Question

This is for my biochemistry lab, the experiment is dealing with trypsin and BPTI. I need to make a graph: plot the absorbance change per minute versus the BPTI concentration for each cuvette.

here are my cuvettes and amount of BPTI added to each

1- 0uL BPTI added

2- 10 uL BPTI added

3-20 uL BPTI added

4-30 uL BPTI added

5- 40 uL BPTI added

6- 50 uL BPTI added.

Each cuvette has a different amount of water and trypsin added to them, for a total volume of 100 uL in each cuvette.

I was give a sample of BPTI for which I had to find the concentration. Using the absorbance, I calculated that the concentration was 0.035mM. We then had to dilute this 10-fold, so to 0.0035mM.

I am not sure how to find the concentration of BPTI in each cuvette with this information. The molecular weight of BPTI is 6500. I don't know if that is needed.

I feel like this should be really easy, but I am having trouble doing this.

Answer 1

Make a table

S.No.	BPTI (uL)	Water	Trypsin	OD
1.	0	90	10
2.	10	80	10
3.	20	70	10
4.	30	60	10
5.	40	50	10
6.	50	40	10

BPTI molecular weight = 6500

BPTI concentration = 0.035 mM

If it is 10 fold BPTI concentration= 0.0035 mM

C1V1= C2V2

0.035 X 100 = C2 X 10

C2= 0.035 X 100/10

            = 0.0035 mM

If it is 10 fold BPTI concentration= 0.00035 mM

C2= 0.035 X 100/20

            = 0.175 mM

If it is 10 fold BPTI concentration= 0.0175 mM

C2= 0.035 X 100/30

            = 0.00116 mM

If it is 10 fold BPTI concentration= 0.000116 mM

C2= 0.035 X 100/40

            = 0.875 mM

If it is 10 fold BPTI concentration= 0.0875 mM

C2= 0.035 X 100/50

            = 0.07 mM

If it is 10 fold BPTI concentration= 0.007 mM