Cryosections

Equilibrate fixed and washed embryos in sucrose (30% sucrose in 0.1M potassium phosphate buffer pH7.4) O/N 4C

Mounting
Cut section of embryo for sectioning with sharp blade
Transfer wanted section to molds with cold OCT on ice
Let tissue sink in OCT ~1h on ice
Place some crushed dry ice in tray and put OCT block in tray
Orient embryo such that anterior is towards bottom of block and embryo is standing upright
Transfer OCT block carefully to flat surface of dry ice
Keep blocks at -80C until ready to section

Sectioning
Equilibrate blocks in cryostat to -17C - -18C for at least 30min
Section 10um sections
Store slides at -80C