Chromatography Forum

Hello,

I'm looking for an HPLC-method for the separation of a racemic mixture of D,L-3-phenyllactic acid. Especially, I would be glad to receive some advise which column to chose. There are a couple of columns on the market for the separation of amino acids (using BSA or an amino acid derivative coupled to the stationary phase) but I cannot find any information if they would work for my substances. In fact, phenyllactic acid is only phenylalanine where the amino group is replaced by a hydroxyl group.
I already tried ligand exchange using L-proline and Cu(II+) as mobile phase on an RP-18 column, but it cannot work due to detection problems (Absorption of proline in the region where phenyllactic acid absorbs).

Thank you

I didn't know you could do ligand exchange such as this on a C18.. heck that could really bring down the costs of some chiral applications

We've used a Chirex 3126 phase for phenylalanine and some of its boronic acid derivatives along with some other aromatic AA's. There's more than likely a Daicel phase capable of doing the job but I can't suggest which one to start with offhand

As a side thought, if for ligand exchange we need sites available to coordinate metal ions, eg. Cu2+, would silica work?

Found a paper describing the separation of this compound and others -I've not read it fully but it may help you:

Chromatographic resolution of organic acids using the Kromasil-CHI-TBB chiral stationary phase
Chirality [0899-0042] Andersson yr:1999 vol:11 iss:5 pg:420

For Daicel columns, putting the structural features into the Chirbase column selection tool from Chiral Technologies recommends Chiralcel OD.

I suggest trying a Chirbiotic column from Astec. They are excellent columns for amino acids, and it is very likely that you will get the desired enantioseparation. I suggest starting with the chirobiotc T, or contacting them through the website, they should be able to provide some helpful suggestions.

http://www.astecusa.com/index.htm


Good luck