标题: | 金奈米电极核酸感测器之制造与电性量测研究 Fabrication and Electrical Detection of DNA Sensor with Gold Nanoelectrodes |
作者: | 陈界佐 Chieh-Tso Chen 刘增丰 柯富祥 Tzeng-Feng Liu Fu-Hsiang Ko 材料科学与工程学系奈米科技硕博士班 |
关键字: | 核酸感测器;DNA sensor |
公开日期: | 2004 |
摘要: | 近几年来,有许多以电性侦测为基础的核酸分析技术已经被开发出来并且应用于基因疾病的诊断。在那些电性侦测技术中,其侦测方法最主要特色为避免使用聚合酶连锁反应(PCR)来放大核酸(DNA)分子的浓度与避免使用昂贵的光学设备以撷取萤光DNA的放射讯号。 本论文主要在于研究以醛类衍生的核酸分子(aldehyde-derivatIzed DNA) 来达到电性侦测。在本实验中,我们结合电子微影技术及lift-off 技术在矽晶圆表面上制造出次奈米间隙的金奈米电极,在两电极中所暴露出的二氧化矽层先修饰上氨基分子接着在固定上27-mer 的单股核酸分子(capture DNA),然后加入已醛基官能化的核酸分子(target DNA)进行专一性的辨识。经由PBS缓冲溶液及去离子水的冲洗,核酸晶片以具有氧化性的多伦试剂(Tollen's reagent)处理;当target DNA 的序列与 capture DNA 互补时,银离子将会被限定在target DNA的醛基所还原出来并且延着DNA分子的骨架沈积,因此互补的双股核酸分子被多伦试剂金属化,而且金奈米电极所增加的电流可以直接被分析器量测出来。 In recent years, a variety of DNA assay techniques based on electrical detection for diagnosis of genetic and pathogenic diseases had been explored. Among those skills, the major characterizations of detection methods were to avoid the use of polymerase chain reaction for amplifying the concentration of analytic DNA and expensive optical microscope equipments to obtain emitting signals from fluorescent DNA. Herein, I investigated a novel strategy for the electrical detection of DNA by aldehyde-derivatized oligonucleotide probes. In this experimental protocol, we combined the shaped electron beam lithography to fabricate sub-nanometer gap between two electrode pads on silicon wafers, and the gold electrodes were fabricated by lift-off process. 27-mer single-stranded nucleic acids called as capture DNA were immobilized on exposed SiO2 surface modified with amino groups between two electrodes. Then analytical DNA (namely targets DNA) functionalized with aldehyde groups were spotted for occurring specific recognition. After washing with PBS buffer and DI water strictly, the DNA chip was handled with Tollen's reagent acted as oxidation agent. When the sequences of the target DNA were complementary to the capture strand, silver ions would be reduced by the aldehyde groups localized on base within DNA and deposited along with the DNA skeleton. Hence, the complementary double-stranded DNA molecules were metallized by Tollen's reagent and the increased currents across gold nanoelectrodes could be measured by analyzer directly. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT009252503 http://hdl.handle.net/11536/77501 |
显示于类别: | Thesis |