Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7233135 | Biosensors and Bioelectronics | 2014 | 6 Pages |
Abstract
A novel electrochemical biosensing strategy was developed for ultrasensitive and specific detection of target DNA using a cascade signal amplification based on molecular beacon (MB) mediated circular strand displacement (CSD), rolling circle amplification (RCA), biotin-strepavidin system, and enzymatic amplification. The target DNA hybridized with the loop portion of MB probe immobilized on the gold electrode and triggered the CSD, leading to multiple biotin-tagged DNA duplex. Furthermore, via biotin-streptavidin interaction, the RCA was implemented, producing long massive tandem-repeat DNA sequences for binding numerous biotinylated detection probes. This enabled an ultrasensitive electrochemical readout by further employing the streptavidin-alkaline phosphatase. The proposed biosensor showed very high sensitivity and selectivity with a dynamic response range from 1Â fM to 100Â pM. The proposed strategy could have the potential for applying in clinical molecular diagnostics and environmental monitoring.
Related Topics
Physical Sciences and Engineering
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Authors
Wei Cheng, Wei Zhang, Yurong Yan, Bo Shen, Dan Zhu, Pinhua Lei, Shijia Ding,