Protocol for the electroporation of ES cells. Cells are routinely passaged two days prior to electroporating. Usually one 10 cm plate at approximately 80% confluency will provide enough cells for 1-2 electroporations. - [Read Electroporation of ES Cells Protocol]
This protocol describes passage of ES cells. They should be split at 1:3 to 1:7 every 2-3 days depending on their growth rate when they reach 70% confluency. They should never be allowed to grow past 90% confluency, but rather they should form tightly packed colonies not touching each other. - [Read Passage of Embryonic Stem (ES) Cells Protocol]