Key Laboratory of Industrial Ecology and Environment Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Key Laboratory of Industrial Ecology and Environment Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Biosens Bioelectron. 2015 Jun 15;68:7-13. doi: 10.1016/j.bios.2014.12.048. Epub 2014 Dec 23.
A sensitive, rapid and label-free assay for colorimetric detection of human 8-hydroxyguanine glycosylase (hOGG1) was proposed based on the tunable catalytic ability of graphene/gold nanoparticles (graphene/Au-NPs) hybrids and the terminal protection of hOGG1. In presence of H2O2, the hybrids were capable of catalyzing the oxidation of color developing reagent, causing a concomitant change in color. Due to the excellent controllability, the capacity could be inhibited by adsorption of ssDNA onto the hybrids sheets and recovered when the adsorbed ssDNA was digested by exonuclease. The terminal protection of hOGG1 could irreversibly interrupt the digestion of the captured ssDNA (containing the oxidative damage site) by the exonuclease, thus preventing the catalytic ability of graphene/Au-NPs from being recovered. The original color change which related to the concentration of the protected ssDNA facilitated quantitative detection of hOGGl activity. Compared with conventional methods for hOGG1 detection, the presented assay without any labeling process greatly simplified the operation steps and reduced the analysis time. This approach performed a linear response for hOGG1 activity from 0.02 to 0.11 U/μL with a detection limit of 0.0016 U/μL, and realized the quantification of hOGG1 activity in real cell lines.
基于石墨烯/金纳米粒子（graphene/Au-NPs）杂化物的可调催化能力和人 8-羟基鸟嘌呤糖苷酶（hOGG1）的末端保护，提出了一种用于比色检测 hOGG1 的灵敏、快速和无标记的分析方法。在 H2O2 的存在下，杂化物能够催化显色试剂的氧化，导致颜色发生伴随变化。由于具有优异的可控性，ssDNA 可以吸附到杂化物片上从而抑制其催化能力，而当吸附的 ssDNA 被核酸外切酶消化时，这种能力又可以恢复。hOGG1 的末端保护可以通过外切酶不可逆地中断捕获的 ssDNA（含有氧化损伤位点）的消化，从而防止 graphene/Au-NPs 的催化能力恢复。与传统的 hOGG1 检测方法相比，该方法无需任何标记过程，大大简化了操作步骤，缩短了分析时间。该方法对 hOGG1 活性的线性响应范围为 0.02-0.11 U/μL，检测限为 0.0016 U/μL，并实现了真实细胞系中 hOGG1 活性的定量检测。
