Chromatography Forum

Posted: **Tue Oct 14, 2014 8:36 pm**

Hello,

I am using the Waters H-class UPLC with an ELS detector and the acquity c18 beh column. Based on my current gradient, the sample I want to analyze is eluting at a retention time of 0.4 minutes. Could someone please guide me on how to try and alter my gradient such that I can get my sample to elute at a later retention time?
The current gradient I am using is
Time(mins)/ Flow rate(mL/min)/ aqueous%/ organic%
0/ 0.32/ 60/ 40
3.33/ 0.32/ 70/ 30
6.66/ 0.32/ 80/ 20
10/ 0.32/ 90/ 10
12/ 0.32/ 60/ 40

Thanks!

Posted: **Tue Oct 14, 2014 10:20 pm**

Did you write that correctly? Are you actually *decreasing* the organic during the gradient??

Posted: **Wed Oct 15, 2014 10:08 am**

I would try a HILIC column, and if that will not give good retention time an IEX separation. Good luck.

Posted: **Tue Oct 21, 2014 9:20 pm**

What is the nature of your analyte? Neutral, acidic,basic or zwitter-ionic?

Chromatography Forum

Altering gradient to elute sample at a later retention time

Altering gradient to elute sample at a later retention time

Re: Altering gradient to elute sample at a later retention t

Re: Altering gradient to elute sample at a later retention t

Re: Altering gradient to elute sample at a later retention t