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Sequence-specific and Selective Recognition of Double-stranded RNAs over Single-stranded RNAs by Chemically Modified Peptide Nucleic Acids
Published on: September 21, 2017
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Sequence-controlled chiral induced spin selectivity effect in ds-DNA
Neeraj Bangruwa1, Suryansh1, Mayra Peralta2,3
1Department of Physics and Astrophysics, University of Delhi, New Delhi 110007, India.
The Journal of Chemical Physics
|July 24, 2023
Summary
Chiral-induced spin selectivity (CISS) in double-stranded DNA influences electron lifetimes and spin polarization. This DNA spin effect impacts electron transfer and could enable novel DNA sensors.
Area of Science:
- Molecular Biophysics
- Nanotechnology
- Quantum Chemistry
Background:
- Chiral-induced spin selectivity (CISS) is a phenomenon where chiral molecules induce spin polarization in charge carriers.
- Double-stranded DNA (ds-DNA) possesses chirality, suggesting potential for CISS effects.
- Understanding sequence-dependent spin transport in DNA is crucial for molecular electronics and sensing.
Purpose of the Study:
- To investigate sequence-dependent chiral-induced spin selectivity (CISS) in double-stranded DNA (ds-DNA).
- To quantify the impact of CISS on photo-excited electron lifetimes and spin polarization.
- To explore the potential of CISS in ds-DNA for developing next-generation DNA sensors.
Main Methods:
- Utilized time-correlated single-photon counting and electrochemical impedance spectroscopy.
- Employed tight-binding calculations combined with Green's function formalism for transport simulations.
- Analyzed the influence of CISS on electron lifetimes and spin-polarized electron yield in ds-DNA systems.
Main Results:
- Observed a significant difference in average electron decay time (345 ps) due to CISS in ds-DNA for opposite spin polarities.
- Demonstrated a reduction of over 35% in spin-polarized electron yield from perfect ds-DNA to DNA with point mutations.
- Experimental findings were supported by theoretical simulations using tight-binding and Green's function methods.
Conclusions:
- Established a fundamental understanding of sequence-specific, spin-dependent electron transfer through ds-DNA.
- Highlighted the role of CISS in modulating electron transport properties of DNA.
- Paved the way for the development of advanced, spin-based DNA sensors leveraging CISS effects.
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