I was wondering if a cryopreserved tissue in sucrose/formalin could be also used for paraffin embedding, that is, going through series of alcohol after sucrose cryopreservation?
yes you can, after fixation in a suitable fixative , proceed for paraffin embedding, through the graded series of alcohol-xylene-paraffin -------------
First you need to go through different gradients of water and then alcohol and then xylene and then paraffin. I think this will be sufiecient
I am sorry to say I disagree with the other answers.
It is best to fix and then to go into wax processing without sucrose. If the tissues have been through cryopreservation with 30% sucrose the membranes tend to look wrinkled after wax processing. If you are looking at large structures then it will be ok but if you are looking at fine structures they may look strange. If this is the only tissue you have then leave it PBS at 4oC for 2 -3 days (change the PBS each day) to remove the sucrose then do the normal wax processing.
Thanks so much for your tips. I have to say that the tissue is already fixed in PFA/Glutaraldehyde. Since I intended to do cryo sectioning at the beginning, I kept them in sucrose/formalin with sodium azide for long tissue preservation. Now I need to go for paraffin processing and I think it is a good idea to get rid of the sucrose first and then process for paraffin. By the way, it is rat brain, could I possibly ask for detailed timings in series of alcohol, xylene and ... for tissue processing in paraffin?
Looking forward and all the best
I am also looking for a protocol on how to embed rat brain in paraffin. Can someone give me a protocol and how long I need to leave in each solution of alcohols and xylenes. Please help .Thank You!
here are some links to protocols for paraffin tissue processing