If your "low salt" sample has 1.9 mg/ml protein, how many microliters (υl) would you need in order to have exactly 30 micrograms of protein? [hint: first express everything in micrograms and microliters)

(give you answer to the nearest 0.1 ul)

1 answer

To find out how many microliters (µl) of the sample you need to obtain exactly 30 micrograms (µg) of protein, you can use the following formula:

\[ \text{Concentration} = \frac{\text{Amount of substance}}{\text{Volume}} \]

Given:

  • Concentration of protein = 1.9 mg/ml
  • Desired amount of protein = 30 µg

First, convert the concentration from mg/ml to µg/µl:

\[ 1.9 , \text{mg/ml} = 1.9 , \text{µg/µl} \text{ (since 1 mg = 1000 µg and 1 ml = 1000 µl)} \]

Now, we set up the equation to find the volume (V) needed:

\[ 30 , \text{µg} = 1.9 , \text{µg/µl} \times V , \text{(µl)} \]

Now solve for \(V\):

\[ V = \frac{30 , \text{µg}}{1.9 , \text{µg/µl}} \approx 15.7895 , \text{µl} \]

Rounding to the nearest 0.1 µl:

\[ V \approx 15.8 , \text{µl} \]

Thus, you would need approximately 15.8 µl of the "low salt" sample to obtain exactly 30 micrograms of protein.