| Nanotechnology and biotechnology are two key technologies of the 21st century. Herein, nanobiosensing technology is one of the cutting edges and becomes an emerging area nowadays.Biosensors have developed to be a frontier and newly-interdisciplinary including chemistry, biology, medical science and electronics since the development of the first glucose biosensor in 1967. Due to its simplicity, high sensitivity and potential ability for real-time and on-site analysis, biosensor has been widely applied in various fields including clinical diagnosis, environment monitoring, food control and industrial process, and so on.Nanotechnology involves the study, manipulation, creation and use of materials, devices and systems typically with dimensions smaller than 100 nm. Nanomaterials, or matrices with at least one of their dimensions ranging in scale from 1 to 100 nm, display unique physical and chemical features because of the quantum size effect, mini size effect, surface effect and macro-quantum tunnel effect. Nanotechnology is revolutionizing the development of biosensors. Sensitivity and other attributes of biosensors can be improved by using nanomaterials in their construction. On the other hand, use of nanomaterials in biosensors allows the apllication of many new signal transduction technologies in their manufacture. Attributed to their submicron size, nanosensors, nanoprobes and other nanosystems are playing important roles in the fields of chemical and biological analysis, and enable rapid analysis of multiple substances in vivo.This dissertation focuses on 1) fabricating novel biosensors based on newnanomaterials and nanostructures, and integrated them with microdialysis, flow injection analysis, etc. 2) establishing the bases for application of them to biological and clinical diagnose. We are adhering to an organic combination of nanotechnology, biosensing technology and clinical researches. The details are given as follows:Chapter One: PrefaceA critical review with regard to the biosensor and nanotechnology is given. Then the application of nanotechnology into biosensors was highlighted. After introducing nanomaterials, the physical and other attributes of biosensors can be improved. Moreover, analyzing multiple components in vivo is becoming available.Chapter Two: A Novel Glucose Biosensor Based on Palladium Nanoparticles and Its Application in Detection of Glucose Level in UrineA novel glucose biosensor was constructed by electrodeposition of highly dispersed palladium (Pd) nanoparticles on a glassy carbon electrode (GCE). Atomic force microscopy (AFM) was applied to characterize its surface morphology. Electrodeposited Pd nanoparticles exhibited efficiently electrocatalytic oxidation for hydrogen peroxide (H2O2) with relatively high sensitivity and stability, which was studied by CV technique and Raman spectroscopy, respectively. The GC/Pd/GOD/Nafion system allowed a low working potential of +0.3 V (vs. SCE). Its signal current was linearly related to the glucose concentration in the range of 1.0×1.0-6 1.0×1.0-4 mol·L-1 with a detection limit of 5.0×1.0-7 mol·L-1. The sensor required no special pretreatment to suppress interference from urate and L-ascorbate. It was successfully used in detection of glucose level in human urine samples with high stability, sensitivity and anti-poisoning ability.Chapter Three: Immobilization of Uricase on ZnO Nanorods for a Reagentless Uric Acid BiosensorA reagentless uric acid (UA) biosensor based on uricase immobilized on ZnO nanorods was developed. Direct electrochemistry and thermal stability of immobilizeduricase were studied. The ZnO nanorods achieved the direct electron transfer of uricase and showed excellent thermal stability, and anti-interference ability. This sensor depicted an electrocatalytic activity to the oxidation of uric acid without the presence of an electron mediator. The electrocatalytic response showed a linear dependence on the uric acid concentration ranging from 5.0×10-6 to 1.0×10-3 mol·L-1 with a detection limit of...
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