Microcrystal electron diffraction (MicroED) involves collecting a sequence of diffraction images from a continuously rotating microcrystal in a transmission electron microscope. Due to the small size of these crystals, the resulting diffraction patterns typically feature weak, low-intensity spots. Recent advances in direct electron-counting detectors have significantly improved signal...
Ten years on from the “resolution revolution”, molecular structure determination using electron cryomicroscopy (cryoEM) is poised in 2025 or early 2026 to surpass X-ray crystallography as the most used method for experimentally determining new structures [1]. But the technique has not reached the physical limits set by radiation damage and the signal-to-noise ratio in individual images of...
Beam damage to biological specimens is more troublesome in the TEM than in x-ray imaging (where the spatial resolution is more modest) despite the stronger diffraction signal provided by electrons [1]. One solution has been to treat tissue (and other) specimens with heavy-metal stain but the preference is to use unstained samples and phase contrast, while cooling the sample to reduce damage...
The benefits of reducing the data collection temperature for electron cryomicroscopy (cryo-EM) from liquid-nitrogen temperatures to liquid-helium temperatures have been debated over many years. A physical theory of dose-dependent information loss in cryo-EM was presented for imaging vitrified aqueous biological specimens at liquid-nitrogen temperatures [1], but extending this to liquid-helium...
