磁性奈米碳管的製備及其應用

Abstract

在本研究分為四大部份，第一部份為在823 K下通入乙炔，由於氧化鋁的催化性質，會使乙炔在陽極處理氧化鋁 (Anodic Alumminum oxide，AAO)的孔道中進行裂解環化反應，而可以得到石墨層排列為平行碳管長軸且與AAO孔洞大小相似的奈米碳管，且其石墨層間距約為0.343 nm，長度為數個μm。 第二部份以C@AAO為模板，利用氨水還原化學劑量比的兩價與三價的鐵離子水溶液的反應來製備磁性奈米碳管。藉由穿透式電子顯微鏡、X-Ray繞射儀，以及化學分析電子能譜儀等鑑定了我們所合成的磁性奈米碳管為Fe3O4@CNT的結構。 第三部份以磁性奈米碳管表面以聚丙烯酸修飾成帶負電性之探針，可用於吸附水中微量的正電性樣品。如利用蛋白質具有不同等電點的特性，可在不同pH值的環境下使其帶有不同的正負電性，可藉著pH值之改變而利用聚丙烯酸修飾的磁性奈米碳管篩選濃縮特定的目標胜肽或蛋白質，並以UV/Vis吸收圖譜估計磁性奈米碳管萃取分析物數量。 第四部份嘗試以磁性奈米碳管做為表面輔助雷射脫附游離質譜法基質的可能性，應用於SALDI定性分析胜肽之用途。

The thesis are divided into four parts. In the first part, acetylene was decomposed inside the anodic aluminum oxide membranes (AAO) channels to form carbon nanotube (CNT) at 823 K. The CNT diameter varied with the diameter of the AAO channels. The graphite layers of carbon nanotubes were parallel to the tube axis, and the d–spacing of the graphite layers was estimated to be 0.343 nm and length was about several μm. In the second part, iron oxide filled CNTs arrays were synthesized via anodic aluminum oxide (AAO) template-assisted aqueous solution method, which involved an aqueous ammonia solution in the reduction of ferrous and ferric ions. From many characterizations such as TEM, XRD, and XPS, we confirm these magnetic carbon nanotubes to Fe3O4@CNT magnetite phase. In the third part, poly(acrylic acid) treated magnetic carbon nanotubes were employed as affinity probes to selectively concentrate traces of positively charged analytes from sample solutions through electrostatic interactions. Because proteins have their unique isoelectric points (pI), by varying the values of pH of the same solution, specific proteins can be concentrated selectively on the surface of the poly(acrylic acid) treated magnetic carbon nanotubes. The results were confirmed using UV-visible spectroscopy. In the four part, the feasibility of using MCNT as surface-assisted laser desorption/ionization (SALDI) matrix for the analysis of peptides and insulin was examined.