How long do growth factors last in complete media? - (Feb/17/2012 )

If you add growth factors to your tissue culture media (bFGF, IGF, HGF...) how long is that bottle of complete media typically still "good"? Does it vary wildly depending on the specific growth factor? I've been using recombinant human bFGF most recently. I noticed they didn't mention anything specifically in the product information or on the company web sites.

Thanks.

Note, I didn't mean to ask how often do you change it (feed them). I meant to ask how long is that bottle of media good with normal usage (sitting at 4deg C most of the time and then warmed up to 37 every time you use it). Do the growth factors denature, degrade or somehow otherwise go bad?

I used to change media with some neurotrophic factors,twice a week. So I guess they should be stable for 3-4 days.

Well I can only say that I'm using my medium, which also contains human bFGF, for about a week.

I've kept various growth factors for up to a week in media previously - but the only reason for stopping there was the duration of the experiment. It wasn't a concern I'd considered before and my gut says that if you're keeping it in the fridge it shouldn't matter at all.

Incidentally I've performed two different duplicate experiments where one set of media was kept in the cold and one in the incubator (alongside the incubation flask) and I'm analysing the results of that in the coming weeks. If it's good for a week at 37'C it would be fine for a long time in the cold.