Study On Preparation Of Fluoroquinolones Molecularly Imprinted Materials And Their Properties

In this research,four kinds of molecular imprinted polymers(MIPs)were prepared using gatifloxacin(GTFX)and ofloxacin(OFLX)as template molecules,respectively.The adsorption properties of the MIPs were investigated by UV spectrophotometer.As adsorbents,combined with high performance liquid chromatography(HPLC)analysis,the MIPs were successfully applied to extract and enrich GTFX and OFLX in milk,lake and bovine serum samples.The main work of the thesis is as follows:1.Based on monodisperse crosslinked PGMA/EDMA microsphere,using GTFX as template molecule,methacrylic acid(MAA)as functional monomer,the surface molecularly imprinted polymers(MIP/PGMA/EDMA)were prepared in the mixed solution of methanol-acetonitrile(1:1,V/V).The interaction between GTFX and MAA was studied by UV spectrophotometer.The adsorption capacity and selective adsorption ability of MIP/PGMA/EDMA to GTFX were investigated by static adsorption experiment,and the maximum apparent adsorption capacities and dissociation constants were calculated by Scatchard plot.The adsorption rate of MIP/PGMA/EDMA to GTFX was investigated by dynamic adsorption experiment,and the dynamic adsorption behavior was analyzed by kinetic equation.As solid-phase extraction(SPE)packing(MIP-SPE),the reusability of MIP/PGMA/EDMA was investigated.A method based on MIP-SPE assisted by HPLC was developed for separation and determination of GTFX in milk and lake samples.2.First,we synthesized Fe3O4 nanoparticles and Fe3O4@ SiO2 by coprecipitation method and sol-gel technology,respectively.Next,we modified of double bond group onto Fe3O4@SiO2.Finally,we synthesized magnetic molecularly imprinted polymers(M-MIPs)for GTFX on the surface of Fe3O4@SiO2-MPS.The magnetic nanoparticles were investigated by means of transmission electron microscopy(TEM),X-ray diffraction(XRD)and vibrating sample magnetometer(VSM).The adsorption porperties of M-MIPs to GTFX were investigated by binding experiments.The resulted M-MIPs were employed as adsorbent coupled with HPLC for separation and determination of GTFX in milk samples.3.In this part,we studied the binding of template molecule OFLX with functional monomers MAA and 4-vinyl pyridine(4-VP)by UV spectrophotometry,to determine the better functional monomer.Then,we synthetized three kinds of molecularly imprinted polymers(MIPs)and non-imprinted polymers(NIPs)with different proportions of OFLX and the better functional monomer,to determine the optimum preparation proportion by comparing adsorption capacity and imprinting factor.The restricted access media-molecularly imprinted polymers(RAM-MIPs)for OFLX were prepared by precipitation polymerization in the 50 mL mixed solution of methanol-water(9:1,V/V).Selective recognition experiment was performed by using GTFX,enrofloxacin(ENRO)and sulfamerazine(SMR)as competitive compounds.Bovine serum albumin(BSA)was selected as model protein to investigate the exclusion ability of RAM-MIPs to protein.Coupling with HPLC analysis,this work provided an approach for purification,extraction and detection of OFLX in milk samples.4.A new restricted access materials combined to molecularly imprinted polymers(Sil-RAM-MIPs)were prepared via surface-initiated atom transfer radical polymerization(SI-ATRP)based on 5.0 μm silica.OFLX,MAA and glycidyl methacrylate(GMA)were employed as template molecule,functional monomer and hydrophilic functional monomer,respectively.The binding properties of Sil-RAM-MIPs to OFLX were evaluated by Scatchard model.The adsorption behavior of Sil-RAM-MIPs to OFLX was analyzed by Langmuir and Freundlich isothermal models.The exclusion ability of Sil-RAM-MIPs to BSA was investigated with SPE technology.This work provided an approach for analysis of OFLX in bovine serum samples.