Affiliation: College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, P. R. China.
Florfenicol is a synthetic and broad-spectrum antibiotic and developed for veterinary use. In this study, onestep membrane-based competitive colloidal gold-based immunochromatographic formats for the rapid detection of florfenicol were developed. The quality of colloidal gold particles was monitored by UV-vis spectroscopy. For the conjugation of colloidal gold and antibody, 24 μg/mL of antibody was confirmed to the optimal amount for stabilization of colloidal gold. With the prepared colloidal gold immunochromatography test strip was determined the standard florfenicol solution. The results demonstrated a detection limit of florfenicol was approximately 1.0 μg/mL. The study showed that the strip had a high sensitivity to florfenicol and without cross-reaction for other antibiotics. The results of 80 animal samples tests confirmed that 0 sample was higher than the detection limits by liquid chromatography-mass spectrometry (LC-MS). There was evidence to suggest that colloidal gold particles and GAB gold-labeled antibody were synthesized successfully. The prepared colloidal gold immunochromatography strip could be used for preliminary screening of florfenicol.