolones(FQs) was developed. The monoclonal antibody was labeled with 20 nm gold particles as the detection reagent which was immobilized on glass fiber, and norfloxacin- ovalbumin was blotted on the test line while a sheep anti-mouse antibody was used on the control line combined on nitrocellose. The detection limits of the strip in pork and shrimp samples were 30 ng/g for ciprofloxacin, enrofloxacin, ofloxacin and 100 ng/g for norfloxacin, pefloxacin, enoxacin, marbofloxacin, lomefloxacin, danofloxacin, sarafloxacin and difloxacin. The whole process involved sample preparation and detection could be finished in less than 20 minutes. The results demonstrated that the method could be used as a screening tool for the determination of 11 FQs residues in large amount of pork and shrimp samples on site.

Key words: fluoroquinolones; colloidal gold; immunochromatography; rapid detection of multiple residues