Assessment 2 Task 2 – Protein Assay Calculations.
If you were on campus and participated in the practical class, you would have performed a protein
assay on the samples you extracted. You now need to report these assay results.
Analysing data.
BCA assay: Using the output from the plate reader (in Excel file), you need to plot a standard graph
of Absorbance (Y-axis) vs BSA concentration (X-axis). You then need to fit a trendline (or line-of-best fit) to the standard graph and get an equation for the trendline. By rearranging this equation, you
can calculate the protein concentrations in your extracted sample, taking into account any dilutions.
You will also need to find the R2 value of the line to show how good the standard curve is and
whether you can pipette dilutions properly.
What to put in report.
1) A BRIEF introductory paragraph. You extracted protein from coli and need to measure the
total protein concentration. You did an assay to measure the concentration and amount
of protein extracted.
2) BCA assay results. These should include:
a. A correctly labelled standard graph of Absorbance Vs Concentration that includes a
trendline, the equation of the trendline and the R2 value for the trendline.
b. A table showing the protein concentration of the samples as determined from the
graph and the protein concentration corrected by any dilution factor.
c. The volume of your sample that contains:
1D SDS-PAGE: 100ug
Shotgun LC/MS/MS: 15ug
d. The label (number) of the competency sample provided to you and the protein
concentration of the sample (determined by you from the BCA assay).
3) A conclusion.
What was the concentration determined by the assay
Submission.
Your report can be submitted as a Word Doc in Canvas.
