For routine paraffin processing and most stains, neutral buffered 10% formalin is a good choice. In general, mouse tissues should be fixed in formalin for 24 to 48 hours, but can be left much longer. ...

Specimen Type: Brain Tissue (gray matter only). Preferred Container: 10% buffered formalin. Other Accepted Forms: Unstained Slides. Cassettes. Paraffin Embedded (P&E) Blocks. Specimen Preparation: ...

Neither alcohol nor formalin retains specimens' true textures, and both preservatives allow specimens to move around in their containers, which can lead to breakages.