Question

You are provided with a 0.1 mM solution of proflavine (MW: 209.25 g/mol), a 6 mM solution of DNA, and solid NaCl (MW: 58.44 g/mol). How many μL of the proflavine solution would you need to make a 25 mL of the following stock solution: 1 µM proflavine, 100 mM NaCl, and 60 µM DNA?

Answer 1

Ans. Given, original stock [proflavin] = 0.1 mM = 100.0 uM

            Desired diluted stock [proflavin] in 25.0 mL final solution = 1.0 uM

            Final volume of the desired solution (diluted stock solution) = 25.0 mL

Now,

            Using C1V1 (Original stock solution) = C2V2 (diluted stock solution)

            Or, 100.0 uM x V1 = 1.0 uM x 25.0 mL

            Or, V1 = (1.0 uM x 25.0 mL) / 100.0 uM

            Hence, V1 = 0.25 mL

Therefore, required volume of 0.1 mM original stock proflavin solution to make 25.0 mL of diluted stock solution = 0.250 mL