Construction And Performance Of The Platinum-based Nonenzymatic Glucose Sensor

Recently,diabetes has become a generally epidemic disease,which is harmful to human's health,the number of patients is continuously increasing,timely detecting the level of blood glucose is particularly important to diabetes.Therefore,looking for a simple,effective and sensitive means of detecting blood glucose has important value of application.Although,the methods of detecting blood glucose have chromatography,spectrometry and colorimetry,these methods are inconvenient to carry and test,which is limited in practical application.In order to solve this problem,researchers studied the electrochemical glucose sensor(GS).Electrochemical GS has received wide attention,which is an effective method to measure blood glucose.Electrochemical GS includes enzymatic glucose sensor(EGS)and non-enzymatic glucose sensor(NEGS),enzyme is easily deactivated in the process of immobilization and vulnerable to the influence of external environment,which limits the application of EGS on clinic.Without the interference of external condition,NEGS has overcome the shortcomings of EGS,which has aroused people's great research interest.Nanomaterial has very large specific surface area,excellent electron transfer rate,good electrocatalytic activity and biological compatibility,which can improve the sensitivity,linear detection range,selectivity,reproducibility and stability of sensor.In this paper,the platinum based NEGS was constructed using platinum based catalyst as the material of modified electrode of sensor,the linear detection range,sensitivity,detection limit,anti interference,repeatability and stability were investigated using cyclic voltammetry(CV)and time current method.This paper is divided into six chapters,each chapter is introduced as follows:In chapter one,the research progress of GS and the significance and main research content were recommend in detail.The progress of GS and research status of electrode materials of NEGS were introduced.In chapter two,the experimental reagents and instruments,preparation of reduction of graphene oxide(RGO),preparation of Pt based catalysts,construction of NEGS,characterization techniques of materials and sensor were briefly introduced.In chapter three,the graphite oxide(GO)was prepared by the modified Hummer method,at the same time,the RGO were synthesized,which used ethanol(EtOH),1-propanol(PrOH),1-butanol(BuOH)and phenyl carbinol(PhOH)as a reducing agent respectively.The influence of different kind of alcohol on the chemical and structural properties of the RGO were investigated systemically.X-ray Riffraction(XRD),Fourier Transform Infrared Spectroscopy(FTIR),UV-Vis Spectrophotometer(UV),X-ray Photoelectron Spectroscopy(XPS),Scanning Electron Microscope(SEM),Transmission Electron Microscopy(TEM)and CV characterization methods indicated that the RGO reduced by PhOH had the best performance.Meanwhile,the reducibility of EtOH?PrOH and BuOH decreased with the elongation of carbon chain,which might be explained by the lowed ability for hydrogen donation and the increase of steric hindrance.Through changing the kind of alcohol could get the different reduction degree of RGO,which achieved the controllable preparation of RGO.In chapter four,the RGO and carbon nanotube(CNT)composite was prepared,which used chemical reduction method with PhOH as reducing agent.Then a series of Pt/RGO,Pt/CNT and Pt/RGO-CNT nanomaterials were prepared by impregnation reduction method with RGO,CNT and RGO-CNT as carriers and applied in NEGS.The characterization of XRD,TEM and Electrochemical method showed that the RGO-CNT composite and Pt nanoparticles were formed.In addition,electrochemical test showed that Pt/RGO-CNT had higher electrocatalytic activity than Pt/RGO and Pt/CNT.The NEGS constructed with Pt/RGO-CNT/GC electrode had good repeatability,selectivity and stability.The linear range of the sensor for detecting glucose was 1-15 mM,the sensitivity was 24.28 ?Acm-2 mM-1(R=0.999),the detection limit was 0.379 ?M.In chapter five,a series of PtxPdy/RGO-CNT nanomaterials were prepared by doping Pd in the preparation of Pt/RGO-CNT nanomaterial,and the NEGS was constructed at the same time.TEM,EDS and XRD characterizations confirmed the formation of PtPd alloy.Electrochemical method showed that the catalytic activity of PtxPdy/RGO-CNT to glucose was higher than Pt/RGO-CNT and Pd/RGO-CNT,when the quality ratio of Pt and Pd was 3:1,the alloy catalyst had the highest catalytic activity,the NEGS constructed with Pt3Pd1/RGO-CNT/GC electrode showed the linear range of detecting glucose was 1-16 mM,the sensitivity was 42.49 ?Acm-2 mM-1(R=0.9996),the detection limit was 0.239 ?M and the sensor had good repeatability,selectivity and stability.Compared with the NEGS constructed with Pt/RGO-CNT/GC electrode had higher sensitivity and lower detection limit,which was expected to be applied in the detecting blood sugar on clinic.In chapter six,the paper was summarized,the development prospect of glucose sensor was proposed simultaneously.