A stock protein sample that has a concentration of 250.0mg/ml. You need to dilute this sample to 20.0 mg/ml in buffer. The final volume of the diluted solution is 5.0ml. how much of the stock protein solution and buffer are required to achieve this? Answer with appropriate sig figs.
you want 5ml of 20mg/ml in buffer.
you are diluting the solution 250/20 times, or 12.5 times. So you need one part original protein sample, 11.5 parts buffer.
What is each part? 1 part=5.0ml/12.5=4ml
11.5 parts= 46ml
To dilute the stock protein sample from 250.0 mg/ml to 20.0 mg/ml in a final volume of 5.0 ml, you can use the formula:
C1V1 = C2V2
Where:
C1 = Concentration of the stock protein solution
V1 = Volume of the stock protein solution
C2 = Desired concentration of the diluted solution
V2 = Final volume of the diluted solution
In this case, substituting the given values into the formula, we get:
(250.0 mg/ml)(V1) = (20.0 mg/ml)(5.0 ml)
Solving for V1, the volume of the stock protein solution, we have:
V1 = (20.0 mg/ml)(5.0 ml) / (250.0 mg/ml)
V1 = 100.0 ml / 250.0 mg/ml
V1 = 0.4 ml
Therefore, you will need to transfer 0.4 ml of the stock protein solution.
To determine the buffer volume required, you subtract the volume of the stock protein solution from the final volume of the diluted solution:
Buffer volume = Final volume - Volume of stock protein solution
Buffer volume = 5.0 ml - 0.4 ml
Buffer volume = 4.6 ml
Thus, you will need to transfer 0.4 ml of the stock protein solution and add 4.6 ml of buffer to achieve the desired dilution.