The Preparation And Bioelectrochemical Research Of Cerasome And Cerasome-based Functional Nanomaterial

The development of the third generation electrochemical biosensor has aroused great interest recently.However,it is usually difficult for the redox proteins to directly exchange electrons with electrode surface due to several factors,such as the deeply embedded electroactive center,unfavorable orientation and denaturation of proteins.Therefore,it is important to develop novel biocompatible materials for the fabrication of modified electrode to promote the direct electrochemical reactions of the immobilized protien.Herein,biocompatible Cerasome and its functionalized composite,which was quantum dot(QDs)-Cerasome nanocomposite were designed and synthesized for the constructionof the third generation electrochemical biosensors.Based on the above mentioned,the content of the thesis was summarized as follow:1.Novel biocompatible Cerasome,which exhibited good stability and solubility in aqueous solution have been sunthesized.TEM?SEM?AFM?FTIR were utilized to characterize the morphology and structure of the as prepared Cerasome.In addition,Glucose oxidase(GOD)was immobilized onto the Cerasome modified glassy carbon(GC)electrode by physically embedding method.Cyclic voltammograms was then utilized to characterize the electrochemical behavior of Cerasome/GOD/GC modified electrode.It has been found that such modified electrode can not only realize the direct electron transfer between GOD and electrode,but also exhibit excellent electrocatalytic activity toward the oxidation of glucose.2.Water soluble nanoparticles CdTe QDs with positive charge was firstly prepared and characterized by UV-Vis?FL?XRD?XPS measurements.Then,the biocompatible and fluoresence nanocomposite,which was QDs-Cerasome was fabricated by the electrostatic interaction between the positively charged QDs and negatively charged Cerasome.The interaction between redox protein---(Hb)and the nanocomposite was investigated.It has been found that the obvious quench of the fluoresence of QDs-Cerasome can be observed after the immobilization of Hb onto the nanocomposite.Moreover,the as prepared Hb-QDs-Cerasome/GC modified electrode can greatly enhanced the direct electron transfer between Hb and electrode.Based on the direct electrochemistry of the immoblized Hb,the modified electtrodeexhibited excellent catalytic performance for the detection of hydrogen peroxide.Compared with Hb-Cerasome/GC and Hb-QDs/GC modified electrode,Hb-QDs-Cerasome/GC modified electrode exhibited wider detection range and higher sensitivity.