Aptamer-Based Detection of Epithelial Tumor Marker Mucin 1 with Quantum Dot-Based Fluorescence Readout
Aptamer-Based Detection of Epithelial Tumor Marker Mucin 1 with Quantum Dot-Based Fluorescence Readout
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DOI：
10.1021/ac901223q
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发表时间：
2009-08-01
影响因子：
7.4
通讯作者：
Yu, Hua-Zhong
中科院分区：
文献类型：
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作者：
Cheng, Alan K. H.;Su, Huaipeng;Yu, Hua-Zhong
粘蛋白1（MUC 1）是一种表达于大多数上皮细胞表面的糖蛋白，已被证实是诊断早期癌症的有用生物标志物。在本文中，我们报告了一种基于适体的MUC 1定量检测方案，该方案使用量子点（QD）标记的三组分DNA杂交系统：在不存在MUC 1肽的情况下，在混合三条特别设计的DNA链时观察到强烈的荧光（猝灭剂、QD标记的报道分子和MUC 1适体茎）;在MUC 1肽存在下，检测到荧光强度的连续降低，因为MUC 1肽以这样的方式结合适体链，使得猝灭剂和荧光报告子紧密接近（这导致猝灭剂和QD之间发生荧光共振能量转移FRET）。用这种新方法对MUC 1的检测限为纳摩尔（nM）水平，并且可以在血清中发现的近似范围内建立线性响应。这项研究还提供了进一步了解MUC 1的适体/分析物结合位点/模式，这增加了改进这种检测方法用于大人群不同类型上皮癌早期诊断的可能性。
Mucin 1 (MUC1) is a glycoprotein expressed on most epithelial cell surfaces, which has been confirmed as a useful biomarker for the diagnosis of early cancers. In this paper,we report an aptamer-based, quantitative detection protocol for MUC1 using a 3-component DNA hybridization system with quantum dot (QD)-labeling: in the absence of MUC1 peptides, strong fluorescence is observed upon mixing the three specially designed DNA strands (quencher, QD-labeled reporter, and the MUC1 aptamer stem); in the presence of MUC1 peptides, a successive decrease in fluorescence intensity is detected since the MUC1 peptide binds to the aptamer strand in such a way to allow the quencher and fluorescence reporter to be brought into close proximity (which leads to the occurrence of fluorescence resonance energy transfer, FRET, between the quencher and QD). The detection limit for MUC1 with this novel approach is in the nanomolar (nM) level, and a linear response can be established for the approximate range found in blood serum. This study also provided further insight into the aptamer/analyte binding site/mode for MUC1, which augments the possibility of improving this detection methodology for the early diagnosis of different types of epithelial cancers of large populations.