Metabolomics Society Forum

Hardware => Chromatography => Topic started by: DeborahMaus on January 08, 2019, 04:16:17 AM

Title: Buffering both Eluents - Acetonitrile with Ammonium Carbonate
Post by: DeborahMaus on January 08, 2019, 04:16:17 AM
Good morning fellow Metabolomicians!

We observe a Retention Time drift but a minor one. And now, while I am in the middle of optimizing, I am thinking:

Would it be better to change the apolar eluent from pure AcN to AcN with 5% water containing 10mM Ammonium Carbonate?

Thanks in advance for your effort to help to newbee! :)

Greetings from Germany!
Debbie

P.S.: HILIC mode! Polar eluent: 10mM Ammonium Carbonate in water.
Title: Re: Buffering both Eluents - Acetonitrile with Ammonium Carbonate
Post by: CoreyG on January 09, 2019, 11:32:27 PM
Hi Debbie,

I'm not a user of HILIC columns, but I've heard a few times that retention time reproducibility can be quite sensitive to pH changes. So adding a buffer to the apolar solvent could help.

There are a few discussions going on in the forum about correcting for retention time drift. So if you can't sort it out, it is possible to correct some of the issues with software (such as XCMS).

Keep us informed of your trials - there are a lot of others that will benefit from your experiences!

Cheers,
Corey