Preparation, Characterisation And Application Of Molecularly Imprinted Polymers Toward Kresoxim-methyl

Molecularly imprinted polymers(MIPs) are novel adsorption materials with high specificrecognition for target molecules in complex samples. Kresoxim-methyl had been appliedwidely for it’s high activity, broad-spectrum and low toxicity. People have focused moreattentions on the residue problems because of the increasing amount of usage. We applied theMIPs in the pretreatment of pesticide residue analysis. It would be a new, simple and effectivemethod for kresoxim-methyl’s enrichment and purification. The main work of the thesis includethe following parts:1,Molecular imprinted polymers(MIPs) were synthesized using kresoxim-methyl astemplate, methacrylic acid(MAA) as monomer, ethylene glycol dimethacrylate (EDMA) ascrosslinker and2,2-azobisisobutyronitrile(AIBN) as initiator by bulk and precipitationpolymerization. The preparation conditions of molecularly imprinted polymers, such as solventsand its volume, the amount of EDMA and Polymerization temperature were optimized in orderto obtain desired uniform microspheres. We used UV spectrum to choose the appropriatefunctional monomer and then detected the characteristics and specific surface area of MIPs byLaser Particle Sizer. Adsorption ability of the polymers was estimated by binding experiment.Itwas demonstrated that MIPs had a certain adsorption capacity for kresoxim-methyl relative tothe blank imprinted polymers. Scatchard analysis indicated that the selective adsorption siteswas uniform and the maximum binding was97.11mg/g. FT-IR analysis revealed the formationof MIP and the chemical interaction with templates. SEM illustrated the shape and size of MIPswas uniform and spherical distribution.2, The loading,washing and elute procedures for the SPE cartridge for kresoxim-methylwere established with MIPs as the adsorbent. We concluded that using hexane as loading solvent,higher washing efficiency was obtained when using the mixture of hexane:methylene chloride(4:1v:v), The optimized elution condition was ACN:acetic acid(9:1v:v). Application ofMI-SPE to soil and plant samples of potato. The recoveries experiment showed that the MI-SPEpossessed high performance for kresoxim-methyl’s enrichment and purification in soil and plantsamples. In addition，the MI-SPE was better than Florisil for purification and save much moresolvents.