Page 1 of 1
retention time shift using gradient
Posted: Sun Aug 01, 2010 2:29 pm
by emanuele.scollo
I am currently experiencing RT shift when using the following gradient:
A=0.1% formic acid
B=MeOH
Time %B
0 20
9 90
11 90
12 20
14 20
the column used is a Phenomenex Kinetex C18 2.1x100 mm 2.6µ. I would be really grateful if I could get some advice on how to solve this problems.
Re: retention time shift using gradient
Posted: Sun Aug 01, 2010 5:50 pm
by jiang295
what kind of shift you are experiencing?
all of peaks shift in the same pattern,
or only early peaks shift
or some peaks shift irregularly?
I am currently experiencing RT shift when using the following gradient:
A=0.1% formic acid
B=MeOH
Time %B
0 20
9 90
11 90
12 20
14 20
the column used is a Phenomenex Kinetex C18 2.1x100 mm 2.6µ. I would be really grateful if I could get some advice on how to solve this problems.
Posted: Sun Aug 01, 2010 7:30 pm
by bisnettrj2
Try lengthening the re-equilibration time at 80%A at the end of your gradient (try 10 minutes instead of 2 minutes to start). If your RT problem is remedied, you weren't re-equilibrating long enough. If you post more details, we can give better advice.
System type?
Flow rate?
Gradient dwell volume?
And the answer to jiang's question above...
Shift retention time
Posted: Mon Aug 16, 2010 5:24 pm
by emanuele.scollo
I lengthened the equilibration time and the retention time are conistent now thanks for the help