Electrochemical regulation of nucleic acids hybridization

本论文尝试将修饰的脱氧核糖核酸（ssDNA）和三联吡啶单元（terpy 2DNA）分别固定在碳电极和金电极上。通过芘、芘等芳香族分子与HOPG的堆积作用，将ssDNA固定在HPOG电极上，并通过电化学方法检测其电化学性质的变化。利用巯基对Au的特异亲和性，将terpy 2 DNA固定在Au电极上.不幸的是，没有观察到ssDNA中巯基/二硫键氧化还原对的电化学信号。电位将超出测量窗口。terpy 2DNA与某些二价过渡金属离子形成分子内1：2络合物，形成[Fe（terpy）2]2+。在Au电极上观察到[Fe（terpy）2]2+/3+在terpy 2DNA上的氧化还原曲线。通过对SWV测量的频率依赖性来监测terpy 2DNA的杂交。

I have been trying to immobilize modified DNA carrying disulfide-bridged deoxyribose (ssDNA) and two terpyridine units (terpy2DNA) on carbon and gold electrode, respectively. I expect that I can monitor the hybridization by the change in their electrochemical properties.ssDNA was immobilized on HPOG electrode through stacking interaction of aromatic molecules such as pyrene and perylene onto the HOPG. terpy2DNA was immobilized on Au electrode by using specific affinity of sulfhydryl group, which was modified at the end of terpy2DNA, to Au. Unfortunately, the electrochemical signal of sulfhydryl/disulfide redox pair in ssDNA was not observed. The potential would be out of the measurement window. terpy2DNA formed intramolecular 1:2 complex with some divalent transition metal ions to form [Fe(terpy)2]2+. The redox profile of [Fe(terpy)2]2+/3+ on terpy2DNA was clearly observed on the Au electrode. The hybridization of terpy2DNA was monitored by frequency dependence on SWV measurement.