A sensitive colorimetric assay system for nucleic acid detection based on isothermal signal amplification technology
A sensitive colorimetric assay system for nucleic acid detection based on isothermal signal amplification technology
复制标题
基于等温信号放大技术的灵敏核酸检测比色分析系统
DOI：
10.1007/s00216-017-0425-4
复制
发表时间：
2017-08-01
影响因子：
4.3
通讯作者：
Guan, Yifu
中科院分区：
文献类型：
--
作者：
Hu, Bo;Guo, Jing;Guan, Yifu
快速准确地检测生物系统中的microRNA具有重要意义。在这里，我们报告了一个视觉比色分析，具有高放大能力和高选择性的滚环扩增（RCA）方法和简单和方便的金纳米粒子作为信号指示剂的发展。设计的挂锁探针识别目标miRNA并被环化，然后作为模板将目标miRNA延伸成许多核苷酸序列串联重复的长单链核苷酸链。接下来，RCA产物与标记在金纳米颗粒上的寡核苷酸杂交。这种相互作用导致金纳米颗粒聚集，并且系统的颜色根据miRNA的丰度从酒红色变为深蓝色。荧光强度与靶寡核苷酸含量在0.3-300 pM范围内呈线性关系，沿着，检测限为0.13 pM（n= 7），相对标准偏差为3.9%（30 pM，n= 9）。本方法提供了一种简单、快速和准确的目视比色测定法，其允许对生物重要样品中感兴趣的DNA和RNA核苷酸进行灵敏的生物检测和生物分析。
Rapid and accurate detection of microRNAs in biological systems is of great importance. Here, we report the development of a visual colorimetric assay which possesses the high amplification capabilities and high selectivity of the rolling circle amplification (RCA) method and the simplicity and convenience of gold nanoparticles used as a signal indicator. The designed padlock probe recognizes the target miRNA and is circularized, and then acts as the template to extend the target miRNA into a long single-stranded nucleotide chain of many tandem repeats of nucleotide sequences. Next, the RCA product is hybridized with oligonucleotides tagged onto gold nanoparticles. This interaction leads to the aggregation of gold nanoparticles, and the color of the system changes from wine red to dark blue according to the abundance of miRNA. A linear correlation between fluorescence and target oligonucleotide content was obtained in the range 0.3–300 pM, along with a detection limit of 0.13 pM (n= 7) and a RSD of 3.9% (30 pM,n= 9). The present approach provides a simple, rapid, and accurate visual colorimetric assay that allows sensitive biodetection and bioanalysis of DNA and RNA nucleotides of interest in biologically important samples.Graphical abstractThe colorimetric assay system for analyzing target oligonucleotides