On-demand controlled bidirectional DNAzyme path for ultra-sensitive heavy metal ion detection
Jing Xu1, Yujin Li1,2, Futing Wang2
1College of Chemistry and Chemical Engineering, Xinyang Normal University Xinyang 464000 China.
Chemical Science
|October 18, 2024
Summary
This study introduces a self-powered biosensor for detecting lead (Pb2+) and mercury (Hg2+) ions. Utilizing MoS2@CuS heterostructures and hybridization chain reaction (HCR), it achieves highly sensitive, quasi-simultaneous detection.
Area of Science:
- Electrochemistry
- Nanomaterials
- Biosensing
Background:
- Development of sensitive and selective biosensors for heavy metal detection is crucial for environmental monitoring and public health.
- Existing methods often require external power sources and lack simultaneous detection capabilities for multiple analytes.
- Molybdenum disulfide (MoS2) and copper sulfide (CuS) heterostructures offer unique electronic properties for enhanced biosensing applications.
Purpose of the Study:
- To construct a novel bidirectional, self-powered biosensor for the quasi-simultaneous detection of lead (Pb2+) and mercury (Hg2+) ions.
- To leverage MoS2@CuS heterostructures and hybridization chain reaction (HCR) for signal amplification and improved detection sensitivity.
- To demonstrate the biosensor's ability to detect Pb2+ and Hg2+ individually and simultaneously in a single device.
Main Methods:
- Fabrication of MoS2@CuS heterostructures to enhance electron transfer in a glucose-based self-powered biosensor.
- Design of specific DNAzyme sequences for selective recognition and cleavage of Pb2+ and formation of T-Hg2+-T structures for Hg2+.
- Integration of a hybridization chain reaction (HCR) strategy for signal amplification at the biocathode for Hg2+ detection.
Main Results:
- The MoS2@CuS heterostructures significantly improved electron transfer, boosting the biosensor's detection signal.
- The biosensor achieved highly sensitive detection of Pb2+ (LOD: 3.1 fM) and Hg2+ (LOD: 0.33 fM) within wide linear ranges.
- The system successfully demonstrated quasi-simultaneous detection of both Pb2+ and Hg2+ ions at the bioanode and biocathode, respectively.
Conclusions:
- A novel, self-powered, bidirectional biosensor capable of quasi-simultaneous Pb2+ and Hg2+ detection has been successfully developed.
- The synergistic use of MoS2@CuS heterostructures and HCR provides a robust platform for highly sensitive heavy metal ion monitoring.
- This work offers a promising approach for developing advanced electrochemical sensors for simultaneous environmental pollutant detection.
