How to find the concentration of nucleic acid solution using optical density?

zoeey

I just did this lab where I measured the absorbance of nucleic acid solutions and I have to find the concentration (in mg/mL) of each nucleic acid at different temperatures at 260nm. It is given that they have an absorption maximum at 260nm with an intensity of 17 OD (optical density) units/mg. We are expected to use this value to find the concentrations. I do not know how to go about this with the calculations.

Here is how I think it should be calculated

Assuming the measured absorbance was 0.278 and the total volume was 3.05mL

0.127*1mg/17=7.47*10^-3mg
7.47*10^-3mg/3.05mL=2.44*10^-3 mg/mL

Are my calculations right?

Thank you!