Resin Embedding

A forum to ask questions, post setups, and generally discuss anything having to do with photomacrography and photomicroscopy.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

Gearhead
Posts: 14
Joined: Tue Mar 23, 2021 12:11 pm
Location: Indianapolis, Indiana, USA

Resin Embedding

Post by Gearhead »

I’ve recently tried using resin embedding of plant and fungus specimens because of what I understand are several advantages over wax. The specimen doesn’t need to be completely dehydrated because resin such as LR White is miscible with water. And supposedly the sections can be stained without removing the resin, unlike wax which needs to be removed with a solvent like xylene. I’ve read that LR White embedded specimens for light microscopy can be sectioned on a standard microtome using a good steel blade.
I’m just starting out with resin. I wonder what experience others have had with it. I find that the LR White becomes very hard and brittle. It’s difficult to cut with a good steel microtome blade. Is there a way to control how hard the resin gets when it cures? Are there particular techniques that make sectioning easier? Special blades that work better? I know that a glass knife on an ultra microtome is best but I don’t have one and I’d rather stick with steel blades. I’m attempting to cut sections 1-5μ thick.
Thanks!

MarkSturtevant
Posts: 1946
Joined: Sat Nov 21, 2015 6:52 pm
Location: Michigan, U.S.A.
Contact:

Re: Resin Embedding

Post by MarkSturtevant »

Hello. It has been a zillion years since I've done any sectioning with a microtome. I don't know about the issues regarding resins (I wonder if there are forums more dedicated to microtome sectioning? This place may not have much of that). But anyway, one detail I remember is that we'd always keep steel blades cold by placing a chunk of dry ice in a funnel, and holding that over the blade with a ring stand. The CO2 vapor would spill over the blade, keeping it extremely cold. I believe this was done to harden the blade even further to prevent flexion. Sorry I can't be much help otherwise.
Mark Sturtevant
Dept. of Still Waters

Post Reply Previous topicNext topic