How to make mES cells attch to differentiate? - (Dec/27/2006 )

Hi, there, Recently, I met a problem, I wanted to make mES cells to attach to differentiate, although I have tried to coat the dish with IV callagen, and induced cells in serum free medium supplemented with growth factors, these cells didn't attach unless addition of 0.2 to 0.5 % FBS, however, since the composition of serum is complicated and may affect inducing effect of added growth factor.I want to remove FBS and add someting to promote cell attachment while don't affect cell differentiation. Could anybody have experience in this experiment.What shoul I add to the medium to promote attachment.Thank you!

What concentration of Collagen IV are using for the assays? I use 25ug/ml with no problems, cells attach very good. FBS is very important, I think it doesn't affect the assays if the differentiation factors are in medium. I use alfa-MEM media for differentiation, works fine.