soft agar assay - problems with soft agar (Apr/02/2005 )

Hi ,
i am setting up soft agar assays to look if my compound of interest blocks the transformation of particular immortalized cell line in presences of a carcinogen.
i made up the base agar layer and when i added the 0.4% top agar layer with cells , i saw that there are lumps of soft agar in my plates next day.
is it because the pre mature setting of agar before plating or something else.
any help wud be highly appreciated.

It is most likely that the agar had started to set before plating.....to avoid this you could allow the the bottle of hot agar to cool in a waterbath before you use it. I think we used a waterbath at either 40 or 45 C....has to be warm enough to stop the agar setting but cool enough not to kill your cells when you add them!