Freezing Tissue Protocol
- Aluminum foil
- Plastic vial (about two-inches tall and one-inch wide)
- Dram bottle
- Wide-mouthed Thermoflask
- Applicator sticks (wooden)
- OCT (Optimum Cutting Temperature compound)
- Long forceps to hold the foil pocket and plastic vial
- Liquid nitrogen
- Razor blade
- Dental wax
- Permanent marker pen (to label the foil pocket)
- DERC Lab Service Request Form
- Use the dram bottle as a mold to make a foil pocket. Make sure that the pocket is labeled.
- Put a thin layer of OCT at the bottom of the foil pocket.
- Quickly place tissue in the OCT, tapping quickly with applicator if necessary to center and orient the specimen.
- Cover with OCT (about ½ inch).
- Place the foil pocket in the vial containing isopentane. The foil pocket should not float, but the isopentane should reach a level higher than the level of OCT.
- Set the vial with the aluminum pocket in liquid nitrogen. Do NOT let the liquid nitrogen spatter into the vial.
- The OCT will freeze from outside in. The tissue is completely frozen when a small peak forms in center of the OCT.
- Put the frozen block in a -20° C or -70° C freezer. If the specimen needs to be transferred, put it in dry ice.
Do not allow specimen to thaw.