Question

You have 5 ml of 3 mg/ml protein soluti on. (This solution is valuable so you don’t want to waste it.) How w ould you make up at least 100 μ l of 0.1 mg/ml using a convenient dilution ( i.e . how much buffer and how much protein solution do you need to add, and is it possible to pipet the amount you need accurately )? Please explain and provide the correct answer.

Answer 1

Solution :-

Initial concentration is 3 mg/ml

Final concentration needed = 0.1 mg/ml

Volume of solution needed = 100 ul

M1V1 = M2V2

V1 = M2V2/M1

     = 0.1 mg/ ml * 100 ul / 3 mg/ml

    = 3.33 ul

So

We need to use 3.33 ul of the original stock solution of the protein and 100 – 3.33 = 96.67 ul of the buffer solution and mix them

By the concvensional dilution method we cannot accurately pipette out 3.33 ul solution. So it is difficult ot make such solution with convensional methods.