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Amino and PEG-amino graphene oxide grids enrich and protect samples for high-resolution single particle cryo-electron microscopy.

ABSTRACT: Cryo-EM samples prepared using traditional methods often suffer from too few particles, poor particle distribution, 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.

SUBMITTER: Wang F

PROVIDER: S-EPMC7272056 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Amino and PEG-amino graphene oxide grids enrich and protect samples for high-resolution single particle cryo-electron microscopy.

Wang Feng F Yu Zanlin Z Betegon Miguel M Campbell Melody G MG Aksel Tural T Zhao Jianhua J Li Sam S Douglas Shawn M SM Cheng Yifan Y Agard David A DA

Journal of structural biology 20191219 2

Cryo-EM samples prepared using traditional methods often suffer from too few particles, poor particle distribution, 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 denatura ...[more]

PMID: 31866389

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