Protocol Online logo
Top : Forum Archives: : Immunology and Histology

Gluteraldehyde fixation on tissue - How long is too long? - (Oct/17/2007 )

I am trying to do a simple HE staining on some gills (very small, very little cartilaginous/hard parts inside). I have already processed (typical dehydration with ethanol, then toluene, paraffin) and am currently trying to cut sections with a microtome. The samples are crumbling despite trying techniques such as faster cut, sharper blade, heating up sample, etc.

I'm thinking the problem may be with the fixation process. These samples were in gluteraldehyde for about a month and a half before processing. Could this cause the crumbling of the tissue that I am seeing?


Its not fixation's fault. have you thought about to increase the section thickness? Maybe the difference in hardness between your tissue sample and paraffin is too great? If so, would epon resin embedding be better?

You may find more helpful info at


I would agree with genehunter that glutaraldehyde is not to blame. I have sectioned brains which have been fixed for months and they do cut fine.

Try to wet the paraffin section with water, this could help cut properly. Or you may have to adjust size of the sections.