Hello everyone, I am currently trying out a gel permeation chromatography instrument. I would like to ask about testing dextran samples using a universal curve that I have created. The molecular weight (MW) values are within the expected range, but the alpha values are negative, which is not possible. (As a note, I ran the experiment with a flow rate of 0.5 and retention time of 15 minutes, and another run with a flow rate of 1 and retention time of 30 minutes). I would appreciate an explanation of whether there is something wrong with the universal curve I created. Thank you.
