TFS Titan Krios G4

A and B) Operator and user (Dr. Thomas Heidler and Aikaterini Filopoulou) at the Titan Krios 300 kV C). Micrograph of a vitrified tobacco mosaic virus (TMV) as viewed at 96 kX nominal magnification in Titan Krios 300 kV (picture credit: Dr. Olivera Korculanin)

Typical applications

The Krios G4 (Thermo-Fisher Scientific) is a 300 kV FEG cryo-electron microscope with X-FEG field emitter and a three-lens condenser system. The detector options are a Gatan BioContinuum energy filter mounted K3 direct electron detection camera and a bottom mounted Falcon 4(i) detector (FEI). Combined with fringe-free imaging (FFI) and aberration-free image shift (AFIS) in EPU, high-throughput imaging rates can be achieved. The microscope can be tuned set up for single-particle imaging, STEM and tomography experiments. Additionally, the Titan Krios is equipped with a Panther detector system (4 segments and annular dark-field detectors) that can be used for iDPC and HAADF-STEM imaging. The acquisition rate for a single particle sample on the Titan Krios is ~250-700 acquisitions/hour and we have achieved a maximal resolution of 1.7 Å with an apo-ferritin test sample.

Technical specifications

Operating voltage	80 kV – 300 kV Alignments for 120, 200 and 300kV
TEM magnification range	Up to 195,000X with Falcon IV (0.38 Å/pixel) 165,000X with K3 detector (0.52 Å/pixel and 0.26 Å/pixel in super res mode)
Ion source	X-FEG
Operating conditions	Cryo / liquid nitrogen conditions
Detector	Ceta 4kx4k 16M camera Gatan K3 camera (including energy filter BioContinuum GIF) Falcon 4 camera Panther segmented STEM detector Fischione annular dark-field STEM detector
Configuration	Autoloader with up to 12 grids Automated data acquisition at cryo-conditions Volta phase plate
Stage	Computerized 4-axes specimen stage with ±70° alpha tilt Dual tilt cryostage
Software	TIA, EPU, Velox, SerialEM, Maps, Tomo