EM-ICE High-pressure Freezer &
Automated Freeze-substitution System

Model Information

  • High-pressure Freezer: Leica EM-ICE with optogenetic stimulation
  • Automated Freeze-substitution System: Leica AFS-2
  • Cite in your manuscripts (example text): NIH Grant S10RR026445 (Institute:Research Resources [RR])
    Installed: Mar 2011; upgraded Jan 2016


  • Freeze specimen with 2000 atm pressure within milliseconds! Prevents formation of ice-crystals that damage cell membranes.

  • When frozen, crosslinking agents, particularly membrane-stabilizing reagents (e.g. osmium tetroxide), still work! Preservation is excellent!
  • Optogenetic stimulation (4 colors available):
    • Grow cells on special sapphire coverslips.
    • Special heater/environmental stage for cultured cells
    • Programmable delay between optogenetic stimulation and freezing.
    • After processing, EM images of cellular processes triggered by light.
  • Correlative light/fluorescence microscopy:
    • Grow cells on special sapphire coverslips.
    • Observe cells on light/fluorescence/confocal microscope (your choice!)
    • After walking down the hall, freeze within 10s!
    • After processing, compare light/fluorescence images with EM.


  • Preserving delicate membrane morphology:
    • nuclear membrane, nuclear pores
    • endoplasmic reticulum, both tubule, cisternae and plasma-membrane-associated ER (tubER, cecER, PM-ER)
  • Preserving large structures:
    • cell clusters (bacteria/biofilms)
    • whole Drosophila embryos