High Pressure Freezer
The Leica EM PACT2 high pressure freezer with Rapid Transfer System (RTS) is a high pressure freezing system for vitrifying samples up to 200µm in thickness without the artefacts of chemical fixation.
- Chemical fixation via diffusion is a slow process that may take minutes to hours. Furthermore, not all cell components will react with fixatives at equal rates, or to equal degrees. As a result, some cell components may be lost or rearranged.
- Physical immobilization of all cell components by ultrarapid freezing has been shown to be superior to conventional chemical fixation at room temperature.
- The Leica EM PACT2 makes it possible to observe aqueous biological and industrial samples in their near-native state while preserving high-resolution information of EM immunocytochemistry, frozen hydrated sections, and freeze fractured samples.
- The Leica EM rapid transfer system (RTS) allows correlative LM/EM experiments (CLEM), taking a live specimen from a light microscope (e.g. confocal) to freezing in less than 5 seconds.
- High pressure freezing may be used to prepare samples for cryoTEM, cryoSEM, for subsequent preparation of freeze-fracture replicas for TEM, and for freeze-substitution. It has also been successfully applied to non-biological materials such as latex emulsions and inks for cryoSEM examination.
This instrument was purchased with funding from an NIH S10 Shared Instrument grant award.
Specimen Prepared by High Pressure Freezing
HPF/AFS in unicryl
HPF/AFS in lowicryl