Bradford Method Lab: Investigating Discrepancies in Protein Concentrations

[lha08]

Homework Statement

I did a lab which consisted of using the Bradford method and graphed the standard protein concentration and the absorbancies of BSA standard dilutions and used the slope in order to determine the protein concentrations of 3 unknown samples using their absorbance values. When I found the protein concentrations of the 3 unknown samples (which are milk, protein drink and soy milk) and compared their experimental values to their actual protein concentration on the nutritional label, they were significantly lower. Like for example, the experimental protein conc. for the milk i got 21576 µg/ml, while the value on the label is 36000 µg/ml...I'm having a hard time finding out why they are lower? Is it because of errors in the experiment?
I don't know if I gave enough detail of the lab so if there's anything you don't understand, please tell me.

Homework Equations

The Attempt at a Solution

 

[Nino MMP]

It is likely that the differences between your experimental results and the actual protein concentrations on the labels are due to errors in the experiment. It could be due to a number of factors, such as incorrect dilution of the samples, inaccurate measurements, or a miscalculation in the calculations for the protein concentrations. In addition, the protein concentration values on the labels may not be accurate, so it is possible that the actual protein concentrations of the samples are different than what is stated on the labels.