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bioRxiv · 10.1101/657411

General and robust covalently linked graphene oxide affinity grids for high-resolution cryo-EM

Wang, F.·Liu, Y.·Yu, Z.·Li, S.·Cheng, Y.·Agard, D.
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Abstract

Despite their great potential to facilitate rapid preparation of quite impure samples, affinity grids have not yet been widely employed in single particle cryo-EM. Here, we chemically functionalize graphene oxide coated grids and use a highly specific covalent affinity tag system. Importantly, our polyethylene glycol spacer keeps particles away from the air-water interface and graphene oxide surface, protecting them from denaturation or aggregation and permits high-resolution reconstructions of small particles.

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Wang, F., Liu, Y., Yu, Z., Li, S., Cheng, Y., Agard, D.. 2019-06-02. General and robust covalently linked graphene oxide affinity grids for high-resolution cryo-EM. https://doi.org/10.1101/657411

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