Preparation And Application Of Surface Molecularly Imprinted Polymers Functionalized By Fluorescence Or Magnetism

As people change their attitude to food consumption toward quality style, food safety is increasingly concerned by society, and the issue of veterinary drug residue is one of the focal points. Efficient and reliable analysis method is the guarantee for supervision over the use of veterinary drugs. Due to complex substrate environment and trace levels of the concentrations, not only the sensitive detection method was needed, but also effective sample pretreatment method. Based on molecular imprinting technology, in this thesis fluorescence analyzing method and magnetic solid phase extraction method were used for the analysis of veterinary drug residues in milk, respectively.1. A functional monomer with a fluorescence signal belonging to the ultraviolet region was used to fabricate UV-fluorescence surface molecularly imprinted polymers for the first time, which has fluorescence quenching response to sulfamethyldiazine. The successful material preparation was proved by electron microscopy, FT-IR and fluorescence characterization. After template molecules were adsorbed by imprinted material, UV absorption signal of template can convert to fluorescence quenching signal of imprinted material. The linear relationship between the degree of fluorescence quenching and sulfamethyldiazine concentration in the system can be established by Stern-Volmer quenching equation, and the method was initially applied to the detection of sulfamethyldiazine in milk matrix with simple and convenient features, the linear range is between 0.5 and 20 μM, and the limit of detection was 98.4 nM.2. Using both conventional free radical polymerization (RP) and atom transfer radical polymerization (ATRP) methods prepared two sets of enrofloxacin surface imprinted material having the magnetic separation function respectively, and the preparation conditions of magnetic carrier were optimized. The successful material preparation were proved by electron microscopy, FT-IR and VSM characterization. Such magnetic nanomaterials coated imprinted polymers can quickly be separated from the substrate under magnetic field. After optimizing the adsorption conditions, the adsorption performance of two materials were compared, and the MIPs prepeared by ATRP shows better selectivity, which was coupling with HPLC to analyze fluoroquinolones residues in milk samples with satisfactory results.