the Pierce BCA Kit comes already with Albumin Standard Ampules, 2 mg/ml, diluted in a solution of 0.9% saline and 0.05% sodium azide that are used for the Preparation of Diluted Albumin Standards.
As you know, the standard should be diluted in the same buffer as the sample. Letīs say the sample is diluted in RPMI or any other medium - you are advised to use the same medium for your diluted albumin standards.
My problem is: When you do a series of a 1:2 dilution, there will be always 50% salt solution and 50 % medium for every standard except the 2mg/ml beginning standard that has 100 % salt solution (ok, for the lower standards the salt solution will be diluted out but something is still there). On the one hand, there will be less background signal measured (assumed that there is one) compared to the samples that are in 100% medium. On the other hand, you have to subtract the blank (medium) from your standards that is nonsense for your highest standard (2 mg/ml) because it isnīt diluted in medium.
Hope you get my point!
Edited by Nose, 11 June 2010 - 02:01 PM.