In this present study, single-walled carbon nanotubes (SWCNT) modified disposable pencil graphite electrodes (SWCNT-PGEs) were developed for the electrochemical monitoring of anticancer drug, and its interaction with double stranded DNA (dsDNA). Under this aim, SWCNT-PGEs were applied for the first time in the literature to analyse of 6-Thioguanine (6-TG), and also to investigate its interaction with DNA by voltammetric and impedimetric methods. The surface morphologies of PGE and SWCNT-PGE were explored using scanning electron microscopy (SEM) and electrochemical characterization of unmodified/modified electrodes was performed by cyclic voltammetry (CV). Experimental parameters; such as, the concentration of 6-TG and its interaction time with dsDNA were optimized by using differential pulse voltammetry (DPV). Additionally, the interaction of 6-TG with dsDNA was studied in case of different interaction times by electrochemical impedance spectroscopy (EIS) in contrast to voltammetric results. The detection limit of 6-TG was found to be 0.25 μM by SWCNT-PGE.

中文翻译：

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用于监测 6-硫鸟嘌呤和 DNA 之间生物相互作用的碳纳米管改性石墨电极

在本研究中，开发了单壁碳纳米管 (SWCNT) 修饰的一次性铅笔石墨电极 (SWCNT-PGE)，用于电化学监测抗癌药物及其与双链 DNA (dsDNA) 的相互作用。为此，文献中首次应用 SWCNT-PGEs 分析 6-硫鸟嘌呤 (6-TG)，并通过伏安法和阻抗法研究其与 DNA 的相互作用。使用扫描电子显微镜 (SEM) 探索 PGE 和 SWCNT-PGE 的表面形貌，并通过循环伏安法 (CV) 进行未改性/改性电极的电化学表征。实验参数；例如，通过使用差分脉冲伏安法 (DPV) 优化了 6-TG 的浓度及其与 dsDNA 的相互作用时间。此外，与伏安法结果相反，通过电化学阻抗谱 (EIS) 在不同相互作用时间的情况下研究了 6-TG 与 dsDNA 的相互作用。SWCNT-PGE 发现 6-TG 的检测限为 0.25 μM。