[Histonet] MMA embedding issue

[Herrick, James L. (Jim)]

Hello everyone,

I have embedded several rat femur/tibia specimens in MMA and am finding large holes (un-polymerized tissue) as I cut into the tissue - I am still in the soft tissue and not even into the bone yet (the specimens have large tumors). I placed a couple of the specimens into a 50°C oven for approximately 24 hours and then back into MMA for about a week with fresh changes and 60 minute vacuums each day. After cutting into the specimen again (following re-embedding), I am still finding soft un-polymerized tissue. Can I take these back to the liquid state with pure Methyl Methacrylate, then back into absolute alcohol, and once again back into methacrylate? I have done a large number of specimens similar and larger than these over the past few years without any trouble. If anyone has any knowledge and/or experience with this issue, your sharing would be greatly appreciated. Thanks again.

Jim Herrick
Senior Research Technologist
Department of Orthopedics
Bone Histomorphometry Core Lab
Phone: (507) 255-5946
fax: (507) 266-9451
Email: herrick.james <@t> mayo.edu
______________________
Mayo Clinic
200 First Street SW
Rochester, MN 55905
www.mayoclinic.org