For years, I have used a hybrid Epon-analog resin to embed in culture dishes. I use a standard Epon formula but utilize the following components: LX-112 and DMP-30 from Ladd Research Industries DDSA and NMA from Electron Microscopy Sciences I know it seems weird, but years ago I tried all sorts things, from the “straight” formulations from each vendor to a bunch of mixtures. This one has never reacted with the plastic of the dishes. Here is how I do the actual embedding of the cell monolayers in the dishes:1)After the last 100% ethanol, remove the alcohol and cover the bottom of the well with a layer of resin mixture that is about 2 mm deep.2)Insert embedding tubes that are made by cutting the pyramidal bottoms off of BEEM capsules (just slice them with a fresh razor blade and be sure to insert them so that the manufactured end rather than the cut one is sitting against the dish).3)After inserting labels into the tubes, put them into the oven at 60° overnight.4)In the morning, fill just the embedding tubes and return everything to the oven again to finish polymerizing.5)When the resin is cured, grab the tubes with a pair of needlenosed pliers and snap them out. Sometimes a bit of the bottom of the dish comes away with the block, but often a very smooth block face results. If some of the dish comes up, it is easy to see under a dissecting microscope, and the dish portion comes away easily when trimming the block face.I often cut away part of the block face with a jeweler's saw, either to keep it in reserve or to re-embed it in order to get cross sections, and then trim the rest into a narrow rectangle.
Simplified in situ preparation of cultured cell monolayers for electron microscopy.
