Enzyme-Free Electrochemical Biosensor Based on Localized DNA Cascade Displacement Reaction and Versatile DNA Nanosheets for Ultrasensitive Detection of Exosomal MicroRNA.
|
| Abstract |
MicroRNA existing in exosomes (exo-miRNA) is a crucial and reliable biomarker for cancer screening and diagnosis. However, accurate detection of ultralow exo-miRNA amounts in real samples remains a challenge. Herein, a robust and ultrasensitive electrochemical biosensor was developed based on localized DNA cascade displacement reaction (L-DCDR) and versatile DNA nanosheets (DNSs) for enzyme-free analysis of exo-miRNA. The target activated L-DCDR repeatedly by consecutive toehold-mediated strand displacement, which released plentiful P strands to hybridize with capture probes immobilized on the electrode surface and DNS tags, generating an amplified electrochemical signal for the detection of exo-miRNA. The DNS could label-free load various electroactive molecules. The electrochemical biosensor revealed high sensitivity ranging from 0.1 fM to 1 nM with a limit of detection of 65 aM and good specificity. The constructed biosensor was demonstrated to be able to detect exo-miRNA derived from gastric cancer cell line (SGC-7901) and gastric cancer patients. In addition, the developed biosensor possessed several considerable advantages including simple substrate assembly, improved reaction rate, and high signal-to-noise ratio. Therefore, this strategy has great potential in bioanalysis and clinical diagnostics.
|
|---|---|
| Authors | Ping Liu, Xiaoqing Qian, Xinmin Li, Lu Fan, Xinyu Li, Daxiang Cui, Yurong Yan |
| Journal | ACS applied materials & interfaces (ACS Appl Mater Interfaces) Vol. 12 Issue 40 Pg. 45648-45656 (Oct 07 2020) ISSN: 1944-8252 [Electronic] United States |
| PMID | 32915531 (Publication Type: Journal Article) |
| Chemical References |
|
| Topics |
|
Join CureHunter, for free Research Interface BASIC access!
Realize the full power of the drug-disease research graph!