Study On Synthesis And Application Of Molecularly Imprinted Materials For Quinolones And Xanthine Analogues

Synthesis imprinted monolithic column and water-compatible imprinted polymers is the most active hotspot of molecular imprinted technique(MIT). Fluoroquinolones and alkaloids were selected as the research object with the suppot of MIT.Synthesis, characteristics, and recognition menchnism of the theophylline imprinted monolithic column were investigated Theophylline imprinted monolithic columns were designed by an in-situ thermal-initiated copolymerization technique. The chromatographic conditions, binding capacity, morphological characteristics and thermodynamic characteristic were evaluated. The present monolithic MIP columns were successfully applied for the quantitative determination of caffeine and theophylline in different kinds of green tea.Water-compatible imprinted polymers were Synthesized and be successfully applied to solid-phase extraction. Water-compatible imprinted polymers with high selectivity to quinolones in polar condition were prepared in methanol-water system using ofloxacin and enrofloxcin as template respectively. The effect of polymerization conditions and characteristics of the MIPs such as binding capacity and chromatography characteristics were evaluated. These polymers show high affinity to quinolones in aqueous environment and were successfully applied as special sorbents for selective solid-phase extraction of quinolones from environmental and biological samples. Furthermore, the matrix interferences origing from complex samples could be effectively eliminated while the analytes were selectively extrated and enriched. The molecular recognition mechanisms of the obtained MIPs were investigated by the molecular simulation using HyperChem V6.0.1 software and PM3 semi-experimentalism compute model, and then were experimental validation with UV and infrared spectrogram as well as 1H NMR.A new selective sample cleanup procedure, molecularly-imprinted matrix solid-phase dispersion (MI-MSPD) was developed for the extraction of fluoroquinolones from different biological samples. By using C18 and MIPs as different dispersants, the extraction and separation conditions of quinolones in biological samples were investigated and optimized. The MIPs applied as the selective dispersant of MSPD could selectively extracted fluoroquinolones from complicated sample matrix, while interferences originated from biological matrices were eliminated simultaneously. The proposed MIP-MSPD method only requires a small amount of sample (0.1mL) and uses aqueous solutions for clean-up step, which significant reduction in both sample size and solvent consumption. The extracts were clean enough to inject directly into HPLC for further chromatographic analysis. The developed method is simple and sensitive, and can be used as an alternative tool to the existing HPLC methods for analyzing the residues of fluoroquinolones in biological samples. Furthermore, to improve the affinity and recognization in water solution, the preparation conditions of the MIP in aqeous environment was further investigated. The technique of MIP-MSPD have potential application to many fileds.