Equipment

The 120kV Tecnai Spirit is equipped with a tungsten filament electron source, and a 2kx2k UltraScan CCD camera. It is primarily available for screening negative-stained samples, but is capable of cryo-electron microscopy.

The F20 can operate at 120kV or 200kV. It has a field emission gun (FEG) source of electrons, which provides better coherence. It is used for basic electron cryomicroscopy of moderate resolution projects, or for higher-resolution negative-stain data collection. It is equipped with a 4k x 4k UltraScan CCD camera.

The Titan Krios has an XFEG electron source and operates at 300kV.

This microscope not only has a Falcon IIIEC direct electron detector camera, but a K3/GIF has recently been added, which avoids loss of data quality which can occur with other detectors and is more sensitive. This detector effectively increases resolution by recording sharper images and compensating for sample movement while it is imaged.

It has been designed to be extremely stable by environmentally isolating the system from external vibrations and temperature changes. Thus grids are robotically transferred into the beam and the user operates the instrument from a separate room.

The improved system provides superior controllability and reproducibility, and the ability to collect data on a single grid for up to a week. Traditionally, EM grids have to be changed manually every 4-6 hours.

Up to ten sample grids can be loaded.

For suitable specimens, computational analysis of images from the Krios with a direct detector generates atomic models that rival those calculated by X-ray crystallography and NMR spectroscopy.

This instrument determined the structure of a highly stable virus, as published in Science

The Glacios is a 200kV electron microscope with a cryo Autoloader, XFEG electron source and Falcon4 direct electron detector. It is ideal for screening cryo samples and preliminary data collection for cryoEM and cryoET.