The detection efficiency of low-dose cryo-4D STEM for biogenic crystals in frozen-hydrated samples
Year: 2025
Type: article
Abstract: elements such as vitrified ice. Numerical calculations refine our description by accounting for the effects of multiple scattering. Often underestimated, wide-angle tails associated with inelastic scattering play a crucial role for the detection of crystalline reflections in a thick ice matrix, common for cryo-electron microscopy. We show that guanine crystals as thin as a few nanometers can be detected with a fluence of just a few thousand electrons if the ice thickness is below one mean free path for inelastic scattering. The required fluence increases non-linearly with the embedding ice thickness, with a pronounced top-bottom effect regarding the location of the crystal in the sample. Energy-filtered recording significantly reduces the fluence needed for thicker samples. The low-dose simulations implemented here validate the analytical description while acknowledging its limitations due to abstraction from multiple scattering and beam spreading.
Source: Faraday Discussions
DOI: 10.1039/d5fd00027k
Authors: Lothar Houben, Zohar Eyal, Dvir Gur
Institution: Weizmann Institute of Science
Language: English
Subfield: Structural Biology
Domain: Life Sciences
Open Access status: hybrid
OpenAlex ID: W4411834534