PERCENTAGE OF RT WINDOW IN HPLC

[FARD]

HOW MUCH RT SHIFT IS ALLOWED IN DAY-TO-DAY ANALYSIS FOR LATE ELUTING PEAKS?

[tom jupille]

No simple answer to that. Usually 1% or so should be good enough. If you have only a few, well-separated late peaks, you could probably get away with more. In principle, the retention time reproducibility has to be good enough to maintain specificity (i.e., so that you don't misidentify peaks).

[Benjamin]

Fard,

It would be better for you to determine how much your system suffers over a period of time, and then determine how wide the RT window has to be, or can be, for the analytes to be properly named in your chromatograms.

RT shifts are dependent of many operational parametres, column age, mobile phase stability, pump performance, column deterioration, temperature, leaks, etc. Therefore it is not possible to establish an absolute number for this.

Good Luck,

Benjamin