Dot-immunogold filtration assay for rapid screening of three fluoroquinolones

Abstract

A dot-immunogold filtration assay (DIGFA) was described for simultaneous screening of three fluoroquinolones (FQs): enrofloxacin (ENR), ciprofloxacin (CIP) and norfloxacin (NOR). Colloidal gold particles were used as visible labels, and anti-ENR polyclonal antibodies from mice and rabbits were exploited for gold labelling and membrane coating, respectively. Several parameters affecting DIGFA were optimised, and the operation was validated with pure buffer matrix and spiked eel samples, respectively. The detection limits in eel samples were estimated to be about 20 μg kg 1 for ENR and CIP, and 50 μg kg 1 for NOR. With pretreated nitrocellulose membranes, the determination could be completed within 30 minutes, and the results could be read just by the naked eye without the help of any equipment. © 2009 Taylor & Francis.