The standard procedures and protocols for the IU School of Medicine Electron Microscopy Core are provided here.
For all specimens brought for immunostaining (non-standard processing), the Core does not recommend having any Glutaraldehyde in the fixative. The Electron Microscopy Core recommends 4% Paraformaldehyde in a 0.1M buffer, either phosphate or cacodylate. The specimen should always be submitted in fixative—and not rinsed in a buffer. Paraformaldehyde does not cross link completely and will leach out of the tissue if left in buffer; therefore the tissue becomes unfixed and ruined.
Biohazardous specimens must always be brought in fixative.
For all specimens brought to the Electron Microscopy Core for standard processing, the Core recommends using the fixative provided by the lab. Fixation for electron microscopy is extremely important; if not done correctly, there is no way to correct it. Investigators who want to make up their own fixative must clear it with the Electron Microscopy Core first.