Development Of Enzyme-linked Immunosorbent Assay (ELISA) For Detection Of Enrofloxacin, Sudan Red And Chloramphenicol In Food Samples

With the development of the economy, the living standard is improving, and the requirement of the animal derived food is increasing. In order to increase the output of the animal derived food and make the food beautiful to look at, some veterinary drugs were added by lawless persons. But most of the drugs were banned to be used in food processing because of their carcinogenicity or other side effects. In order to ensure the safety of the foodstuff, many detection methods were developed to detect the drug residue, such as LC-MS, GC-MS and HPLC. Because of their fund and time consumption, these methods were hard to be used widespread. Enzyme-linked immunosorbent assay (ELISA) was a rapid detection method to detect drug residue with a high sensitivity and low detection limit. And magnetic affinity immunoassay (MAIA) was a method developed on the basement of the ELISA with a higher sensitivity. The perpurse of the thesis was to develop some ELISA methods to detect the enrofloxacin and sudan red in food and make sure which MAIA method was suitable to make kits.Enrofloxacin was detected by the ELISA kits with an IC50 of 3.237 ng.mL"1 in buffer. And the detection limit was 0.42 ng.mL-1. The aim of this thesis was to detect the enrofloxacin residue in animal derived food. The experiment proved that the enrofloxacin residues were more in liver than in muscle, and the most of the animal derived food on sale were injected with enrofloxacin.Sudan red was a kind of aze dyes which was banned to be used in food. The immunogen was synthesized by glutaraldehyde. And the monoclonal antibody was obtained by cell culture and monoclone. The antibody showed high sensitivity with an IC50 of 1.7 ng.mL-1, and the range of the working curve was from 0.5 ng.mL-1 to 13.5 ng.mL-1. The specificity of the antibody was evaluated by the cross-reactivity of the antibody with sudan red and para red. The detection limit in chilli oil and chilli jam was 9.0 ng.mL-1 and 19.6 ng.mL-1, respectively. The recovery rates were in the range of 80%-110%, and the variation were both less than 20%.MAIA was based on ELISA with higher sensitivity. Compared with the ELISA (IC50=0.72 ng.mL"1), the sensitivity of the MAIA to chloramphenicol was 0.05 ng.mL-1 in MethodⅠand 0.4 ng.mL-1 in MethodⅡThe experiments showed that the sensitivity of MethodⅠwas higher than MethodⅡwhile MethodⅡwas suitable to be used in kits production because of its convenience.In this thesis, we obtained monoclonal antibody of sudan red and developed the detection methods to the drugs. Based on this thesis, some ELISA kits can be produced.