During lab, you are provided with a stock antibody solution (Ab) that has a concentration of 400 μg/μl. For lab, it is necessary make the following dilutions (Fill in the blanks):
5μL of Stock Ab + 195μL of buffer to make a 1:____ dilution at _______μg/μL
20μL of 1:100 stock + 60μL of buffer to make a 1:____dilution at ______μg/μL
5μL of Stock Ab + 195μL of buffer to make a 1:4 dilution at 100 μg/μL
20μL of 1:100 stock + 60μL of buffer to make a 1:500 dilution at 16 μg/μL
To determine the necessary dilutions, we need to understand the concept of dilution factor. The dilution factor is the ratio of the final volume to the initial volume. It represents how much the solution is diluted.
For the first dilution:
1. We are adding 5 μL of Stock Ab to 195 μL of buffer.
2. The total volume of the solution after dilution is 5 μL + 195 μL = 200 μL.
To calculate the dilution factor, we divide the total volume by the initial volume:
Dilution factor = Total volume / Initial volume
Dilution factor = 200 μL / 5 μL
The dilution factor for the first dilution is 40.
Next, let's calculate the concentration after dilution:
The initial concentration of the Stock Ab is 400 μg/μL.
To calculate the concentration after dilution, we multiply the initial concentration by the inverse of the dilution factor:
Concentration after dilution = Initial concentration / Dilution factor
Concentration after dilution = 400 μg/μL / 40
The final concentration after the first dilution is 10 μg/μL.
Therefore, the necessary dilution for the first dilution is 1:40, and the final concentration is 10 μg/μL.
For the second dilution:
1. We are adding 20 μL of 1:100 stock to 60 μL of buffer.
2. The total volume of the solution after dilution is 20 μL + 60 μL = 80 μL.
To calculate the dilution factor, we divide the total volume by the initial volume:
Dilution factor = Total volume / Initial volume
Dilution factor = 80 μL / 20 μL
The dilution factor for the second dilution is 4.
Next, let's calculate the concentration after dilution:
The initial concentration after the first dilution is 10 μg/μL.
To calculate the concentration after the second dilution, we multiply the initial concentration by the inverse of the dilution factor:
Concentration after dilution = Initial concentration / Dilution factor
Concentration after dilution = 10 μg/μL / 4
The final concentration after the second dilution is 2.5 μg/μL.
Therefore, the necessary dilution for the second dilution is 1:4, and the final concentration is 2.5 μg/μL.