Direct measurement of the melting temperature of supported DNA by electrochemical method
Direct measurement of the melting temperature of supported DNA by electrochemical method
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DOI：
10.1093/nar/gng150
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发表时间：
2003-12-01
影响因子：
14.9
通讯作者：
Latruffe, N
中科院分区：
文献类型：
--
作者：
Meunier-Prest, R;Raveau, S;Latruffe, N
基于DNA杂交的生物传感器的发展需要更精确的知识在固体界面上的杂交的热力学。特别地，杂交的选择性可受许多参数如单链（ss）DNA密度、pH、离子强度或温度的影响。解链温度T-m部分是离子强度和温度的函数，因此在控制DNA芯片的选择性和灵敏度中提供了有用的变量。用电化学方法测定了探针与DNA自组装膜（SAM）连接时的Tm值。我们已经建立了一个特殊的薄层细胞，它允许在受控温度条件下记录的循环伏安图。通过记录双链杂交（dsDNA）修饰电极上的氧化还原指示剂的热谱图（电流与温度）并与相应的ssDNA响应进行比较来确定Tm。负载DNA的Tm随离子强度的变化呈线性关系。考虑了自组装膜的稳定性，并对溶液中的T-m和固体载体上的T-m进行了比较。
The development of biosensors based on DNA hybridization requires a more precise knowledge of the thermodynamics of the hybridization at a solid interface. In particular, the selectivity of hybridization can be affected by a lot of parameters such as the single-strand (ss)DNA density, the pH, the ionic strength or the temperature. The melting temperature, T-m, is in part a function of the ionic strength and of the temperature and therefore provides a useful variable in the control of the selectivity and sensitivity of a DNA chip. The electrochemical technique has been used to determine the T-m values when the probe is tethered by a DNA self-assembled monolayer (SAM). We have built a special thin layer cell, which allows the recording of the cyclic voltammogram under controlled temperature conditions. T-m has been determined by recording the thermogram (current versus temperature) of a redox indicator on a double-stranded hybrid (dsDNA) modified electrode and comparison with the corresponding ssDNA response. T-m of supported DNA varies linearly with the ionic strength. The stability of the SAMs has been considered and comparison between T-m in solution and on a solid support has been discussed.