decreasing in retention time Vs. column deterioration

[fish.vegt]

Dear All
I am writing a investigation regarding to the continue sequential runs drop in retention time each time from one to the next, and I am wondering is there any deviance says there is any relationship between the retention time decrease vs. column deterioration?

Thank you,

[HPLC chemist]

As I recall the answer is no! However, there may be a requirement in the validation documentation for a RT window. If not you can always add an addendum to the AMV protocol.

[mattmullaney]

Hi, fish.vegt,

I agree with HPLC Chemist in part--the method aught to include a range of acceptable retention times per peak (or relative retention times).

Is it possible that column stationary phase deterioration may cause a reduction in retention time for peaks--yes. Is this the only cause of this particular phenomenon--no.

Feel free to refer here

http://ccc.chem.pitt.edu/wipf/Web/LCMS% ... ooting.pdf

(pgs. 5-6), and

http://www.chromatographyonline.com/ret ... case-study

[fish.vegt]

Thank you for the comment and the valuable reference