GraFix: sample preparation for single-particle electron cryomicroscopy.
We developed a method, named GraFix, that considerably improves sample quality for structure determination by single-particle electron cryomicroscopy (cryo-EM). GraFix uses a glycerol gradient centrifugation step in which the complexes are centrifuged into an increasing concentration of a chemical fixation reagent to prevent aggregation and to stabilize individual macromolecules. The method can be used to prepare samples for negative-stain, cryo-negative-stain and, particularly, unstained cryo-EM.
D020285:Cryoelectron Microscopy / Q000379:methods*; D007089:Image Enhancement / Q000379:methods*; D013048:Specimen Handling / Q000379:methods*; D016707:Tissue Fixation / Q000379:methods*