[Gernald]

Hello all,
I'm working on some stuff and was wondering if someone could point me in the right direction as I have a test and this is the only question I can't seem to get.

"Five microliters of a 10-to-1 dilution of a sample were added to 5ml of Bradford reagent. The absorbance at 595nm was 0.78 and, according to a standard curve, cooresponds to 0.015mg of protein on the x-axis. What is the protein concentration of the original solution?"

I was thinking about using Beers Law to calculate the concentration of the new solution given that A=ElC. But, I'm not sure of extinction coefficient. Next I would try and use C1V1=C2V2. But I'm not sure if it even wants me to use Beers Law given the standard curve statement.

Another thing I've tried is to use the mass of the protein in some odd number of ml to find the concentration of the new solution and using that to find the concentration.

In both methods I seem to get trapped about halfway through.

Any help would be AMAZING!!

Thanks!

[DrBob1]

Your data gives the amount of protein in the diluted sample. You say it's a 10:1 dilution so I guess the original aolution is 10 times the new concentration. However that would seem to be an impossibly large concentration. Work it out and see for yourself.