I would like to ask you for help with the following problems. I have done an analysis of the solvent which contains knowns impurities: imp 1, imp 2, imp 3, imp 4 and unknowns . To prepare the reference solution of known impurities the same solvent as tested solution is used. That means if chromatogram obtained with the test solution (solvent) have the same retention time as the peaks due to imp 1 – imp 4, the areas of such peaks must be subtracted from the peak areas at these retention times in the chromatograms obtained with reference solution (problem 1). And problem 2 to create calibration curve for the corrected areas of the impurities.
I am using OpenLab CDS v 2.5.