This device performs cell cryofixation (vitrification of cell pellets, tissue etc.) like the EMPACT-2 device but it can accept larger samples. i.e. the carriers are 3mm in diameter with a central cavity which is 2 mm in diameter with a depth of 100/150/200/ or 300 µm (A type carrier). The cavity of the carriers must be closed by a lid which has just a flat surface (B type carrier). We currently freeze C.elegans worms or Drosophila embryos (~150X600 µm) which typically require large carriers.
Moreover, it is possible to vitrify samples attached on sapphire coverslips (these are transparent disks 3mm in diameter) or samples that can be squeezed in between 2 sapphire disks separated by a spacer ring (~ 30/50 µm). This machine consumes more liquid nitrogen and is more “heavy” to use than the Leica EMPACT-2, however, success are guarantied with large or “difficult” samples. After freezing the samples are moved into an AFS device (AFS-1 or AFS-2) in order to process them for freeze substitution and plastic embedding (see AFS devices' pictures).