在高序热解石墨(HOPG)电极上,采用微分脉冲伏安法(DPV)和电化学原子力显微镜法(ECAFM)探究小牛胸腺DNA(CTDNA)在电极表面的吸附.实验发现,控制电位下预极化对双链DNA在HOPG电极上的吸附有很大的影响,而对单链DNA影响不大.实验表明,在HOPG电极上ECAFM是DNA研究领域十分有用的技术,根据AFM图象,结合文献上的DNA吸附模型提出了CTDNA在HOPG电极表面DNA吸附的模型.本文还首次采用现场紫外可见反射光谱研究DNA的电化学行为,发现对研究DNA的吸附该技术具有比伏安法更高的灵敏度
It is shown that calf thymus DNA(CT DNA) can be adsorbed at highly
ordered pyrolytic graphite(HOPG) electrode and detected by differential pulse voltammetry(DPV)
and electrochemical atomic force microscopy(ECAFM). It is found that controlled potential
pre-polarization influences largely the adsorption of dsDNA while it has little influence on
ssDNA. It is demonstrated that ECAFM is useful to exploit adsorption of DNA at HOPGE. The
pattern of adsorption of DNA at HOPG electrode that fits best with the experimental data is
proposed. The results aslo shows that UV/Vis reflection spectroscopy, which has not been used
in studying electrochemical behavior of DNA, is more sensitive than voltammetry in the
investigation of DNA adsorption.
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