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Real-Time Modulation of DNA Conductivity via Magnetic Fields Studied by C-AFM
Mingyan Gao1,2,3,4, Jing Hu1,2, Mengnan Liu1,2
1Key Laboratory of Architectural Cold Climate Energy Management, Ministry of Education, Jilin Jianzhu University, Changchun, China.
Microscopy Research and Technique
|February 2, 2026
Summary
Researchers explored DNA conductivity using magnetic fields. They found that magnetic fields can dynamically tune DNA
Area of Science:
- Molecular electronics
- Nanotechnology
- Biophysics
Background:
- DNA's charge transport properties offer potential for molecular electronics.
- Real-time dynamic regulation of DNA conductivity is a significant challenge.
Purpose of the Study:
- To investigate the real-time conductivity of DNA under magnetic field modulation.
- To explore noncontact strategies for tuning DNA-based nanoelectronic devices.
Main Methods:
- Utilized a conductive atomic force microscopy (C-AFM) system.
- Integrated magnetic field modulation (DC and AC) with C-AFM.
- Measured conductivity of lambda-DNA (λ-DNA) on gold-coated mica substrates.
Main Results:
- DNA molecular height positively correlated with tunneling current.
- Single double-stranded DNA (dsDNA) showed a median current of -1.27 pA.
- Multi-stranded DNA fibers exhibited enhanced conductivity (median current: -3.71 pA).
- DC magnetic fields suppressed conductivity due to the Lorentz force effect.
- AC magnetic fields at 25 MHz showed frequency- and field-dependent modulation of conductivity.
Conclusions:
- Direct experimental evidence for real-time magnetic modulation of DNA transverse tunneling conductance.
- Demonstrated a noncontact strategy for tuning DNA conductivity.
- Findings support the use of DNA in tunable nanoelectronic devices.
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