Supersandwich Cytosensor for Selective and Ultrasensitive Detection of Cancer Cells Using Aptamer-DNA Concatamer-Quantum Dots Probes
Supersandwich Cytosensor for Selective and Ultrasensitive Detection of Cancer Cells Using Aptamer-DNA Concatamer-Quantum Dots Probes
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使用适体-DNA 串联体-量子点探针选择性超灵敏检测癌细胞的超级三明治细胞传感器
DOI：
10.1021/ac303789x
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发表时间：
2013-03-19
影响因子：
7.4
通讯作者：
Zhu, Jun-Jie
中科院分区：
文献类型：
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作者：
Liu, Hongying;Xu, Shouming;Zhu, Jun-Jie
在这项工作中，发展了一种信号放大超夹层策略，用于使用适体-DNA串联量子点(QDS)探针对癌细胞进行高选择性和高灵敏度的检测。首先，利用多壁碳纳米管(MWCNTs)、金纳米颗粒(AuNPs)和多聚多巴胺(PDA)采用逐层法制备了MVVCNTs@PDA@AuNPs电极材料。然后，将所制备的碱基作为基质与刀豆蛋白A(ConA)结合，获得了高稳定性、生物活性和细胞捕获能力。同时，通过DNA杂交和共价组装设计了适体-DNA连接体-量子点，它将适体的特异性识别与DNA连接体和量子点的信号放大结合在一起。以适体-DNA链接物-量子点为识别探针，用捕获ConA的MWCNTs@PDA@AuNPs修饰电极对模型癌细胞(CCRF-CEM细胞)进行了荧光检测和电化学检测。该超夹心细胞传感器具有很高的灵敏度，检测下限为50细胞毫升(-1)。更重要的是，它可以区分癌细胞和正常细胞，这表明我们的方法在癌症的临床诊断和治疗中具有很好的应用前景。
In this work, a signal amplification supersandwich strategy was developed for highly selective and sensitive detection of cancer cells using aptamer-DNA concatamerquantum dots (QDs) probes. First of all, electrode materials denoted as MVVCNTs@PDA@AuNPs were fabricated by multiwall carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs), and polydopamine (PDA) using a layer-by-layer technique. Then, the prepared bases as matrices were applied to bind concanavalin A (Con A), resulting in high stability, bioactivity, and capability for cell capture. Meanwhile, aptamer-DNA concatamer-QDs were designed via DNA hybridization followed by covalent assembling, which incorporated the specific recognition of the aptamer with the signal amplification of the DNA concatamer and QDs. With aptamer-DNA concatamer-QDs as recognizing probes, the model cancer cells (CCRF-CEM cells) were detected using a MWCNTs@PDA@AuNPs modified electrode with trapped Con A by means of fluorescence and electrochemical methods. The proposed supersandwich cytosensor showed high sensitivity with the detection limit of 50 cells mL(-1). More importantly, it could distinguish cancer cells from normal cells, which indicated the promising applications of our method in clinical diagnosis and treatment of cancers.