Construction Of A Single Nanowire Sensor For Intracellular Glucose Detection

Glucose,as an indispensable nutrient,plays significant roles in many physiological processes,and glucose metabolism disorder may cause a variety of diseases.The body promotes target cells to uptake or release glucose through hormone regulation mechanism to maintain normal blood glucose levels.Once losing control,such regulation could only be sustained by some specific drugs.Given that intracellular glucose is closely related to glucose regulation,metabolism and disease states,real-time monitoring of intracellular glucose levels can provide some indispensable information in glucose-involved physiological or pathological process,which is particularly important to better understand the underlying mechanisms at the single cell level.Electrochemical glucose sensors are widely used for the detection of glucose,and have obvious advantages on fast,real-time and quantitative analysis.However,intracellular glucose detection cannot be achieved by these sensors owing to their large size and consequent low spatial resolution.Ultramicroelectrodes have made great progress in the analysis of various substances at the single cell and subcellular level due to their high spatial and temporal resolution.By immobilization of GOD onto the microelectrode or nanoelectrode,the spatial resolution of electrochemical glucose sensor has been efficiently improved for intracellular glucose detection.Nevertheless,it is still a huge challenge in the preparation of high performance nanosensors modified with GOD for real-time monitoring of glucose levels and its fluctuations inside a single cell.In view of the above research background,this paper aimed to develop a glucose nanowire sensor with excellent mechanical properties,high sensitivity and high spatial and temporal resolution for electrochemical detection of intracellular glucose.The thesis will be introduced through the following two parts:1.The construction of glucose nanowire sensor.Platinum nanoparticles was deposited on the surface of the core-shell nanowire electrode developed in our laboratory,followed by modification of glucose oxidase on the surface by covalent cross-linking to prepared glucose nanowire sensor with excellent electrochemical response to glucose.This allows the real-time monitoring of the intracellular glucose level.2.The insulin antagonist cell model was constructed by high insulin incubation.The glucose nanowire sensor was used to investigate the changes of intracellular glucose levels before and after insulin resistance.On this basis,it was quantitatively monitored for the change of intracellular glucose induced by the new hypoglycemic agent human fibroblast growth factor 1(FGF1),and the mechanism of promoting glucose uptake by the cells to alleviate insulin antagonism was explored,revealing the potential applications in blood glucose regulation.In summary,we provide a general strategy for the preparation of single nanowire electrochemical sensors,providing a universal method for the detection of intracellular non-electrochemically active molecules.Meanwhile,intracellular glucose detection is expected to be an important tool in the study of glucose-related physiological pathology,and provides data support.