An electrochemical dsDNA nanobiosensor was fabricated using amino‐functionalized multi walled carbon nanotubes modified glassy carbon electrode (NH₂fMWCNTs/GCE) for the sensitive detection of DNA bases and electrochemical monitoring of drug‐DNA interaction. The influence of functional groups on MWCNT was studied by MWCNT functionalized with NH₂ (NH₂fMWCNTs) and COOH (COOHfMWCNT) groups based on the signal of DNA bases. The modified electrodes were characterized by scanning electron microscopy. One layer of calf thymus double stranded deoxyribonucleic acid (ct‐dsDNA) was immobilized onto the NH₂fMWCNTs/GCE (dsDNA/NH₂fMWCNTs/GCE). The dsDNA/NH₂fMWCNTs/GCE were used to investigate the interaction between the dsDNA and the anticancer drug gemcitabine by differential pulse voltammetry in acetate buffer of pH 4.70. For the confirmation of interaction, the lowering in intensity of the current signals of guanine and adenine was considered as an indicator. Electrochemical impedance spectroscopy studies were performed for the comparison of the modified surfaces. In order to define and visualize the interaction mechanism between gemcitabine and dsDNA/NH₂fMWCNTs/GCE at the molecular level, in silico methods including docking and molecular dynamics simulations were employed.

中文翻译：

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NH2-MWCNTs修饰玻碳电极上的灵敏核酸检测及其在吉西他滨-DNA相互作用监测中的应用

使用氨基官能化的多壁碳纳米管修饰的玻碳电极（NH ₂ f MWCNTs / GCE）制备了电化学dsDNA纳米生物传感器，用于DNA碱基的灵敏检测和药物-DNA相互作用的电化学监测。基于DNA碱基的信号，通过NH ₂（NH ₂ f MWCNTs）和COOH（COOH f MWCNT）基团分别官能化的MWCNT，研究了官能团对MWCNT的影响。修饰的电极通过扫描电子显微镜表征。将一层小牛胸腺双链脱氧核糖核酸（ct-dsDNA）固定在NH ₂ f MWCNTs / GCE（dsDNA / NH ₂ fMWCNTs / GCE）。dsDNA / NH ₂ f MWCNTs / GCE通过差示脉冲伏安法在pH 4.70的乙酸缓冲液中研究dsDNA与抗癌药物吉西他滨之间的相互作用。为了确认相互作用，认为鸟嘌呤和腺嘌呤的电流信号的强度降低是指示剂。进行了电化学阻抗谱研究，以比较改性表面。为了在分子水平上定义和可视化吉西他滨与dsDNA / NH ₂ f MWCNTs / GCE之间的相互作用机理，采用了计算机模拟方法，包括对接和分子动力学模拟。