Li Fenglan, Cai Qianqian, Hao Xiaoli, Zhao Chengfei, Huang Zhengjun, Zheng Yanjie, Lin Xinhua, Weng Shaohuang
Department of Pharmaceutical Analysis, School of Pharmacy, Fujian Medical University Fuzhou 350122 China
Nano Biomedical Technology Research Center, Fujian Medical University Fuzhou 350122 China.
RSC Adv. 2019 Apr 23;9(22):12462-12469. doi: 10.1039/c9ra00881k. eCollection 2019 Apr 17.
Considerable biosensors have been fabricated on the basis of DNA interaction with carbon nanomaterials, such as graphene oxide (GO) nanosheets. Few studies have focused on the rational design of sensors between carbon dots (CDs) and DNA due to the limited understanding of the real forces behind the adsorption of DNA on CDs. In this work, nitrogen doping-positive CDs (N-CDs), which can quench fluorophore-labeled DNA, were investigated to ascertain the interaction between the CDs and DNA. With reference to DNA adsorption on GO, the adsorption capacity and kinetics of N-CDs for DNA were studied. Desorption of DNA from these surfaces was also measured. Moreover, DNA desorption and anchoring force of N-CDs to DNA were different from those of GO, given that the prepared N-CDs and GO were positively and negatively charged, respectively. Accordingly, DNA was adsorbed on N-CDs mainly electrostatic adsorption and other forces, such as nucleobase effect, hydrophobic interaction, and van der Waals (vdW) forces. This study enhanced the basic knowledge of DNA adsorption on some CDs for further study in the application of CDs in bioanalysis or biomedicine.
基于DNA与碳纳米材料（如氧化石墨烯（GO）纳米片）的相互作用，已经制备了大量的生物传感器。由于对DNA吸附在碳点（CDs）上背后的实际作用力了解有限，很少有研究关注CDs与DNA之间传感器的合理设计。在这项工作中，研究了能够淬灭荧光团标记DNA的氮掺杂正电荷CDs（N-CDs），以确定CDs与DNA之间的相互作用。参照DNA在GO上的吸附情况，研究了N-CDs对DNA的吸附容量和动力学。还测量了DNA从这些表面的解吸情况。此外，鉴于制备的N-CDs和GO分别带正电荷和负电荷，N-CDs对DNA的解吸和锚定力与GO不同。因此，DNA主要通过静电吸附以及其他作用力（如核碱基效应、疏水相互作用和范德华（vdW）力）吸附在N-CDs上。这项研究增强了关于DNA在某些CDs上吸附的基础知识，以便在CDs用于生物分析或生物医学的应用中进行进一步研究。
