A colorimetric biosensor for detection of attomolar microRNA with a functional nucleic acid-based amplification machine
A colorimetric biosensor for detection of attomolar microRNA with a functional nucleic acid-based amplification machine
复制标题
一种比色生物传感器，用于使用基于功能性核酸的扩增机检测阿摩尔级 microRNA
DOI：
10.1016/j.talanta.2015.09.010
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发表时间：
2016-01-01
期刊：
影响因子：
6.1
通讯作者：
Ding, Shijia
中科院分区：
文献类型：
--
作者：
Li, Dandan;Cheng, Wei;Ding, Shijia
A functional nucleic acid-based amplification machine was designed for simple and label-free ultrasensitive colorimetric biosensing of microRNA (miRNA). The amplification machine was composed of a complex of trigger template and C-rich DNA modified molecular beacon (MB) and G-rich DNA (GDNA) as the probe, polymerase and nicking enzyme, and a dumbbell-shaped amplification template. The presence of target miRNA triggered MB mediated strand displacement to cyclically release nicking triggers, which led to a toehold initiated rolling circle amplification to produce large amounts of GDNAs. The formed GDNAs could stack with hemin to form G-quadruplex/hemin DNAzyme, a well-known horseradish peroxidase (HRP) mimic, for catalyzing a colorimetric reaction. The modified MB improved the stringent target recognition and reduced background signal. The proposed sensing strategy showed very high sensitivity and selectivity with a wide dynamic range from 10 aM to 1.0 nM, and enabled successful visual analysis of trace amount of miRNA in real sample by the naked eye. This rapid and highly efficient signal amplification strategy provided a simple and sensitive platform for miRNA detection. It would be a versatile and powerful tool for clinical molecular diagnostics. (C) 2015 Elsevier B.V. All rights reserved.
