State Key Laboratory of Food Science and Technology,;School of Food Science and Technology, National Engineering Research Center for Functional Food, Synergetic Innovation Center of Food Safety and Quality Control , Jiangnan University , Wuxi , Jiangsu 214122 , People's Republic of China.
Guangdong Provincial Key Laboratory of Food Quality and Safety , South China Agricultural University , Guangzhou 510642 , Guangdong Province , People's Republic of China.
Anal Chem. 2018 Mar 6;90(5):3099-3108. doi: 10.1021/acs.analchem.7b04051. Epub 2018 Feb 16.
MicroRNAs (miRNAs), a kind of single-stranded small RNA molecule, play significant roles in the physiological and pathological processes of human beings. Currently, miRNAs have been demonstrated as important biomarkers critically related to many diseases and life nature, including several cancers and cell senescence. It is valuable to establish sensitive assays for monitoring the levels of intracellular up-regulated/down-regulated miRNA expression, which would contribute to the early prediction of the tumor risk and cardiovascular disease. Here, an oriented gold nanocross (AuNC)-decorated gold nanorod (AuNR) probe with "OFF-enhanced ON" fluorescence switching was developed based on fluorescence resonance energy transfer and surface enhanced fluorescence (FRET-SEF) principle. The nanoprobe was used to specifically detect miRNA in vitro, which gave two linear responses represented by the equation F = 1830.32 log C + 6349.27, R = 0.9901, and F = 244.41 log C + 1916.10, R = 0.9984, respectively, along with a detection limit of 0.5 aM and 0.03 fM, respectively. Furthermore, our nanoprobe was used to dynamically monitor the expression of intracellular up-regulated miRNA-34a from the HepG2 and H9C2 cells stimulated by AFB1 and TGF-β1, and the experimental results showed that the new probe not only could be used to quantitively evaluate miRNA oncogene in vitro, but also enabled tracking and imaging of miRNAs in living cells.
微小 RNA（miRNAs）是一种单链小分子 RNA，在人类的生理和病理过程中发挥着重要作用。目前，miRNAs 已被证明是与多种疾病和生命性质密切相关的重要生物标志物，包括几种癌症和细胞衰老。建立灵敏的检测方法来监测细胞内上调/下调 miRNA 表达水平具有重要价值，这将有助于肿瘤风险和心血管疾病的早期预测。在这里，我们基于荧光共振能量转移和表面增强荧光（FRET-SEF）原理，开发了一种具有“关闭增强开启”荧光切换功能的定向金纳米交叉（AuNC）修饰金纳米棒（AuNR）探针。该纳米探针可用于体外特异性检测 miRNA，其提供了两个线性响应，由方程 F = 1830.32 log C + 6349.27，R = 0.9901 和 F = 244.41 log C + 1916.10，R = 0.9984 表示，检测限分别为 0.5 aM 和 0.03 fM。此外，我们的纳米探针还用于动态监测 AFB1 和 TGF-β1 刺激的 HepG2 和 H9C2 细胞中内源性上调 miRNA-34a 的表达，实验结果表明，该新探针不仅可以用于体外定量评估 miRNA 致癌基因，还能够对活细胞中的 miRNAs 进行跟踪和成像。
