From medical science work I have done on frozen skins for IF/H&E staining you do want to process them as soon as possible. You can freeze the sample and process later but once cut its was best practice to stain. I am not sure if that was a workflow process thing or not but I imagine you might see freezer burn or cellular damage a bit quicker with a 5um slice vs a whole tissue which may through off your differential. Just an educated guess though

Thanks Stephen

Hey, so asked a college and he has left section in the freezer for a few weeks/month for IF work before and they were fine.

Thanks :) Stephen Reynolds

Welcome, best of luck

Dear Paula,

we have frequently cut shock frozen (in isopentane cooled by liquid nitroge) tissue and stored the unfixed slides for later use at -80º (up to 10 days). That always worked quite well.

- I do not think that you have to fix the sections immediately if you will later use them for H&E staining.

- Fixing with ice cold acetone is bad for immunohistochemistry and even worse for H&E staining.

Best regards, Fred

Thanks for your reply Fred Sinowatz . Which fixative would you recommend then?