Caimao Feng

Development of an enzyme-linked immunosorbent assay for the detection of florfenicol in fish feed

Abstract A sensitive enzyme-linked immunosorbent assay (ELISA) based on monoclonal antibody was developed for routine screening of florfenicol (FF) in fish feed. FF succinate was synthesised and conjugated to human serum albumin by N-hydroxysuccinimide-activated ester method as immunogen, while it was conjugated to ovalbumin by mixed anhydride reaction as coating antigen. The ELISA for FF showed an IC50 value of 2.5 ng/mL, and negligible cross-reactivities with other amphenicol family of antibiotics. The inter-assay recoveries of FF from fortified fish feed at levels of 2–20 mg/kg ranged from 98.8 to 117.6% with coefficients of variation (CV) of 9.3–14.2%, intra-assay recoveries ranged from 102.5 to 121.2% with CV of 10.9–13.8%. The developed ELISA were then validated by liquid chromatography method and liquid chromatography–tandem mass spectrometry method, the results indicated this ELISA could be used as convenient method for detection of FF in fish feed.