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DNA four-way junction-driven dual-rolling circle amplification sandwich-type aptasensor for ultra-sensitive and specific detection of tumor-derived exosomes.
- Source :
-
Biosensors & Bioelectronics . Feb2024, Vol. 246, pN.PAG-N.PAG. 1p. - Publication Year :
- 2024
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Abstract
- There is an urgent need to accurately quantify tumor-derived exosomes, which have emerged as promising non-invasive tumor diagnostic biomarkers. Herein, a bispecific-aptamer sandwich-type gold nanoparticle-modified electrochemical aptasensor was developed based on a four-way junction (4-WJ)-triggered dual rolling circle amplification (RCA)-assisted methylene blue (MB)/G-quadruplex strategy for extremely specific and sensitive exosome detection. This aptamer/exosome/aptamer sandwich-type design contained a CD63-specific aptamer and a cancerous mucin-1 (MUC1) protein-specific aptamer. The CD63 aptamer modified on a gold electrode captured exosomes, and then the sandwich-type aptasensor was formed with the addition of the MUC1 aptamer. The MUC1 aptamer's 3′-end sequence facilitated the formation of 4-WJ, assisted by a molecular beacon probe and a binary DNA probe. Subsequently, a dual-RCA reaction was triggered by binding to two cytosine-rich circle DNA templates at both ends of 4-WJ. Ultimately, dual-RCA products containing multiple G-quadruplex conformations were generated with the assistance of K+ to trap abundant MB indicators and amplify electrochemical signals. The aptasensor exhibited high specificity, sensitivity, repeatability, and stability toward MCF-7-derived exosomes, with a detection limit of 20 particles/mL and a linear range of 1 × 102 to 1 × 107 particles/mL. Moreover, it showed excellent applicability in clinical settings to recover exosomes in normal human serum. Our aptasensor is anticipated to serve as a versatile platform for detecting various specific aptamer-based targets in biomedical and bioanalytical applications. • A DNA four-way junction-driven dual-rolling circle amplification sandwich-type electrochemical aptasensor has been engineered for ultra-sensitive and specific detection of tumor-derived exosomes. • This aptasensor could achieve MCF-7 exosome detection with a detection limit of 20 particles/mL and a dynamic range from 1 × 102 to 1 × 107 particles/mL. • This aptasensor could distinguish tumor-derived exosomes from nontumor-derived exosomes, enabling the distinction of neoplasia from non-neoplasia. [ABSTRACT FROM AUTHOR]
- Subjects :
- *APTAMERS
*EXOSOMES
*DNA probes
*TUMOR markers
*METHYLENE blue
*GOLD electrodes
Subjects
Details
- Language :
- English
- ISSN :
- 09565663
- Volume :
- 246
- Database :
- Academic Search Index
- Journal :
- Biosensors & Bioelectronics
- Publication Type :
- Academic Journal
- Accession number :
- 174412922
- Full Text :
- https://doi.org/10.1016/j.bios.2023.115841