Chromatography Forum

I have searched and found many methods for Imidizole many employ a C18 column. I am trying to seperate Imidazole and 2Methyl-Imidazole. The C18 column can not do this. I have had some sucess with a CN column however due to poor column reproduceabilty (excipient interfernce from column batch to batch) I am trying to avoid these. Can anyone suggest an alternative. I am currently truing an NH2 Buff/ACN column with no sucess....help?

This is an ideal separation for HILIC - hydrophilic interaction chromatography. Use a silica column designed for HILIC, and buffer-MeCN, with a high concentration of MeCN. The amino column is the wrong choice due to ionic repulsion of the imidazole.

thanks uwe....are all column manufactures equal? I'll give it a shot

I'll take this one...

All column manufacturers are created equal, but some manufacturers are more equal than others.

Being employed at Waters, I recommend the Atlantis HILIC column for this application. During the development of the Atlantis HILIC column, we have evaluated and compared several silicas before deciding on the one that is used for this column.

PS: Thanks for giving me the opportunity to do a small commercial!

I would recommend using our Unison UK-Silica column. You can
run it under aqueous normal phase conditions - similar to the chromatogram below:

http://www.silvertonesciences.com/files/TI178E.pdf

Hi Bgiles

C18 can separate imidazole and 2-methyl imidazole. You may need to use ion-pair reagents. Are you interested in only these two peaks or there are more you want to quantify in the same run?

you can achive seperation using following option with reverse phase system.
1. Use 0.01 molar octane sulfonic acid and play with pH between 3 to 5.
2.use Methanol as organic modifier , if that increase your runtime then you can use phenyl column that is more polar then C18 column.