Chromatography Forum

We are using Openlab Chemstation Ver.C for our HPLC analysis.

I am working a method which requires the use of multi-level calibration curve for quantitation of samples.

Standard solutions are prepared by diluting stock standard solution to 0.1%, 0.5%, 1.0, 2.0%, 10.0%, 50%,70%, 100%, 120% and 150% of the working concentration. These solution are divided into two groups.

The low concentration standard solutions 0.1%, 0.5%, 1.0, 2.0%, and 10.0% are only used to calculate correlation coefficient and other SST parameters but not used for quantitation of samples.

The high concentration standard solutions 50%,70%, 100%, 120% and 150% are used to calculate correlation coefficient and quantitate samples.

Currently, I have to create one calibration curve to calculate correlation coefficient for low concentration standard solutions, then delete the that calibration table and create a new one for the high concentration standard solutions.

I am just wondering is there any way to create a calibration table that has all 9 concentrations but only use 5 of them for quantitation?

If you have DAD or MWD, couldn't you collect data at two wavelengths, like 280 nm and 281 nm, use one wavelength for low range and other for high range, and have a separate calibration table for each? Maybe 1 nm is too close for the software, don't know.

Or have a second method with the second calibration table, all other conditions the same, and reprocess using that?