Novel Method Reveals Sub-Microsecond Dynamics of DNA Molecules on Graphene
Researchers developed a new technique using graphene and fluorescence to observe rapid structural fluctuations in individual DNA molecules at sub-microsecond timescales. The method exploits distance-dependent energy transfer between graphene and fluorescent markers attached to vertically immobilized DNA strands. The findings advance understanding of how DNA dynamics are influenced by ionic conditions and structural defects, with implications for molecular biology and nanotechnology applications.
Scientists introduced an experimental approach for measuring extremely fast conformational changes in DNA by immobilizing oligonucleotides vertically on graphene surfaces and monitoring fluorescence intensity fluctuations caused by distance-dependent energy transfer. The technique successfully resolved dynamics at sub-microsecond resolution, revealing how ionic strength modulates DNA fluctuations and how structural defects such as nucleotide gaps or mismatches alter measured dynamics. The experimental observations were validated through complementary atomistic molecular dynamics simulations and kinetic Monte Carlo simulations, establishing quantitative agreement between theoretical predictions and experimentally observable timescales. This work addresses a longstanding challenge in molecular biology: directly observing the rapid thermal fluctuations that govern nucleic acid function at the single-molecule level. The findings have potential applications in understanding DNA-protein interactions, improving biosensors, and designing DNA-based nanostructures.
Limitations & open questions
The study does not discuss potential limitations of the graphene-based approach, such as whether the vertical immobilization or graphene proximity might artificially constrain or alter DNA dynamics compared to solution conditions, or whether the method is applicable to longer DNA sequences or double-stranded DNA under physiological conditions.
What different sources said
- bioRxivCenter
Resolving Sub-Microsecond Conformational Dynamics of Vertical Nucleic Acids on Graphene
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