Department of Chemistry, Liaocheng University, Liaocheng, Shandong 252059, PR China.
Department of Chemistry, Liaocheng University, Liaocheng, Shandong 252059, PR China.
Biosens Bioelectron. 2015 May 15;67:139-45. doi: 10.1016/j.bios.2014.07.073. Epub 2014 Aug 4.
8-Hydroxy-2'-deoxyguanosine (8-OH-dG) is the most abundant oxidative product of DNA and it is also considered to be a biomarker of oxidative DNA damage. In this work, a novel biosensor was fabricated by combining the biocompatibility of single-stranded DNA (ss-DNA) and the excellent conductivity of graphene nanosheets (GNs). The biosensor showed high electrocatalytic activity to the oxidation of 8-OH-dG. The sensitivities were 13.23 (±0.03)μA μM(-1), 5.827 (±0.008) μA μM(-1) and 3.086 (±0.005) μA μM(-1) in the concentration ranges of 0.0056-1.155 μM, 1.155-11.655 μM and 11.655-36.155 μM, respectively. The detection limit was 0.875 nM (S/N=3). Furthermore, the electrochemical behavior of 8-OH-dG was also investigated in detail in the presence of uric acid. And the results showed that uric acid had interference with the trace detection of 8-OH-dG. But it can be eliminated completely by uricase. The as-prepared ss-DNA/GNs/GCE will be promising for the detection of 8-OH-dG in real samples.
8-羟基-2'-脱氧鸟苷（8-OH-dG）是 DNA 中最丰富的氧化产物，也被认为是氧化 DNA 损伤的生物标志物。在这项工作中，通过将单链 DNA（ss-DNA）的生物相容性和石墨烯纳米片（GNs）的优异导电性结合起来，构建了一种新型的生物传感器。该生物传感器对 8-OH-dG 的氧化具有高电催化活性。在 0.0056-1.155 μM、1.155-11.655 μM 和 11.655-36.155 μM 的浓度范围内，其灵敏度分别为 13.23（±0.03）μA μM(-1)、5.827（±0.008）μA μM(-1)和 3.086（±0.005）μA μM(-1)。检测限为 0.875 nM（S/N=3）。此外，还详细研究了尿酸存在下 8-OH-dG 的电化学行为。结果表明，尿酸对痕量检测 8-OH-dG 有干扰，但尿酸酶可以完全消除这种干扰。所制备的 ss-DNA/GNs/GCE 将有望用于实际样品中 8-OH-dG 的检测。
