Study of the Immobilization and Detection of Oligonucleotides on Gold

• Main Authors: Zih-Ning Wang, 王子寧
• Other Authors: Tsung-Mei Chin
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/48865905867566438355

碩士 === 中國文化大學 === 應用化學研究所 === 95 === The use of miniaturized solid-phase surfaces for the biomolecule detection and analysis has become increasingly more attractive. The aim of this thesis is to develop a strategy of an immobilized oligonucleotide probe as a platform. The architecture of immobilized molecular layer is an important research area in the field of biosensing. The challenge connecting probes on the solid surface is to reduce as many as possible the side reactions during the procedures of chemical immobilization. Our approach is to anchor on the solid surface a simple and stable oligonucleotide which provides a platform for the attachment and molecular recognition of versatile probes. In this study, we selected the highly sensitive equipment, quartz crystal microbalance (QCM), to detect the immobilization of oligonucleotides and the target-probe hybridization. We have developed a simple, convenient and reliable procedure to anchor oligonucleotide probes on a gold-coated quartz crystal through formation of the S-Au bond, and then a complementary DNA fragment carrying a functional group successfully hybridized with the immobilized probe, and performed the desired bioanalysis. Two cleaning methods, SPM (sulfate peroxide mixture) and APM (ammonium peroxide mixture), was compared. The SPM method gave a better result in term of the reproducibility. According to the experimental results, only a little amount of the protein Av-Ap (lower than 2.5x10-8 g/mL) was needed to detect the biotin connected to an oligonucleotide probe. In addition, the QCM technology was more sensitive than the colormetric reaction.