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Electrochemical DNA Biosensing via Electrochemically Controlled Reversible Addition-Fragmentation Chain Transfer
Qiong Hu1,2, Jinming Kong1, Dongxue Han2
1School of Environmental and Biological Engineering , Nanjing University of Science and Technology , Nanjing 210094 , People's Republic of China.
ACS Sensors
|January 9, 2019
Summary
This study presents a novel electrochemical DNA biosensor for highly sensitive and selective detection of DNA fragments. It utilizes electrochemically controlled reversible addition-fragmentation chain-transfer (eRAFT) polymerization for signal amplification, achieving attomolar detection limits for disease diagnostics.
Area of Science:
- Biosensors
- Electrochemistry
- Molecular Diagnostics
Background:
- Sensitive detection of biological molecules is crucial for disease diagnosis and surveillance.
- Existing methods often face limitations in sensitivity, selectivity, or complexity.
Purpose of the Study:
- To develop an ultrasensitive and highly selective electrochemical DNA biosensor.
- To employ electrochemically controlled reversible addition-fragmentation chain-transfer (eRAFT) polymerization for signal amplification.
Main Methods:
- Peptide nucleic acid (PNA) probes immobilized on a gold electrode for DNA recognition.
- Phosphate-Zr4+-carboxylate chemistry for labeling chain-transfer agents (CTAs).
- eRAFT polymerization initiated electrochemically using aryl diazonium salts and ferrocenylmethyl methacrylate monomer.
Main Results:
- Achieved an attomolar detection limit (4.1 aM) for target DNA fragments.
- Demonstrated a wide linear range from 10 aM to 10 pM (R² = 0.998).
- Exhibited high selectivity and applicability in complex serum samples.
Conclusions:
- The developed electrochemical DNA biosensor offers high efficiency, selectivity, and sensitivity.
- The eRAFT polymerization strategy provides significant signal amplification.
- This low-cost, easy-to-operate biosensor shows great promise for real-world disease diagnosis and surveillance applications.
Keywords:
DNA biosensorelectrochemicalelectrochemically controlled radical polymerizationpeptide nucleic acidreversible addition−fragmentation chain-transfer polymerizationsignal amplificationMore Related Videos
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