Hi all,

I am looking for advice on what could be going wrong with my zebrafish caudal fin tissue fixation that would cause the sample to fall out of the embedding while cryosectioning. During cryo as we get closer to the sample itself, the embedding starts to become flaky, and we have even had the fish tail fall completely out of the embedding.

The protocol tried so far includes 24 hours in 4% PFA and 7 days in EDTA + sucrose before embedding in 4% agarose and submerging it in 30% sucrose until it sinks to the bottom. Thank you!