Embryo culture medium

Reagent	Final concentration	Amount
DMEM/F12 (+HEPES, no phenol red)	42%	15 mL
Heat-inactivated FBS	14%	5 mL
Heat-inactivated rat serum	42%	15 mL
Penicillin/streptomycin 100×	1×	360 μL
ITS-X 100×	1×	360 μL
GlutaMAX 100×	1×	360 μL
APE 2000×	1×	18 μL
CB-DMB 10 mMa	2.5 μM	9 μL
Total	–	∼36 mL

Store at +4°C for up to 1 week.

^aOnly for heart imaging at E7-E8.