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arXiv · 1908.09374

Direct visualization of charge transport in suspended (or free-standing) DNA strands by low-energy electron microscopy

Tatiana Latychevskaia·Conrad Escher·William Andregg·Michael Andregg·Hans-Werner Fink
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Abstract

Low-energy electrons offer a unique possibility for long exposure imaging of individual biomolecules without significant radiation damage. In addition, low-energy electrons exhibit high sensitivity to local potentials and thus can be employed for imaging charges as small as a fraction of one elementary charge. The combination of these properties makes low-energy electrons an exciting tool for imaging charge transport in individual biomolecules. Here we demonstrate the imaging of individual deoxyribonucleic acid (DNA) molecules at the resolution of about 1 nm with simultaneous imaging of the charging of the DNA molecules that is of the order of less than one elementary charge per nanometer. The cross-correlation analysis performed on different sections of the DNA network reveals that the charge redistribution between the two regions is correlated. Thus, low-energy electron microscopy is capable to provide simultaneous imaging of macromolecular structure and its charge distribution which can be beneficial for imaging and constructing nano-bio-sensors.

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Tatiana Latychevskaia, Conrad Escher, William Andregg, Michael Andregg, Hans-Werner Fink. 2019-08-25. Direct visualization of charge transport in suspended (or free-standing) DNA strands by low-energy electron microscopy. https://doi.org/10.1038/s41598-019-45351-4

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