Preparation Of Surface-imprinted ZnO Fluorescence Sensor And Its Selective Detection Of Tetracycline Antibiotics

Tetracycline(TC)is a broad-spectrum bacteriostatic with high concentration sterilization.Because of its low price and obvious antimicrobial effect,TC has been widely used in aquaculture and veterinary drugs to promote the rapid growth of animals and prevent animal diseases.However,the excessive use of tetracycline antibiotics would lead the tetracycline residue in some meat and water exceeding seriously.Meat with excessive tetracycline will directly harm human health,while tetracycline into the water would not only endanger the ecological environment,but also endanger human health through the ecological food chain system.Fluorescence sensor-based fluorescence detection method has been used to detect various toxic and harmful substances with the advantages of simple sample processing,low detection limit,high sensitivity,short response time,strong anti-interference ability and direct observation.However,the commonly used fluorescence sensor does not have the ability of selective identification.The combination with surface molecule imprinting technique(SMIT)can give the fluorescence sensor a specific ability to identify the target molecule,and can improve the physical and chemical stability without affecting the optical performance of the fluorescence sensor.There are many methods for preparing molecularly imprinted polymers(MIPs),such as precipitation polymerization,sol-gel polymerization and atom transfer radical polymerization(ATRP)and et al.However,the relationship between morphology,structure,fluorescence properties and analytical performance of molecularly imprinted fluorescence sensors prepared by different polymerization methods have not been reported.In this paper,molecular imprinted fluorescence sensors(MIPs-ZnO NRs)were prepared by precipitation polymerization,sol-gel polymerization and atomic transfer radical polymerization(ATRP),using tetracycline(TC)as the target molecule and zinc oxide nanorodes(ZnO NRs)as solid matrix and fluorescence sensor.The morphology,structure and optical properties of MIPs-ZnO NRs were studied byTransmission electron microscopy(TEM),Fourier transform infrared spectroscopy(FT-IR),UV spectroscopy(UV-vis),X-ray diffractometer(XRD),Molecular fluorescence spectrophotometer.The fluorescence recognition and detection ability of MIPs-ZnO NRs prepared by these different polymerization methods for determining TC in the water phase were studied by the fluorescence experiments.The mainresearch results were as follows:(1)ZnO NRs were prepared by hydrothermal method,and the vinyl groups were modified on the surface of ZnO NRs by KH570.Based on the ZnO@KH570 as a fluorescent material and supporting material,the MIPs-ZnO NRs were prepared by precipitation polymerization and used for selective detection of TC in water environment.(2)PMIPs-ZnO NRs were prepared by sol-gel method using ZnO NRs as the fluorescent material and supporting material and cetyltrimethylammonium bromide(CTAB)as porogen.The selective detection of TC can be achieved by PMIPs-ZnO NRs with eluting TC and CTAB.In this experiment,PMIPs-ZnO NRs were prepared by introducing special structures(mesopores)into MIPs-Zn O NRs,and the NPMIPs-ZnO NRs were prepared without the mesopores structures.Comparing these two MIPs-ZnO NRs to summarize the role of mesopores in the selective detection of TC.(3)Brominated alkanes were modified on the surface of ZnO NRs,which were using as a fluorescent material,a supporting material and an initiator.MIPs-ZnO NRs with thin film were prepared by ATRP method and used for selective detection of TC.In this experiment,ATRP method is a new type of active radical polymerization method,which can realize the controllable thickness of the polymerization layer and help to improve the performance of selective detection of TC.