Highly Sensitive Photoelectrochemical Biosensor Based on Quantum Dots Sensitizing Bi2Te3 Nanosheets and DNA-Amplifying Strategies
Highly Sensitive Photoelectrochemical Biosensor Based on Quantum Dots Sensitizing Bi2Te3 Nanosheets and DNA-Amplifying Strategies
复制标题
DOI：
10.1021/acsami.0c04536
复制
发表时间：
2020-05-20
影响因子：
9.5
通讯作者：
Yuan, Ruo
中科院分区：
文献类型：
--
作者：
Yuan, Yali;Hu, Tao;Yuan, Ruo
在这项工作中，用n -乙烯基吡咯烷酮处理的Bi2Te3纳米片具有高度充足和稳定的光电流，可以作为一种新型的光活性材料。因此，利用CdTe量子点（QDs）敏化Bi2Te3纳米片，构建了耦合dna扩增策略的光电化学（PEC）生物传感器，用于灵敏的miRNA-21检测。最初，电极上的Bi2Te3纳米片具有具有无耗散电子特性的导电表面态，从而提供高度稳定的光电流和大的表面体积比。然后，在目标miRNA-21和辅助DNA的参与下，发生链位移扩增，从而打开大量的DNA发夹，触发下一个杂交链反应（HCR）。通过HCR，可以在电极上组装带有CdTe量子点修饰的DNA长尾，从而增强Bi2Te3纳米片的光电流。实验结果表明，PEC生物传感器的检测范围从10 fM到100 pM，检测限为3.3 fM，为构建简单、超灵敏、稳定的分析技术提供了良好的途径，在生物分析和早期临床诊断方面具有巨大的潜力。
In this work, Bi2Te3 nanosheets treated with N-vinyl-pyrrolidinone showed highly sufficient and stable photo-current for being used as a novel photoactive material. Accordingly, with CdTe quantum dots (QDs) sensitizing Bi2Te3 nanosheets, photoelectrochemical (PEC) biosensor coupling of DNA-amplifying strategies was constructed for sensitive miRNA-21 detection. Initially, the Bi2Te3 nanosheets on the electrode have conductive surface states with dissipationless electronic property, thus providing a highly stable photocurrent and a large surface-to-volume ratio. Then, with the participation of target miRNA-21 and auxiliary DNA, strand displacement amplification took place, thereby opening substantial DNA hairpins for triggering the next hybridization chain reaction (HCR). Through the HCR, long DNA tails decorated with CdTe QDs could thus be assembled on the electrode for enhancing the photocurrent of Bi2Te3 nanosheets. As a result, the proposed PEC biosensor showed a wide detection range from 10 fM to 100 pM with a detection limit of 3.3 fM, displaying a promising avenue to construct simple, ultrasensitive, and stable analytical techniques and tremendous potential in bioanalysis and early clinical diagnosis.