I was using Bradfords reagent for protein quantification in microplate reader. The problem I faced was I got variations in house keeping gene. The pity is that some sample even did not show the band mimicking there is no protein at all for the house keeping gene. So I am planning to use nanodrop 2000c for protein quantification using Bradfords reagent. Could you please suggest me the methods of preparing standards and sample using Bradfords reagent method. I have proteins from mouse brain, prepared in lysis buffer with cocktails.