Study On Glucose Biosensor Based On Biomaterials As Matrixes

Chapter 1:The biosensor of concept, structure, features, applications are reviewed, and then the glucose biosensor of construction, principles, classification and fabrication are presented.Chapter 2:A glucose biosensor using an enzyme-immobilized onion primary cuticula membrane and oxygen electrode for glucose determination has been fabricated. Glucose oxidase was immobilized on an onion primary cuticula membrane with glutaraldehyde as a cross-linking agent and chitosan as a embedding agent. The effect of amount of enzyme, glutaraldehyde concentration, pH, phosphate buffer concentration and temperature on the response of the glucose biosensor has been studied in detail. This biosensor showed a wide linear relationship with a concentration range of 20μM-1.1 mM, a fast response time (75 s), good repeatability (2.8%, n=10) and satisfactory reproducibility (2.26%, n=3). The biosensor retained 90% of its initial response after 3 months at 25℃. The proposed biosensor method has been successfully applied to the determination of glucose concentration in human blood serum and obtained results were agreement with the colorimetric assay kit.Chapter 3:A glucose biosensor based on the swim bladder immobilized glucose oxidase has been developed. The glucose concentration was quantified by the decrease of dissolved oxygen. In addition, the effects of enzyme loading, pH, buffer concentration and interference studied in detail. When the enzyme concentration was 2.0%, pH was 7.0, and the buffer concentration was 100mM, the biosensor showed a maximum response. The biosensor showed a wide linear relationship with a concentration range of 16μM-1.2 mM, a fast response time (70 s), good repeatability (2.50%, n=10) and satisfactory reproducibility (1.15%, n=3). The biosensor retained 88.5% of its initial response after 3 months, and the immobilized enzyme retained its 95% activity after 200 times used. The proposed biosensor method was successfully applied to the determination of glucose concentration in human blood serum and the results were agreement with that obtained from a colorimetric assay kit method.Chapter 4:A glucose biosensor using an onion inner epdermis membrane and oxygen electrode has been fabricated. Glucose oxidase was immobilized on an onion inner epdermis membrane with glutaraldehyde as a cross-linking agent. The effect of amount of enzyme, glutaraldehyde concentration, pH, phosphate buffer concentration and temperature on the response of the glucose biosensor has been studied in detail.This biosensor showed a wide linear relationship with a concentration range of 24μM-1.2 mM, a fast response time (70 s), but a short self-life.Chapter 5:A simple glucose biosensor consisting of an onion primary cuticula membrane immobilized with Au nanoparticles/glucose oxidase and an oxygen sensor has been fabricated, and the experiment condition are preliminary discussed.