Preparation of Graphene-Sandwiched Specimen for Cryo-EM
Abstract
Cryogenic electron microscopy (cryo-EM) enables high-resolution structural determination of macromolecules at near-atomic resolution through single particle analysis (SPA). However, air-water interface (AWI) effect, beam-induced charging effect and particle motion limit the full potential of this technique. The graphene sandwich method addresses these challenges by encapsulating specimens between two graphene layers, thereby improving cryo-EM data quality. This approach also expands the application prospects of graphene in electron microscopy. To simplify the implementation of this method, the present protocol details the stepwise process for preparing graphene-sandwiched specimens and collecting corresponding cryo-EM data.
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