To duplicate the same retention times for analyzed compounds from other sources of methods, as in application notes, gradient conditions have to be adjusted according to the instrument used for parameters such as dwell volume, pump accuracy etc.

Also, each instrument has different plumbing (dimensions of the tubing), so obtaining exactly the same retention times may be virtually impossible. Therefore, using alpha values or relative retention times is a better way to determine precision and reproducibility.

This can be especially significant when attempting to duplicate application notes from our online Resource Center and website.