Key Laboratory of Analytical Chemistry for Life Science (Ministry of Education of China), Department of Chemistry, Nanjing University, Nanjing 210093, PR China.
Anal Chem. 2010 Jul 1;82(13):5511-7. doi: 10.1021/ac100852z.
This work designed a novel platform for effective sensing of biomolecules by fluorescence resonance energy transfer (FRET) from quantum dots (QDs) to graphene oxide (GO). The QDs were first modified with a molecular beacon (MB) as a probe to recognize the target analyte. The strong interaction between MB and GO led to the fluorescent quenching of QDs. Upon the recognition of the target, the distance between the QDs and GO increased, and the interaction between target-bound MB and GO became weaker, which significantly hindered the FRET and, thus, increased the fluorescence of QDs. The change in fluorescent intensity produced a novel method for detection of the target. The GO-quenching approach could be used for detection of DNA sequences, with advantages such as less labor for synthesis of the MB-based fluorescent probe, high quenching efficiency and sensitivity, and good specificity. By substituting the MB with aptamer, this strategy could be conveniently extended for detection of other biomolecules, which had been demonstrated by the interaction between aptamer and protein. To the best of our knowledge, this is the first application of the FRET between QDs and GO and opens new opportunities for sensitive detection of biorecognition events.
这项工作设计了一种新颖的平台，通过荧光共振能量转移（FRET）从量子点（QDs）到氧化石墨烯（GO）有效地感应生物分子。首先，将量子点用分子信标（MB）修饰作为探针来识别目标分析物。MB 与 GO 之间的强相互作用导致 QDs 的荧光猝灭。在识别目标后，QDs 和 GO 之间的距离增加，并且目标结合的 MB 与 GO 之间的相互作用变得更弱，这显著阻碍了 FRET，从而增加了 QDs 的荧光强度。荧光强度的变化产生了一种检测目标的新方法。GO 猝灭法可用于检测 DNA 序列，具有合成基于 MB 的荧光探针所需的劳动力较少、高猝灭效率和灵敏度以及良好的特异性等优点。通过用适体替代 MB，这种策略可以方便地扩展用于检测其他生物分子，这已经通过适体与蛋白质的相互作用得到了证明。据我们所知，这是首次将 QDs 和 GO 之间的 FRET 应用于生物识别事件的灵敏检测，并开辟了新的机会。
