Spatial Control of Bio-Materials by Suspended Carbon Nanotubes

本项目的目的分为两个主题：(1)碳纳米管网络对包括半导体、碳纳米管互连和生物功能元件在内的纳米集成器件的控制。(2)碳纳米管对生物分子在碳纳米管上的吸附机理研究。为此，我们研究了碳纳米管三维网络的制备技术和吸附在碳纳米管表面的生物分子(如蛋白质和DNA)的表征。在碳纳米管网络中，我们开发了一种在金属催化剂辅助下的化学气相沉积接枝技术。在这种技术中，碳纳米管是从沉积在馅饼生长的悬浮碳纳米管上的催化剂颗粒中生长出来的。利用这种技术，可以制备出三维碳纳米管网络。用…观察了碳纳米管的接枝生长机理，发现碳纳米管的接枝是有效的由于催化剂颗粒和生长的碳纳米管被固定在一个自由空间中，所以更多的是一种透射电子显微镜。碳纳米管片是以多孔二氧化硅薄膜作为催化剂颗粒的支撑材料，通过化学气相沉积法制备的。DNA通过化学键固定在碳纳米管片上。用荧光分子标记DNA，在荧光显微镜下观察。我们成功地观察到DNA在碳纳米管片上的吸附和DNA的杂交。蛋白质分子的吸附性质在碳纳米管在生物技术和医学上的应用中是重要的。我们将碳纳米管应用于血浆交换中的吸附材料，以去除导致肝脏疾病的胆红素。用红外光谱分析了其吸附行为。我们发现白蛋白和亲和素等蛋白质分子可以高效地吸附在碳纳米管表面。综上所述，我们构建了三维碳纳米管网络，并将其应用于蛋白质和DNA分子的固定化。较少

The purpose of this project is classified into two themes:(1) Control of carbon nanotube networks toward nano-integrated devices including semiconductors, carbon nanotube interconnections and bio-functional components.(2) Investigation of adsorption mechanism of bio-molecules onto carbon nanotubes toward bio- and medical-application of carbon nanotubes.For these goals, we have studied fabrication techniques of carbon nanotube three-dimensional networks and characterization of bio-molecules, such as proteins and DNAs, adsorbed on carbon nanotube surfaces.In carbon nanotube networks, we have developed a grafting technique using a chemical vapor deposition assisted with metal catalysts. In this technique, carbon nanotubes are grown from catalyst particle deposited on the pie-grown suspended carbon nanotubes. Using this technique, a three-dimensional carbon nanotube networks can be fabricated. It was found that the carbon nanotube grafting is powerful to observe the growth mechanism using … More a transmission electron microscopy because the catalyst particles and grown carbon nanotubes are fixed in a free space.Carbon nanotube sheets were fabricated by the chemical vapor deposition using a porous silica film as a supporting material for catalyst particles. DNAs were immobilized on the grown carbon nanotube sheets through chemical bonds. DNAs were labeled with fluorescent molecules and observed using fluorescence microscopy. We succeeded to observe adsorption of DNAs onto the carbon nanotube sheets and hybridization of DNAs.Adsorption properties of protein molecules are important in application of carbon nanotubes to bio-technology and medicine. We applied carbon nanotubes to adsorption materials in plasma exchange to remove bilirubin which causes liver disease. The adsorption behavior was analyzed by infrared vibration spectroscopy. We found that protein molecules, such as albumin and avidin, are adsorbed on carbon nanotube surfaces at a high efficiency.In conclusion, we have fabricated three-dimensional carbon nanotube networks and applied them to immobilization of protein and DNA molecules. Less