Back to Search
Start Over
DNA synergistic enzyme-mediated cascade reaction for homogeneous electrochemical bioassay
- Source :
- Biosensors and Bioelectronics. 142:111510
- Publication Year :
- 2019
- Publisher :
- Elsevier BV, 2019.
-
Abstract
- Enzyme-mediated cascade reaction is applied to amplify signal and decrease the background because enzyme can catalyze inactive substrates into active substrates to generate the signal. In this work, Au nanoparticles, as signal probe, are used to load DNA probe and ALP for dual signal amplification. Based on enzyme-mediated cascade reaction, a homogeneous biosensor is constructed for bioassay by employing thrombin as target molecule. When the target is present in the solution, ALP catalyzes the PPi into Pi and then reacts with molybdate in conjunction with Pi in the DNA backbone to produce redox precipitates on the surface of the reduced graphene oxide modified electrode with the help of magnetic separation. Compared with the conventional heterogeneous biosensor, the immobilization-free strategy, proposed in this homogeneous biosensor, improves the sensitivity because of its lower steric hindrance. As a result, this biosensor displayed a great sensitivity with a wide linear range from 1 fM to 10 nM and a detection limit of 0.26 fM, providing a promise and easy operating method for various proteins detection.
- Subjects :
- Biomedical Engineering
Biophysics
Metal Nanoparticles
Nanoparticle
Biosensing Techniques
02 engineering and technology
01 natural sciences
Redox
chemistry.chemical_compound
Cascade reaction
Limit of Detection
Electrochemistry
Humans
Molybdenum
Detection limit
Hybridization probe
010401 analytical chemistry
Thrombin
Electrochemical Techniques
General Medicine
Alkaline Phosphatase
021001 nanoscience & nanotechnology
Combinatorial chemistry
0104 chemical sciences
chemistry
Linear range
Graphite
Gold
DNA Probes
0210 nano-technology
Oxidation-Reduction
Biosensor
DNA
Biotechnology
Subjects
Details
- ISSN :
- 09565663
- Volume :
- 142
- Database :
- OpenAIRE
- Journal :
- Biosensors and Bioelectronics
- Accession number :
- edsair.doi.dedup.....2d990f0a564cdbdd978aaff0eaee96f3