Question

1)You are given a protein solution with a concentration of 0.15 mg/ml. We need 10 µg for an experiment. What volume of the protein solution do we need?

My answer: Convert 0.15 mg/ml to μg/ μl and you will get 150 μg/ μl. C = M/V rearrange for Volume V= M/C , V= (10 μg)/(150 μg/ μl) = 0.06667 μg/ μl

2) Suppose we want to prepare a solution containing 100 µg of the protein at a concentration of 1 mg/ml. To do this we will first dry down enough protein solution to get 100 µg. How much do we need to dry down? How much H2O do we add to the dried protein to get the desired concentration?

My answer: You will convert 0.15 mg/ml to μg/μl and you will get 150 μg/μl, then take 100 μg and divide by 150 μg/ μl to get 0.667 μg/ μl (I don't think I am doing this right) Please help!!

3) If the protein has a M.W. = 22,000, express its initial concentration in moles/liter, in µmoles/ml and in µmoles/µl. If we want 20 µmoles for a reaction, what volume do we need?

4) Suppose we want 1 ml of a 10 µg/ml solution. How much H2O and protein stock must we add to get this?

5) Suppose we want 100 µl of a 0.1 µg/µl solution. How much H2O and protein stock must we add to get this?

I am trying to do these questions but I am horrible at this and I feel like I am doing it wrong. I need help please!!

Answer 1