HILIC Columns and analysis of lipids

[Valerie BB]

Hello Everybody,

We work about analysis of milk lipids (which are composed mainly of neutral lipids but which contain also polar ones) and we use normal phase liquid chromatography (with a silica column) to analyze them. I read some papers about HILIC columns and I wonder if it would be interesting for us tu use this type of column. Unfortunately, I didn't find a lot of informations about HILIC column for the analysis of complex lipids. Do you have experience in this domain do you know some publications who could help us to make our choice? Thank you for your answers.

[Gerhard Kratz]

Dear Valerie,

If you are running ONLY normal phase conditions on your HPLC instrument be careful when you switch to HILIC conditions with the sealings.
Mainly you will find 3 types of HILIC columns a) without b) with endcapping and c) with ion exchange and HILIC as mixed mode and a zwitter ion phase. Which phase will do the job is difficult to say. Please ask the manufacturers to give you a trial column.
Please do a good sample preparation. You need to get rid of the fat in the milk.
Good luck.

[Valerie BB]

Dear Gerhard,
thank you for your answer and your advices (I will take care about seals for instance). Probably, my message wasn't clear because I want to analyze lipids with HILIC column so I don't want to get rid of them!

[Andy Alpert]

You're not going to have much luck with neutral lipids in HILIC. There are a number of applications in the literature and in the application files of various companies showing its successful use for lipids with some polar groups. Examples: phospholipids (PC, PE, PS, etc.). Exactly which polar lipids are you interested in? Also, detection is going to be troublesome unless you have a mass spec or ELSD.

[Valerie BB]

Thank you Andy for your answer. As you wrote, I try to find some informations in litterature and I asked questions to suppliers but informations about use of HILIC column is very poor for the moment. If you know some labs which work with this type of column for analyzing lipids, I would be interested in being in touch with them.

[Andy Alpert]

If you supply an e-mail address, I'll send you a chromatogram off-list as an example.