Glucose Biosensor Based On Nanoau And Multi-wall Carbon Nanotubes On Au Electrodes

Diabetes was the third popular disease and there was about 50 million people who were suffering from the disease and the number was increasing by one million every year in China, so it became very important to control and cure the diabetes. Now we judged a person if she or he take the diabetes mostly according to the glucose concentration in blood, so it is imperious to construct a equipment which could estimate the glucose concentration rapidly, stability and nicety. With the development of brim and crossing subjects during recemtly years, all kinds of electrochemistry glucose biosensors were established by the teahnique combining of electrochemistry and enzyme engineering. The glucose biosensor is very popular because of its property of high selectness on enzyme catalyse as well as and high sensitivity about electricity analyse chemistry.The key factor of designing or fabricating an effective glucose biosensor is the construction of sensitive membrane of the electrode surface. Nano-crystalline particles is favorable material for constructing biosensor, due to their large surface area with diameter less than 100 nm, high surface-activity, good biocompatibility, strong adsorption and great efficiency of catalysis. In this thesis, Brief history of electrochemical glucose biosensor and working principle were illustrated. Recent development and application of immobility methods and nanomaterials on glucose biosensor were reviewed in the text, and the future of the glucose biosensor was introduced as last. And then gold electrode was regarded as basic electrode and K3Fe(CN)6 as the oxidation-reduction probe.cyclic voltammetry and linear scan voltammetry were used to investigate the assembling process and the chemical characteristics of the different modified electrode MWCNTs/CHIT and MWCNTs/AuNPs membrane electrode. The outcome of exeperiment indicated that the different modified methods both could reach the same result and meet the need about the glucose biosensor. They all owned good sensitivity and electrochemistry property and had linear relation between scan sweep and response peak current in 20 mmol/L K3Fe(CN)6+0.1 mol/L KCl system. We choose the MWCNTs/AuNPs as the working electrode because the GOD was affected by glutaraldehyde on the MWCNTs/CHIT membrane modified electrode.The relationship between response peak current and glucose concentration were studied by MWCNTs/AuNPs/GOD membrane modified electrode as working electrode and the glucose-PBS as testing solution. The experiment also were optimized including pH, fitting temperature, the dosage of GOD, the response time, disturbing experiment as well as the affected by double water. With the GOD as a model enzyme, a new glucose biosensor was fabricated. The glucose biosensor exhibited excellent performances for glucose at a scan potential (0.6--0.2V) with a high sensitivity and selectivity. In addition, the biosensor was applied in the determination of glucose in human blood and urine samples, and satisfied results were obtained. The studied results were summarized and some disadvantage and innovation Cystamine/MWCNTs/AuNPs/GOD were also introduced in the chapter. The future about the glucose biosensor and the development tendency were forecasted at last.