Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Guilan, Namjoo Street, P.O. Box: 1914-41335, Rasht, Iran.
Electroanalytical Chemistry Laboratory, Faculty of Chemistry, University of Guilan, Namjoo Street, P.O. Box: 1914-41335, Rasht, Iran.
Anal Chim Acta. 2017 Sep 15;986:25-41. doi: 10.1016/j.aca.2017.07.057. Epub 2017 Jul 29.
A new nanocomposite film constructed of poly-l-cysteine/zinc oxide nanoparticles-electrospun copper oxide nanofibers (PLC/ZnO-NPs-CuO-NFs) was prepared on the surface of the graphite electrode (GE). The novel electrode was successfully applied for the simultaneous determination of guanine (G) and adenine (A), two of the most important components of DNA and RNA. The PLC/ZnO-NPs-CuO-NFs/GE enhanced the anodic peak currents of the purine bases conspicuously and could determine them sensitively and separately in 0.1 M phosphate buffer solution at the physiological pH (7.0). The synthesized nanofibers, nanoparticles and nanocomposite were characterized by different methods such as Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDS). Under the optimum operating conditions, linear calibration curves were obtained in the range of 0.05-6.78 and 0.01-3.87 μM with a detection limit of 12.48 and 1.25 nM for G and A, respectively. The proposed method was applied to quantify A and G in three different DNA samples with satisfactory results. In addition, damage to human blood double-stranded DNA (dsDNA) and DNA purine bases (liberated in previously hydrolyzed human blood dsDNA) caused by UV-C and UV-B were evaluated. The results demonstrated that the proposed biosensing platform not only provides a novel and sensitive approach to detecting DNA damage, but also can be used for simultaneous determination of purine bases and major products of DNA oxidative damage.
一种新型的纳米复合膜，由聚-l-半胱氨酸/氧化锌纳米粒子-电纺氧化铜纳米纤维（PLC/ZnO-NPs-CuO-NFs）构建，被制备在石墨电极（GE）的表面。这种新型电极成功地应用于同时测定鸟嘌呤（G）和腺嘌呤（A），这是 DNA 和 RNA 的两个最重要的组成部分。PLC/ZnO-NPs-CuO-NFs/GE 显著增强了嘌呤碱基的阳极峰电流，可以在生理 pH 值（7.0）的 0.1 M 磷酸盐缓冲溶液中灵敏且分别地测定它们。合成的纳米纤维、纳米粒子和纳米复合材料通过傅里叶变换红外光谱（FT-IR）、透射电子显微镜（TEM）、扫描电子显微镜（SEM）、场发射扫描电子显微镜（FE-SEM）、原子力显微镜（AFM）、X 射线衍射（XRD）和能量色散 X 射线分析（EDS）等不同方法进行了表征。在最佳工作条件下，对于 G 和 A，在 0.05-6.78 和 0.01-3.87 μM 的范围内获得了线性校准曲线，检测限分别为 12.48 和 1.25 nM。该方法被应用于三种不同 DNA 样品中 A 和 G 的定量，结果令人满意。此外，还评估了 UV-C 和 UV-B 对人血双链 DNA（dsDNA）和 DNA 嘌呤碱基（先前水解的人血 dsDNA 中释放的）的损伤。结果表明，该生物传感平台不仅提供了一种新颖而灵敏的检测 DNA 损伤的方法，而且还可以用于同时测定嘌呤碱基和 DNA 氧化损伤的主要产物。
