Development of a Side Entry High Tilt Cryotransfer Stage for Tomographic Applications

Abstract

Three-dimensional electron microscopic imaging, or electron tomography, involves the reconstruction of individual objects from projection data collected over a large range of specimen tilts. Practical limitations of tomography are set by the range of specimen tilt available to generate projection data. In terms of tilt range, current data sets typically cover a range of up to +/-700° of tilt.When used for applications requiring high tilt such as tomography, problems with specimen holder designs which use circular 3mm diameter grids include restricted field of view created by the standard mesh pattern of commercially available specimen grids. The standard square or hexagonally patterned support grids provide minimal area between grid bars to view a sample at high tilt. The width of the specimen clamping device and holder tip blade also limit the useable grid area to the center of the specimen when the holder is at high tilt positions.