Optical interference for the guidance of cryogenic focused ion beam milling beyond the axial diffraction limit.

ABSTRACT: Cryogenic focused ion beam (Cryo-FIB) milling has become a standard step in the cryogenic electron tomography (Cryo-ET) workflow and is required to thin cells to electron-semitransparency. However, this destructive process removes the vast majority of the cellular material and raises a critical question: what thin section should be preserved for Cryo-ET analysis? Using a tri-coincident cryogenic FIB-SEM-LM system, we identify an interferometric optical response that can be used for targeting lamella production to fluorescently labeled structures with accuracy beyond the diffraction limit. Here we demonstrate this approach using synthetic samples of fluorescent beads embedded in micron-scale droplets of amorphous ice. We then apply the approach to capture virions inside host cells. Successf

SUBMITTER: Sica AV 

PROVIDER: S-EPMC12804907 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature