Bradford assay blank....why bother?? - (Jul/30/2012 )

Im just reading the procedure for a biorad (bradford assay) which involves the preparation of a protein blank which is subtracted from all standards and the sample?

Why bother, surely the blankis the same for all of them (unless one has made up a sample in a completely different buffer) so if one reads of the standard curve, one would get the same answer???

Am I wrong?

Confused.com

you need the blank to zero the spectrophotometer.

you need the blank to zero the spectrophotometer.

But if I plot the standards without zeroing against then read off the sample tube (again without zeroing).....I will get the same answer as if I had zero. Essentially what zeroing does is subtract the same value from exerything...ie standards, samples etc etc.

blanks for the bradford are relatively high absorbance. if you don't zero then you may be taking readings beyond the linear range of the spectrophotometer.