We coat the plate in poly-D-lysine (50 ug/mL) followed by fibronectin (50 ug/mL) before plating the cardiomyocytes.

After isolating and plating cardiomyocytes from 2-4 day old pups, we fed the cells with the below full media recipe: DMEM (10% FBS, 1X P/S, 2 mM glutamine, 10 mM HEPES)

- by the way, we tried both heat-inactivated (HI) FBS and non-HI FBS and there seems to be no difference

Overall, results obtained have been inconsistent among our five total experiments (only one experiment showed strong/observable beats) and other experiments have been moderately weak (too weak to observe).