Freeze Substitution (FS)

This technique allows to replace water with a resin in freeze-fixed biological specimen at a temperature low enough to avoid the formation of destructive ice crystals. The idea is to preserve the ultrastructure of a biological sample close to the “native” state by avoiding chemical fixation and to circumvent the damaging effects observed after ambient temperature dehydration. In our facility we have the possibility to perform FS on samples frozen with a high pressure freezer for further EM analysis.