calculating yield

[damianomigani]

hi all,

i'm running a capture anion exchange step on an akta on filtered harvest producing an enzyme.
i just want to double check my logic in calculating the yield is correct:

I feed in the column 7.5ml of harvest containing 0.06mg/ml of product = 0.45mg (product NOT total protein)
I collect 2ml fractions throughout the whole chromatogram.
my eluate peak comes out as 6 fractions (12ml) and the concentration in each fraction varies between 0.01 to 0.04 mg/ml. I averaged out the concentrations to 0.025mg/ml, therefore 12 *0.025 = 0.3mg
my yield is therefore 0.3/0.45 x 100 = 67% and i lose 33%.
question 1) is this the yield or the protein recovery?
question 2) shouldn't i see a more concentrated product in the eluate?
question 3) does this make sense to you?

thank you for your help

[Peter Apps]

Depending on the shape of the peak, averaging 0.01 and 0.04 probably does not give you the average concentration over your eluate peak. Calculate the mass of product in each fraction, then sum the masses.

Peter