Direct Base-to-Base Transitions in ssDNA Revealed by Tip-Enhanced Raman Scattering

Xiu-Mei Lin; Tanja Deckert-Gaudig; Prabha Singh; Michael Siegmann; Stephan Kupfer; Zhenglong Zhang; Stefanie Gräfe; Volker Deckert

arXiv · 1604.06598

Direct Base-to-Base Transitions in ssDNA Revealed by Tip-Enhanced Raman Scattering

Xiu-Mei Lin·Tanja Deckert-Gaudig·Prabha Singh·Michael Siegmann·Stephan Kupfer·Zhenglong Zhang·Stefanie Gräfe·Volker Deckert

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Abstract

In the present contribution, specifically designed single-stranded DNA (ssDNA) sequences composed of adenine and cytosine were used as nanometric rulers to target the maximum achievable spatial resolution of tip-enhanced Raman spectroscopy (TERS) under ambient conditions. By stepping along a strand with a TERS tip, the obtained spectra allowed for a clear spectral discrimination including conformational information of the nucleobases, and even sharp adenine-cytosine transitions were detected repeatedly with a spatial resolution below 1 nm.

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Xiu-Mei Lin, Tanja Deckert-Gaudig, Prabha Singh, Michael Siegmann, Stephan Kupfer, Zhenglong Zhang, Stefanie Gräfe, Volker Deckert. 2016-04-22. Direct Base-to-Base Transitions in ssDNA Revealed by Tip-Enhanced Raman Scattering. https://arxiv.org/abs/1604.06598

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