Department of Chemistry, Shahid Bahonar University of Kerman, Kerman, Iran; Young Research Society, Shahid Bahonar University of Kerman, Kerman, Iran.
Department of Chemistry, Shahid Bahonar University of Kerman, Kerman, Iran.
Bioelectrochemistry. 2018 Dec;124:165-171. doi: 10.1016/j.bioelechem.2018.07.014. Epub 2018 Jul 19.
In this work an electrochemical label free DNA biosensor (ds-DNA) for the determination of menadione (MD) was developed. The biosensor was constructed using a modified nanocomposite consisting of FeO nanoparticles decorated reduced graphene oxide (Gr) on a carbon paste electrode (CPE). Scanning electron microscope (SEM), energy dispersive X-ray (EDAX) and Fourier transform infrared (FT-IR) spectroscopy confirmed the structure of the synthesized nanocomposites (electrode composition). The Gr-FeO nanocomposites formed a sensitive layer with large surface area. Electrochemical studies revealed that modification of the electrode surface with ds-DNA and Gr- FeO nanocomposite significantly increases the oxidation peak currents and reduces the peak potentials of MD. Under the optimum conditions, calibration curve was linear in the range of 0.3-100.0 nM with a detection limit of 0.13 nM. The relative standard deviation for 50.0 nM was 3.90% (n = 5). The proposed biosensor was successfully applied to the determination of MD.
本工作开发了一种用于测定亚甲二氢叶酸（MD）的电化学无标记 DNA 生物传感器（ds-DNA）。该生物传感器是使用包含 FeO 纳米粒子修饰的还原氧化石墨烯（Gr）的纳米复合材料构建的，该纳米复合材料修饰在碳糊电极（CPE）上。扫描电子显微镜（SEM）、能谱（EDAX）和傅里叶变换红外（FT-IR）光谱证实了合成纳米复合材料（电极组成）的结构。Gr-FeO 纳米复合材料形成了具有大表面积的敏感层。电化学研究表明，ds-DNA 和 Gr-FeO 纳米复合材料修饰电极表面可显著增加 MD 的氧化峰电流并降低峰电位。在最佳条件下，校准曲线在 0.3-100.0 nM 范围内呈线性关系，检测限为 0.13 nM。50.0 nM 时的相对标准偏差为 3.90%（n=5）。该生物传感器成功应用于 MD 的测定。
