Signal-On Fluorescence Biosensor for Highly Sensitive Detection of miRNA-21 Based on DNAzyme Assisted Double-Hairpin Molecular Beacon.

Content Provider	Europe PMC
Author	Fang, Chenxin Yang, Yuxing Zou, Shuhao Ouyang, Ping Qing, Yang Han, Jialun Li, Haiyu Wang, Zhencui Du, Jie
Copyright Year	2022
Abstract	Although miRNAs exist in small quantities in the human body, they are closely related to the abnormal expression of genes in diseases such as tumors. Therefore, sensitive detection of miRNAs is very important for the prevention and treatment of various tumors and major diseases. The purpose of this study is to develop a label-free sensing strategy based on the co-action of double-hairpin molecular beacons and deoxyribozymes (DNAzymes) for highly sensitive detection of miRNA-21. The target miRNA-21 promotes the assembly of DNAzyme with a complete catalytic core region. At the presence of Mg2+, DNAzyme cuts a substrate into short chains, which open the double hairpin molecular beacon, and then form G-quadruplexs at both ends, specifically binding more ThT to generate a amplified fluorescent signal. The cut substrate will be replaced by the uncut ones in the next stage, increasing the concentration of reactants, and thus further improving the fluorescence intensity. This DNAzyme assisted double hairpin molecular beacon has a certain degree of discrimination for substances with single base mismatches, and the detection limit of miRNA-21 is 0.13 pM, lower than that of the many other analysis. Further, this detection has good selectivity and sensitivity in serum. Therefore, this strategy provides a simple, fast and low-cost platform for the sensitive detection of miRNA-21, having potential applications in early cancer diagnosis.
Volume Number	12
PubMed Central reference number	PMC9139022
Issue Number	5
PubMed reference number	35624579
Journal	Biosensors (Basel)
e-ISSN	20796374
DOI	10.3390/bios12050276
Language	English
Publisher	MDPI
Publisher Date	2022-04-27
Access Restriction	Open
Rights License	Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). © 2022 by the authors.
Subject Keyword	signal amplification fluorescent biosensor DNAzyme miRNA detection high sensitivity
Content Type	Text
Resource Type	Article
Subject	Clinical Biochemistry Instrumentation Medicine Biomedical Engineering Engineering Analytical Chemistry Biotechnology