Environment Division, Korea Institute of Science and Technology, 39-1 Hawolgok-dong, Seongbuk-gu, Seoul, 136-791, South Korea.
Analyst. 2011 Sep 21;136(18):3720-4. doi: 10.1039/c1an15261k. Epub 2011 Jul 28.
We developed a homogeneous fluorescence assay for multiplex detection based on the target induced conformational change of DNA aptamers. DNA aptamers were immobilized on quantum dots (QDs), and QDs conjugated ssDNA was adsorbed on the surface of gold nanoparticles (AuNPs) by electrostatic interaction between uncoiled ssDNA and the AuNPs. Subsequently the fluorescence of QDs was effectively quenched by the AuNPs due to fluorescence resonance energy transfer (FRET) of QDs to AuNPs. In the presence of targets, the QDs conjugated aptamers were detached from AuNPs by target induced conformational change of aptamers, consequently the fluorescence of the QDs was recovered proportional to the target concentration. In this study, three different QD/aptamer conjugates were used for multiplex detection of mercury ions, adenosine and potassium ions. In a control experiment, all of the three targets were simultaneously detected with high selectivity.
我们开发了一种基于 DNA 适体靶标诱导构象变化的多重荧光检测均相分析方法。DNA 适体被固定在量子点（QDs）上，而通过未卷曲的单链 DNA 与金纳米颗粒（AuNPs）之间的静电相互作用，将与 QDs 偶联的单链 DNA 吸附在 AuNPs 的表面上。随后，由于 QDs 到 AuNPs 的荧光共振能量转移（FRET），AuNPs 有效地猝灭了 QDs 的荧光。在存在靶标的情况下，通过适体的靶标诱导构象变化，与 AuNPs 偶联的 QDs 适体被从 AuNPs 上脱离，因此 QDs 的荧光与靶标浓度呈比例恢复。在这项研究中，三种不同的 QD/适体偶联物被用于同时检测汞离子、腺苷和钾离子。在对照实验中，三种靶标都被同时高选择性地检测到。
