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bioRxiv · 10.1101/813972

Amino and PEG-Amino Graphene Oxide Grids Enrich and Protect Samples for High-resolution Single Particle Cryo-electron Microscopy

Wang, F.·Yu, Z.·Betegon, M.·Campbell, M.·Aksel, T.·Zhao, J.·Li, S.·Douglas, S. M.·Cheng, Y.·Agard, D.
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Abstract

Cryo-EM samples prepared using the traditional methods often suffer from too few particles, poor particle distribution, or strongly biased orientation, or damage from the air-water interface. Here we report that functionalization of graphene oxide (GO) coated grids with amino groups concentrates samples on the grid with improved distribution and orientation. By introducing a PEG spacer, particles are kept away from both the GO surface and the air-water interface, protecting them from potential denaturation.

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Wang, F., Yu, Z., Betegon, M., Campbell, M., Aksel, T., Zhao, J., Li, S., Douglas, S. M., Cheng, Y., Agard, D.. 2019-10-22. Amino and PEG-Amino Graphene Oxide Grids Enrich and Protect Samples for High-resolution Single Particle Cryo-electron Microscopy. https://doi.org/10.1101/813972

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