The Preparation And Bioelectrochemical Application Of Polymeric Ionic Liquid Modified Meroporous Composite

Based on the direct electrochemical transfer between the redox enzyme or protein and the electrode,the third generation electrochemical biosensor can acheive the analysis of various important substance with nice sensitivity and high efficiency.It is known that the most important thing for the construction of the third generation of electrochemical biosensor lies in the selection of suitable electrode material with better biocompatiblility and good conductivity.Being a new type of mesoporous silicate,siliceous mesostructured Cellular Foams(MCF)has a highly three-dimensional ordered meso-struture,large pore volume and specific area and,narrow pore-size distribution,and good biocompatibility.Because of its unique structure and property,MCF has been widely used in various fields.However,due to the inherent low conductivity,it is not suitable for MCF utilized as electrode material for the construction of electrochemical biosensors.Polymeric ionic liquid is new type of polymer synthesized via the polymerization of ionic liquid monomors.Such polymer can exhibit the properties of ionic liquid and organic polymer,such as high conductivity and thermostability.In this thesis,polymeric ionic liquid was served as modyfier to functionalize MCF.The as prepared polymeric ionic liquid modified mesoporous silicate can exhibit synergistic effects of each component material,and thereby enhance the performance of electrochemical biosensor.Based on the above mentioned,the research work of the dissertation are summarized as follows:1.Firstly,MCF was prepared based on a ’soft template’ hydrothermal synthesis method.After that,the thiol functional group was modified onto MCF via a covalent method.Then,the novel Poly(ViEtIm+Br-)-MCF composite was synthesized by"thiol-ene" click chemistry.The as prepared Poly(ViEtIm+Br-)-MCF was characteristiced by TT-IR,zeta potential,XRD,XPS and N2 adsorption-desorption measurements.Redox enzyme GOD was further immobilized into the Poly(ViEtIm+Br-)-MCF to form GOD/Poly(ViEtIm+Br-)-MCF/GC electrode.The immobilized GOD can not only acheive the direct electron transfer on GC electrode,but also exhibited good electrochemical performance toward the electrocatalytic detection of glucose.2.Based on the anion-exchange reaction of the modified polymeric ionic liquid on MCF,AuCl4-was immobilized onto the surface of mesoporous silicate.Then,after the in-situ reduction process,Au nanoparticles can be introduced onto MCF to form AuNPs/Poly(ViEtIm+Br-)-MCF.The morphology and structure of the as prepared mesoporous composite was characteristiced by Uv-vis,XRD,TEM,N2 adsorption-desorption measurements.Because of the conductivity and biocompability of the functionalized Au nanoparticle,the direct electron transfer of immobilized GOD on AuNPs/Poly(ViEtIm+Br-)-MCF/GC electrode can be greatly enhanced,thus making the modified electrode exhibiting better performance toward the detection of glucose,such as wide linear range(1-14.7 mM)and low detection limit(0.33 mM).