Ultra-sensitive label-free electrochemical detection of the acute leukaemia tor gene Pax-5a based on enzyme-assisted cycle amplification
Ultra-sensitive label-free electrochemical detection of the acute leukaemia tor gene Pax-5a based on enzyme-assisted cycle amplification
复制标题
基于酶辅助循环扩增的急性白血病tor基因Pax-5a超灵敏无标记电化学检测
DOI：
10.1016/j.bios.2019.111593
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发表时间：
2019
影响因子：
12.6
通讯作者：
Yu Ruqin
中科院分区：
文献类型：
--
作者：
Zhao Weihua;Liu Mingbin;Li Hongbo;Wang Suqin;Tang Shasha;Kong Rong-Mei;Yu Ruqin
准确、灵敏地检测Pax-5a基因对急性白血病的早期诊断和预后判断具有重要意义。本文提出了一种无标记的电化学传感系统，用于检测急性白血病Pax-5a基因，该系统基于酶辅助信号放大以产生丰富的G-四链体/氯化血红素DNA酶。Pax-5a的存在可以打开作为模板的发夹探针（HP）。在限制性内切酶Nt.BbvCI和Klenow片段聚合酶的作用下，目的基因Pax-5a被循环打开HP;另一方面，产生大量的G-四链体序列。所得的G-四链体序列能够在氯化血红素存在下在电极表面上形成G-四链体/氯化血红素复合物。通过G-quadruplex/hemin络合物催化H2 O2还原，实现了Pax-5a的超灵敏无标记电化学检测，检测限可达4.6 fM。此外，该生物传感器具有良好的特异性和稳定性，在复杂底物环境中也具有优异的检测能力。因此，该传感器在生物分析和临床诊断方面显示出巨大的潜力。
Accurate and sensitive detection of the Pax-5a gene is of great importance in the early diagnosis and prognosis of acute leukaemia. Herein, a label-free electrochemical sensing system was proposed for the detection of the acute leukaemia Pax-5a gene based on enzyme-assisted signal amplification to generate abundant G-quadruplex/hemin DNAzyme. The presence of Pax-5a can open the hairpin probe (HP), which acts as a template. Under the action of the restriction enzymes Nt.BbvCI and Klenow fragment polymerase, the target gene Pax-5a is cycled to open the HP; On the other hand, a large number of G-quadruplex sequences are produced. The resulting G-quadruplex sequence is capable of forming the G-quadruplex/hemin complex on the surface of the electrode in the presence of hemin. The ultrasensitive label-free electrochemical detection of Pax-5a can be realized via the G-quadruplex/hemin complex-catalysed reduction of H2O2, and the detection limit was estimated to be as low as 4.6 fM. In addition, the biosensor has good specificity and stability, and also has excellent detection capabilities in a complex substrate environment. Therefore, the sensor shows great potential in bioanalysis and clinical diagnosis.