DNA-Conjugated Quantum Dot Nanoprobe for High-Sensitivity Fluorescent Detection of DNA and micro-RNA
DNA-Conjugated Quantum Dot Nanoprobe for High-Sensitivity Fluorescent Detection of DNA and micro-RNA
复制标题
DNA 共轭量子点纳米探针用于 DNA 和 micro-RNA 的高灵敏度荧光检测
DOI：
10.1021/am404811j
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发表时间：
2014-01-22
影响因子：
9.5
通讯作者：
Wang, Lianhui
中科院分区：
文献类型：
--
作者：
Su, Shao;Fan, Jinwei;Wang, Lianhui
在此，我们报告了一种开发用于DNA和微rna （miRNA）检测的基于量子点（QDs）的纳米传感器的便捷方法。采用配体交换法制备了dna -量子点共轭物。巯基标记的ssDNA直接附着在量子点表面，形成高度水分散的纳米偶联物。DNA-量子点共轭物具有量子点优良的光学特性和DNA识别特性可控的优点，可作为纳米探针构建核酸检测纳米传感器。加入目标核酸序列后，量子点的荧光强度通过Forster共振能量转移被有机猝灭剂BHQ(2)猝灭。这种纳米传感器可以检测低至1fm的DNA和10fm的miRNA。此外，基于qds的纳米传感器表现出优异的选择性。它不仅能有效区分单碱基错配和随机核酸序列，还能识别pre-miRNA和成熟miRNA。因此，纳米传感器在疾病诊断和生物学分析方面具有很大的应用潜力。
Herein, we report a convenient approach to developing quantum dots (QDs)-based nanosensors for DNA and micro-RNA (miRNA) detection. The DNA-QDs conjugate was prepared by a ligand-exchange method. Thiollabeled ssDNA is directly attached to the QD surface, leading to highly water-dispersible nanoconjugates. The DNA-QDs conjugate has the advantages of the excellent optical properties of QDs and well-Controlled recognition properties of DNA and can be used as a nanoprobe to construct a nanosensor for nucleic acid detection. With the addition of a target nucleic acid sequence, the fluorescence intensity of QDs was quenched by an organic quencher (BHQ(2)) via Forster resonance energy transfer. This nanosensor can detect as low as 1 fM DNA and 10 fM miRNA. Moreover, the QDs-based nanosensor exhibited excellent selectivity. It not only can effectively distinguish single-base-mismatched and random nucleic sequences but also can recognize pre-miRNA and mature miRNA. Therefore, the nanosensor has high application potential for disease diagnosis and biological analysis.