I am preparing a methanol stock of fixed embryos at different developmental stages (up to 5dpf) and storing them at -20C until further use. I fix embryos in 4% PFA in DEPC-PBS at 4C over night, then wash them twice in DEPC-PBT and perform methanol series (25%-absolute). In the end I rinse the embryos in absolute methanol again and store them in 2ml epi at -20C.
Can I use the embryos that received this treatment also for qPCR? I am worried about RNA quality after fixation and dehydration.
The situation is, that I'm getting a large batch of embryos and I need to fix them at certain developmental stages, but this is not possible in my own lab, so I'll be unable to extract RNA straight after euthanasia.
Does anyone have any suggestions?
Thank you!