Ratiometric Fluorescent Biosensor Based on Self-Assembled Fluorescent Gold Nanoparticles and Duplex-Specific Nuclease-Assisted Signal Amplification for Sensitive Detection of Exosomal miRNA.
Bioconjug Chem
; 33(9): 1698-1706, 2022 09 21.
Article
en En
| MEDLINE
| ID: mdl-35960898
ABSTRACT
The sensitive detection of cancer-associated exosomal microRNAs shows enormous potential in cancer diagnosis. Herein, a ratiometric fluorescent biosensor based on self-assembled fluorescent gold nanoparticles (Au NPs) and duplex-specific nuclease (DSN)-assisted signal amplification was fabricated for sensitive detection of colorectal cancer (CRC)-associated exosomal miR-92a-3p. In this biosensing system, the hairpin DNA modified with sulfhydryl and fluorescent dye Atto-425 at both ends is conjugated to fluorescent Au NPs through Au-S bonds, resulting in the quenching of Atto-425. The miR-92a-3p can open the hairpin of DNA and forms an miR-92a-3p/DNA heteroduplex, triggering the specific cleavage of DSN for the DNA in the heteroduplex. As a result, Atto-425 leaves the fluorescent Au NPs and recovers the fluorescence emission. The released miR-92a-3p can hybridize with another hairpin DNA and lead to a stronger fluorescence recovery of Atto-425 to form a signal amplification cycle. The stable fluorescence of Au NPs and the changing fluorescence of Atto-425 constitute a ratiometric fluorescent system reflecting the concentration of miR-92a-3p. This biosensor exhibits excellent specificity and can distinguish CRC patients from healthy individuals by detecting miR-92a-3p extracted from clinical exosome samples, showing the potential in CRC diagnosis.
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Técnicas Biosensibles
/
MicroARNs
/
Nanopartículas del Metal
Tipo de estudio:
Diagnostic_studies
Límite:
Humans
Idioma:
En
Revista:
Bioconjug Chem
Asunto de la revista:
BIOQUIMICA
Año:
2022
Tipo del documento:
Article
País de afiliación:
China