Hu Chenyan, Yang Zhongzhu, Song Zhen, Xiao Linghui, He Yang
College of Medical Technology, State Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China, Chengdu University of Traditional Chinese Medicine Chengdu 611137 China
Hospital of Chengdu University of Traditional Chinese Medicine Chengdu 610075 China
RSC Adv. 2020 Apr 16;10(25):14944-14952. doi: 10.1039/d0ra00142b. eCollection 2020 Apr 8.
In recent years, graphene oxide quantum dots (GOQDs) have emerged as novel nanomaterials for optical sensing, bioimaging, clinical testing, and environmental testing. However, GOQDs demonstrate unique photoluminescence properties, with GOQDs having quantum limitations and edge effects that often affect the accuracy of the test results in the sensory field. Herein, GOQDs with a large content of hydroxyl groups and low fluorescence intensity were first prepared an improved Fenton reaction in this study, which introduces a large amount of epoxy groups to break the C-C bonds. The synthesized GOQDs show no significant variation in the fluorescence intensity upon ultraviolet and visible light excitations. We further utilized the GOQDs as fluorescence quenchers for different fluorescent dyes in real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), and verified that the addition of GOQDs (5.3 μg ml) into a qRT-PCR system could reduce the background fluorescence intensity of the reaction by fluorescence resonance energy transfer (FRET) during its initial stage and its non-specific amplification, and improve its specificity. In addition, the qRT-PCR method could detect two different lengths of DNA sequences with a high specificity in the 10 to 10 copies per μl range. It is of paramount importance to carry out further investigations to establish an efficient, sensitive, and specific RT-PCR method based on the use of GOQD nanomaterials as fluorescence quenchers.
近年来，氧化石墨烯量子点（GOQDs）已成为用于光学传感、生物成像、临床检测和环境检测的新型纳米材料。然而，GOQDs表现出独特的光致发光特性，其具有量子限制和边缘效应，这常常影响传感领域测试结果的准确性。在本研究中，首先通过改进的芬顿反应制备了具有大量羟基和低荧光强度的GOQDs，该反应引入大量环氧基团以断裂碳 - 碳键。合成的GOQDs在紫外光和可见光激发下荧光强度无显著变化。我们进一步将GOQDs用作实时荧光定量聚合酶链反应（qRT-PCR）中不同荧光染料的荧光猝灭剂，并证实向qRT-PCR系统中加入5.3 μg/ml的GOQDs可在反应初始阶段及其非特异性扩增过程中通过荧光共振能量转移（FRET）降低反应的背景荧光强度，并提高其特异性。此外，qRT-PCR方法能够在每微升10至10个拷贝的范围内高特异性地检测两种不同长度的DNA序列。基于使用GOQD纳米材料作为荧光猝灭剂开展进一步研究以建立高效、灵敏且特异的RT-PCR方法至关重要。
