The Krios G4 cryogenic electron microscope (cryo-EM) allows for the rapid collection of atomic resolution data for beam-sensitive samples using automated procedures and low electron doses. This 300kV three-condenser X-FEG microscope can be operated in TEM or STEM modes and is equipped with a Ceta 4K x 4K 16M CMOS camera, a Falcon3EC direct electron detector, and a Gatan Continuum electron energy loss spectrometer. High-throughput data collection and dose monitoring can be achieved with a 12-sample autoloader system, aberration-free image shift (AFIS) alignment, and automated operation software in TEM and STEM mode. Offload data storage arrays to accommodate multi-TB datasets, high-performance workstations, reconstruction software for single particle analysis (SPA) and tomography (ET) data, and 3D data visualization software are maintained and available.
Specifications
- Source and Accelerating voltage
- X-FEG (extreme high-brightness field emission gun)
300kV
Sample loading and Temperature
- Automated and contamination-free loading of cassettes for up to 12 grids
- Highly controlled and monitored at liquid nitrogen temperatures with automated cryo-cycling and cool-down scheduling
Lenses and Stage
- Automatic condenser, objective, and SA apertures
- 3-condenser-lens system for automated, continuous, parallel illumination
- Symmetric constant power C-TWIN objective lens with a wide-gap pole piece (11mm)
- Computerized 4-axis specimen stage with +/- 70° alpha tilt
- Cryo-stage with single axis holder for optimized stability and drift performance
Detectors
- Ceta 4K x 4K CMOS Detector
- Falcon3EC Direct Electron Detector (counting and linear mode)
- Volta Phase Plate
- On-Axis BF/DF Detectors
- HAADF STEM Detector
- Gatan Continuum Electron Energy Loss Spectrometer
Automated software for alignment and data collection
- Automated alignment and sample atlasing for low-mag, full grid analysis
- Thermofisher EPU
- Tomo5 (STEM and TEM)
- SerialEM
- VELOX
- TIA
Workstations
- DGX Box – 16GPU/500CPU
- Lamba Blade – 8GPU/250CPU
Data Reconstruction, Refinement, Modelling, and Visualization Software
- CryoSparc
- Scipion Package Manager
- IMOD
- RELION4
- EMAN2
- CCP4 Program Suite
- Phenix
- Coot
- AlphaFold2 (CoLab)
- ChimeraX
- PyMol
