Development of Analytical Methods and Residual Study of Florfenicol in Animals

Florfenicol (FF), a derivative of chloramphenicol, is a broad spectrum antibiotic approved for use in livestock, poultry, and aquaculture. The drug is approved for use in animal for the treatment of bacterial infection, but the residues of FF in consumable meat pose potential risks for public health because of the increasing incidence of microbial resistance. We had developed ELISA and HPLC methods to examine the FF residue in animals, especially in ayu, tilapia, chicken, and pork. At HPLC, the LOD was 0.1 ug/mg, and the analytical average retrieve of FF in ayu’s muscle was 81%. When FF was giving to ayu in measuring medicine of hurl a time with 10, 20 and 50 mg/kg then the concentration distribution in muscle detected. The withdrawal times were 72, 96 and 96 hours, respectively. In order to raise the polyclonal antibody of FF for used in ELISA testing, we synthesize the hapten, antigen and immunogen of FF. The chemical structure of the synthetic hapten was confirmed by Nuclear Magnetic Resonance (NMR) (Brucker 500 MHz). The hapten-HRP conjugate was synthesized with the suitable hapten/HRP ratio. The cross-reactivity of the other analogue is determined by the florfenicol ELISA. The limit of detection (LOD) was 0.3 ng/mL. Cross reactivity with thiamphenicol, chloramphenicol, amoxicillin, penicillin G, chlortetracycline, tetracycline, gentamicin and streptomycin were 9.53%, 9.54%, <1%, <1%, <1%, <1%, <1%, and <1%, respectively. And that, the kit were applicable on the FF residual examination of fish. In conclusion, we have developed HPLC method and the sensitive florfenicol ELISA set for which FF could efficiently be detected.