bromophenol blue - bromophenol blue....Yellow low pH (Mar/09/2006 )

Dear Friends,
i come across a intersting phenomenon.
what i have done is I put a RT-PCR with DMSO concentraion 0 to 20%.
after RT AND DNA pcr i loaded these samples with bromophenol on 1% agrose gel. from 5 to 20% DMSO samples , on addition of samples to bromophenol blue bromophenol blue turn deep yellow.
it is well documented that at pH 3.0 bromophenol blue is yellow. but DMSO is a lewis acid then how can it turns bromophenol blue to yellow .
if anybody has came across such situation please do reply.

I don't really have answer, but in my experience i never see this situation when i use DMSO in my PCR , i don't think so it's DMSO the problem in you're situation, in my mind there would probably have an other factor which modified the PH of your mixture.

Hope it would help you a little....

thing is that just add DMSO to bromophenol blue you will get yellow color fluid like serum
take care