Synthesis Of Three Molecular Imprinted Polymer Functionalized Quantum Dots And Application In Analytical Chemistry

Molecular imprinted polymer functional Quantum dots were fabricated byexcelltnt optical property of quantum dots and highly selective of molecular imprintedpolymer, as a novel nano-optical sensor which based on these nano-materials.Recently, the synthesis of molecular imprinted polymer functional Quantum dots andapplication have attracted much attention. In this dissertation, the authors principallyfocused on the synthetic routes and analytical application of molecular imprintedpolymer functionalized quantum dots. The dissertation includes four chapters, themain contents are summarized as follows:In chapter one, the basic actuality of molecular imprinted polymer functionalizedquantum dots was described. The authors summarized the progress on the synthesisand application in bioanalytical chemistry, and analyzed the deficiency on thesynthesis and application of molecular imprinted polymer functionalized quantumdots, and then put forward a preliminary plan for this dissertation.In chapter two, the authors proposed an method to elution templet in the processof synthesized QDs@MIP by ultrasonic technique for the first time, and reported“one-bath” synthesis protocol for producing silica capped CdTe quantum dots andchose4-chlorophen as the templet,3-Aminopropyl triethoxysilane as the functionalmonomers to prepared CdTe@SiO₂@MIP. Influence factors, including the elutiontime and selective of CdTe@SiO₂@MIP were investigated. AFM, IR, and powderXRD were also used to characterize CdTe@SiO₂@MIP. The data indicated that4-chlorophen can not be detected after30min ultrasonic elution andCdTe@SiO₂@MIP can selectively recognize4-chlorophen.In chapter three, ZnO@CS@MIP quantum dots were synthesized through twosteps. Firstly, ZnO@CS quantum dots were successfully pprepared by the in suitgrowing of ZnO quantum dots by self-assemble with chitosan in aqueous solution.Secondly,3-Glycidoxypropyltrimethoxysilane as the functional monomers and bovinehemoglobin as the templet, through sol-gel method ZnO@CS@MIP quantum dotswere formed. Influence factors, including the concentration and pH of buffer and absorbtion time were investigated. SEM, IR, and powder XRD were also used toidentify the characterizations of ZnO@CS@MIP. Under the optimum conditions, agood linearity was obtained between△F and the concentration of bovine hemoglobinin the range from0.50¹0μmol and a limit detection of0.21μmol.In chapter four, ZnO@CS quantum dots were synthesized by the method in thechapter three. Melamine imprinted polymers were obtained by radical precipitationpolymerization in aqueous phase, using ethylendimethacrylat （EDMA） as cross-linkerand acrylic acid （AA） as functional monomers. The ZnO@CS quantum dots wereconnected with MIPs through pepitied bond between-NH2of ZnO@CS and–COOHof MIPs by coupling agent. The core-shell structure of ZnO@PAA@MIP quantumdots was formed. The ZnO@PAA@MIP compositematerials were identified usingSEM, IR, powder XRD and TGA. Fluorescent measurement was applied to study theoptical and selective properties. The results showed that the as-preparedZnO@PAA@MIP possessed good selectivity to template molecular melamine,opticalchemistry property and very excellent thermalstability. Under the optimumconditions, this novel method can selectively and sensitively detect down to4.3×10-8mol/L of diazinon in water, and a linear relationship has been obtained covering theconcentration range of3.0×10^-73.0×10^-6mol/L. The reaction mechanism betweenmelamine and ZnO@PAA@MIP quantum dots has been primarily discussed. Theproposed method has been successfully applied to detect the content of melamine inmilk samples, and the recoveries were found to be93.5¹03.2%with standardaddition method.