New Type Of Carbon Nanomaterials And Its Application In Biosensors

Nanomaterials were honored as the most important materials in present world. Carbon nanomaterials was a member of the new type of nanomaterials, which had excellent characters in physics, materials and chemistry, and had promising application in these areas. Now many methods of synthesis this kind of carbon nanomaterials had discovered by analyst to their mounts of effective research, such as graphite arc discharge, pulsed laser deposition and chemical vapor deposition (Chemical Vapor catalytic Deposition). The as synthesized materials showed different feature like amorphous carbon, carbon nanoparticles, carbon nanosphere, carbon nanotube particles, carbon nanotube and catalytic particles. The most standing out material was spiral net or tubular carbon nanotube. Because of its light and hexagonal structure, addition to novel electromagnetical, chemical, mechanical character, it was combined with other materials and then widely used as nanoscale hydrogen storage materials, miniature electronic components used in field emission electron source (such as nanowire,nanoelectronic switch, nanorod, memory cell), large capacity electric double layer capacitor materials, subminiature accessory (micro gears, molecular coils, piston, pump), radar absorbing material used in stealth aircraft, special optical material, nonlinear optical material, soft magnetic materials, molecular vehicle, biological sensing materials and so on. However, Carbon composite material was another kind of carbon nanomaterial, especially the shell-core carbon coated nanocomposite, which was an ideal composite showed character of both matrix and dispersion. It was widely used in hydrogen storage, catalysis and medical domain. Biosensors were kinds of easy to take and convenient analytical device, which were composed of biomolecules like enzyme, liposome, bacterium, yeast, antibody or antigen, and so on. So looking for new biosensors material to make simple and practical biosensors is a popular question in science research area now. According to recent reports, we do the following three aspects in this paper. (1) We fabricated a novel amperometric nonenzymatic glucose sensor based on PtIr naniparticles descorated on carbon nanotube (PtIr/CNT hybrids) and applied it to nonenzymatic glucose detection. Its electrochemical behavior towards the oxidation of glucose was compared with Pt naniparticles deposited on carbon nanotube (Pt/CNT hybrids) prepared with a similar procedure. In PtIr/CNT hybrids, PtIr nanoparticles were homogeneously dispersed on carbon nanotubes with an average diameter of2.0nm. And its size can be controlled by tuning the Pt/Ir ratio. In contrast, Pt nanopartcles are unevenly distributed on carbon nanotubes with an average diameter of5.0nm. The PtIr/CNT hybrid modified electrode show a higher electroactive surface area, and displays greatly enhanced electrocatalytic activity towards glucose oxidation. Chronoamperometry was applied in glucose detection in0.2M Phosphate buff solution (pH7.4) containing0.15M NaCl. The effect of the size of PtIr nanoparticles and the applied potential was investigated. The as-prepared PtIr/CNT hybrid based glucose sensor displays significantly higher sensitivity, lower detection limit and wider linear range than that of Pt/CNT modified electrode. Moreover, Ir addition in Pt catalysts enabled amperometric glucose detection with longer stability and insignificant interference from ascorbic acid, uric acid and4-acetamidophenol. These results indicate that the PtIr/CNT hybrid is a promising candidate in the development of highly sensitive and selective nonenzymatic glucose sensors.(2) Firstly we fabricated TeNW@C core-shell nanocomposite with the help of glucose and PVP as reductant and stabilizing agent. Then the TeNW@C core-shell nanocomposite was converted to PtNW@C core-shell nanowire with noble metal salt H2PtCl6. The morphology of Pt/C core-shell nanowire was imaged by TEM. We also discussed its electrochemical behavior to H2O2detection. The results indicate that Pt/C core-shell nanowire is a promising material to H2O2detection, which act out highly sensitive, good stability and fast detection to H2O2.(3) Recently, noble metal nanoclusters were preferred by science researcher. These clusters possess particularly small size, exhibit a strong fluorescence emission and excellent photostability. Especially, protein-stabilized Au nanocluster attracted more attention because of its easy making, red emission and biocompatibility. Then at last of this paper, we synthesized red emission Au nanocluster with BSA, and applied it to detect alcohol. We took consideration of temperatures, pH and biological interference in experiment. To our result, the protein-stabilized Au nanocluster is a perfect material to alcohol fast detection.