The Research Of Glucose Oxidation And Coating Process Based On The Photophysical And Catalytic Properties Of Gold Nanorods

Gold nanomaterials have attracted many researchers’ attention in the area of bio sensor and bio image because of their unique property of plasmon dependent optical response characteristic.Gold nanorods(Au NRs),as one kind of gold nanomaterial,show a highly dependence between their optical physical property and their size,shape,and composition.Besides,Au NRs show two strong localized plasmon resonance absorption peaks within the visible to the infrared range.One of them is transverse surface plasmon resonance(TSPR),and another is localized surface plasmon resonance(LSPR).The later one is depend on the surrounding medium and the change of rods’aspect ratio.The position of LSPR would change correspondingly based on the variation of surrounding medium or rod’s aspect ratio.In this way,detecting the change of gold nanorods’morphology and the reaction process are achievable by detecting the change of their LSPR peak position.Hydrogen peroxide is a substance radical metabolism,and it shows strong oxidizing property under acidic condition.Due to this strong oxidizing property,hydrogen peroxide is able to etch gold nanorods,and alter the optical plasmon absorption characteristics of gold nanorods by changing their morphology features.Therefore,by establishing the relationship between hydrogen peroxide and the change of gold nanorods’ LSPR characteristics,an effective detection method of detecting biomolecules which generate hydrogen peroxide could be created.Glucose oxidase is a kind of biological protein molecules,and it can catalyze glucose to generate hydrogen peroxide.Glucose oxidase can be attached to gold nanorods,and then catalyze glucose to generate hydrogen peroxide.As we mentioned before,hydrogen peroxide can etch gold nanorods.Therefore,a new glucose detection method could be established by detecting the corrosion extent of gold nanorods.Besides the unique LSPR sensing property,the catalytic property of gold nanorods has widely attracted people’s attention as well.New chemicals can be formed under the catalysis of gold nanorods.Generally,it needs extreme reaction conditions for small glucose molecules to polymerize into glucan.However,specific gold nanorods can exhibit strong catalytic ability,and provide glucose a possibility to polymerize into glucan even under the room temperature.This provides significant value for further study of glucan-coated metal biological applications.There main aspects of work have been done as follows:(1)Studying the growth process of gold nanorods.Preparing several Au NRs samples with different length by controlling the growth conditions.Studying the impact of hydrogen peroxide on the structure and properties of gold nanorods.(2)Treating glucose and glucose oxidase as research models,studying the effect between the reaction products and the structure and properties of Au NRs.Establishing the relationship between the glucose and the property of gold nanorods,which thereby provides a simple means of detecting glucose.(3)Studying the reaction mechanism between molecules based on the catalytic property of gold nanorods is a key research project.According to the research reports,gold nanorods show different catalytic properties when the growth states are different.Gold nanorods exhibit strong catalytic property when the aspect ratio of rod is lower than 2.Based on this theory,the third part of the work is catalyzing glucose into glucan by using specific gold nanorods,and synthesizing Au NRs@Glucan composite materials.It provides important foundation for this new kind of composite material in the area of biological application.