Frozen Sections

Excellent frozen section guide from Northwestern University and others

Frozen sectioning is the method of choice when paraffin processing may interfere with any downstream techniques. Common examples include Oil Red O staining for lipids (removed during paraffin processing) and antibodies whose epitopes are masked or destroyed by the ethanols and xylenes and heat involved with paraffin processing.

Fresh Frozen

  1. Tissue should be trimmed to specified region and cleaned of fat. Dab gently to remove any excess buffer.
  2. Embed in OCT and freeze in a dry ice/isopentane slurry- see Northwestern guide.
  3. Store frozen blocks at -80° and transport to lab on dry ice.

Fixed Frozen

  1. Fresh 4% Paraformaldehyde (PF) – perfuse animal or place tissue in fixative immediately. 10% NBF is also OK when fresh PF is not available.
  2. Fixation times will vary depending on tissue and antigen of interest. Test several before conducting full scale experiments.
  3. Core can provide 30% sucrose to cryoprotect fixed tissues then embed for you.

Cryosectioning (Frozen Sections)

  1.  Tissues will be cut at 5 – 50 microns- indicate your preference on form.
  2.  One section per slide unless otherwise requested.
  3.  Sections are placed on Superfrost/Plus slides (charged).
  4. Bring your own slide boxes or purchase from Core. Return to slide boxes for credit on future submissions.
  5. *Bring dry ice when picking up your frozen tissue and prepared slides.