Establishment And Application Of Three Methods For Detection Of Chloramphenicol Residues

Chloramphenicol is a broad-spectrum antibacterial drug,which can inhibit a variety of bacteria.It has been widely used to control diseases in animals and humans.As it is widely used in foods of animal origin,residues of chloramphenicol will be potentially harmful to human health.The purpose of this thesis is to synthesize specific molecular imprinted polymers for chloramphenicol,and to establish direct competitive chemiluminescence,chemiluminescence resonance energy transfer and direct competitive fluorescence methods for the detection of chloramphenicol residues in foods of animal origin.The unique structure in the molecular structure of chloramphenicol was found to be nitrobenzene by YASARA software simulation.Three kinds of specific molecularly imprinted polymers to chloramphenicol were synthesized using nitrobenzene as the template molecule.First,a direct competitive chemiluminescence method was developed by coating the synthesized molecularly imprinted polymer particles on a microtiter plate as recognition elements.The results show that the limit of detection of this method was 5.0 pg/g,and the recoveries were in the range of 71.5%～94.4%in pork,chicken,and fish samples.Furthermore,the coated plates can be reused four times.Secondly,a type of molecularly imprinted microsphere was polymerized on the surface of magnetic graphene to synthesize a novel composite.This composite was used as a recognition reagent and energy acceptor to develop the chemiluminescence resonance energy transfer method.The limit of detection for chloramphenicol in pork,chicken,and fish samples was 2.0 pg/g,and the recoveries were in the range of 69.5%～97.3%.The graphene microsphere can be reused 30 times.Finally,a molecularly imprinted microsphere-based direct competitive fluorescence method was established.It is only necessary to add the sample solution and fluorescent marker into the well for competition,without the addition of other reagents,and can be directly detected.The results show that the limit of detection of this method was 0.06 ng/g,and the recoveries were in the range of 67.5%～96.2%.The coated plates could be reused 5 times.In this study,all the three methods based on the molecularly imprinted polymers are rapid,simple,sensitive,accurate and renewable,which could be used as a routine screening tool for the detection of chloramphenicol residues in meat.It is of great significance to protect the safety of meat and maintain the health of consumers.