Our Wohlwend Compact 02 High Pressure Freezer is used to vitrify samples at -190°C at 2100 bars of pressure. Using this system, cultured cells, plant samples, as well as small tissue specimens and emulsions of yeast, bacteria and other microorganisms can be vitrified for high-resolution ultrastructural investigations.
Cryo immobilization is an approach that relies on the almost instantaneous immobilization of the biological processes within a tissue, or organism. Once all processes are arrested, the samples can be imaged under cryo conditions or processed at low temperatures for plastic embedded electron microscopy. This approach helps reduce alterations of sample ultrastructure, and improves the fidelity of sample preservation.
At the Instituto Gulbenkian de Ciência Electron Microscopy Facility there is currently no way to perform cryo-electron microscopy thus we use the Wohlwend HPF in combination with the Leica EM AFS2 to prepare fixed, resin embedded samples for high-resolution electron tomography, correlative light and electron microscopy (CLEM), immunogold labeling, or 2D electron microscopy of fragile structures.