Protein storage and BSA - (Feb/08/2007 )

Hi,
I recently reconstituted some growth hormone. I used a protocol from another lab stating that it should be stored in DMEM and 1% BSA...well, stupid me, I didn't realize the BSA I was using was a very low percentage and I ended up storing it at 0.08%. I recently used it in cell culture and didn't get a dose effect. This is an experiment that has not been done before so it is possible that growth hormone doesn't work in these cells...but I am racking my brain for a reason.

Could it be that the low BSA resulted in a significant loss of GH?

Even if I did loose some protein because of the lack of BSA, wouldn't I still see an effect at higher doeses (i.e., I was using 100x the dosage which I should have seen an effect)?

When you reconstituted protein do you use it immediatly or store at 4C or frozen ?