Preparation Of Surface Molecular Imprinting Polymer Onto Magnetic Yeast Composites And Selective Recognition To Iodixanol

With the extensiuelyuse of contrast media in diagnostic and interventionalprocedures,In the clinic, radiological （X-ray） examination is widely used as a reli-ablemethod to help diagnose cardiovascular disease by imaging certain disorders. Contrastagents has Existence of adverse renal events to the kidneys, Contras-tmedia inducednephropathy（CIN）has been ranked No.2among a drug-induced acute renal failure，which is just after aminoglycoside antibiotics.Contrast-in-duced nephropathy hasbecome the third common cause of hospital acquired acuterenal failure.This paper choose the biomedical molecule iodixanol （soldcommercially underthe trade name Visipaque） as an object of study，which has been widely used as awater-soluble, iodinated X-ray contrast agent[1]. Using atom transfer radicalpolymerization （ATRP）prepared a quick, cheap, selective adsorbents based onmolecularly imprinted and magnetic separation technology, and using the adsorbentsto the Adsorption of iodixanol in water, so that not only have better extractionefficiency, but also to avoid removing considerable amounts of certain bloodconstituents which should preferably be retained in.In this thesis，iodixanol was been chosen as an object of study because of it’srepresentative and extensive contrast agent,and the preparation adsorbent by atomtransfer radical polymerization of surface-imprinted core-shell magnetic aboutiodixanol. First, the magnetic yeast composites （mag–yeast） were successfullyprepared by coating the chito-san layer containing APTES-fixed Fe₃O₄nanoparticlesonto the surface of the yeast. then, using2-bromoisobutyryl bromide modified themagnetic yeast composites，and The mag–yeast–Br was collected （R-X） as aninitiator，PMDETA as a ligand, a transition metal CuCl as a catalyst，Iodixanol（template）, methacrylic acid （MAA）（monomer） and EGDMA （crosslinker） wereweighed and added to ethanol/deionized （DI） water （5:1） solvent mixture, MMIPsmicrospheres were synthesized by atom transfer radical polymerization （ATRP） thatcontrollable the molecular weight of molecularly imprinted polymer （MMIPs）.Compared to the magnetic non-imprinted polymers （MNIPs）, MMIPs showedremarkable affinity and selectivity to iodixanol, what’s more，it’s easy to reach themagnetic separation under an extermal magnetic field. the structure of the productwere characterized by scanning electron microscopy（SEM） and Fourier transforminfrared（FT-IR） analysis. Through the study of experiment combining with the balance and the theoreticalanalysis, this paper obtained following performance:（1）The optimization of MMIPs adsorbing the iodixanol: pH=7, the dosage ofMMIPs is10g/L.（2）The adsorption kinetics experiment of MMIPs indicate: MMIPs adsorbing theiodixanol can reach the balance quickly, the time can be set as1h.Through dynamicquasi level model and dynamics quasi level2model fitting results show that theprocess of MMIPs adsorbing iodixanol is more adapt to the dynamics quasi lebel2and fitting coefficient R2is close to1.Besides,on the basis of the intramoleculardiffusion model and the theory of Weber and Morris,deducing that the process ofadsorption is controled by the external diffusion and particle internal diffusion.（3）The adsorption isotherm experiment of MMIPs to iodixianol show that：Freundlich and Langmuir adsorption model both can indicate the adsorption ofiodixianol by MIPs preferably.Using the Scatchard model fitting,known that MMIPshas specificity and nonspecific adsorption.And isotherm calculated thermodynamicparameters show that adsorption is spontaneous, exothermal physical adsorptionprocess.