Institute of Ocean Research, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.
Department of Food Science and Technology, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.
Mikrochim Acta. 2019 Apr 26;186(5):303. doi: 10.1007/s00604-019-3392-y.
A method is described for the fluorometric determination of DNA containing oxidatively damaged product 8-hydroxy-2'-deoxyguanosine (DNA-8-OHdG). Carbon dots (CDs) were modified with glutaraldehyde for DNA conjugation, and antibody against 8-OHdG was immobilized on gold nanoparticles (AuNPs). The presence of DNA-8-OHdG can be linked to CDs by reaction of amino groups on DNA with glutaraldehyde. AuNPs were brought closely to CDs by specific immune reaction between 8-OHdG and antibody on AuNPs. Under 350 nm photoexcitation, the emission of CDs with a peak at 440 nm is quenched by the AuNPs and not restored. In the presence of DNA-8-OHdG, the measured fluorescence intensity decreases and quenching efficiency increases. The limit of detection is 700 pM, and the assay works in the 0.01 nM to 25 μM DNA-8-OHdG concentration range. The method is perceived to possess a good potential as a tool for detecting biomarkers for DNA damage due to oxidative stress. Graphical abstract A fluorometric immunoassay for detecting 8-hydroxy-2'-deoxyguanosine (8-OHdG) in oxidatively damaged DNA is reported. It is based on the use of carbon dots (CDs) and gold nanoparticles (AuNPs). Black wavy lines represent DNA. Yellow polygonal sharps represent 8-OHdG. Blue and pink balls represent CDs and AuNPs, respectively.
一种用于荧光测定含氧化损伤产物 8-羟基-2'-脱氧鸟苷（DNA-8-OHdG）的 DNA 的方法。碳点（CDs）用戊二醛修饰以用于 DNA 缀合，并且针对 8-OHdG 的抗体被固定在金纳米粒子（AuNPs）上。DNA-8-OHdG 的存在可以通过 DNA 上的氨基与戊二醛的反应与 CDs 相连。通过 AuNPs 上的 8-OHdG 和抗体之间的特异性免疫反应，AuNPs 被紧密地带到 CDs 附近。在 350nm 光激发下，具有 440nm 峰的 CDs 的发射被 AuNPs 猝灭并且不会恢复。在存在 DNA-8-OHdG 的情况下，测量的荧光强度降低并且猝灭效率增加。检测限为 700pM，并且该测定在 0.01nM 至 25μM DNA-8-OHdG 浓度范围内起作用。该方法被认为具有作为检测由于氧化应激引起的 DNA 损伤的生物标志物的工具的良好潜力。
