An electron microscopic technique that involves freezing the biological sample in order to view the sample with the least possible distortion and the fewest possible artifacts. Abbreviated as cryo-EM.

In cryoelectron microscopy, the freezing of the sample is done in ethane slush to produce vitreous, or non-crystalline, ice. The frozen sample grid is then kept at liquid nitrogen temperature in the electron microscope and digital micrographs are collected with a camera.

The advantages of cryo-EM over traditional EM techniques include the preservation of the sample in a near-native hydrated state without the distortions from stains or fixatives needed for traditional EM. With image processing and averaging of multiple images, cyroelectron microscopy provides high resolution information (below 10 angstroms).

An angstrom is a metric unit of length equal to one ten billionth of a meter (or 0.0001 micron); used to specify wavelengths of electromagnetic radiation.