6. What column should I use for my application?
Polysaccharide-derived CSPs show chiral recognition abilities in organic and aqueous mixtures in LC, as well as under supercritical fluid (SFC) conditions. Their enantioselectivity, retention and resolution degree is differently modulated in those modes, due to the fact that solvent eluting strength, solvation, polymer swelling/shrinking, interaction forces (hydrogen bonding, π- π interaction, …), etc. will not be equivalent in all of them. Therefore, the choice of the mode will be an essential element in the experimental design.
The standard screening protocols adopted by companies and research groups worldwide usually use three or four analytical columns in the primary screening. Two main options for setting up the primary screening include three to four immobilised phases of newest generation (CHIRALPAK IA, IB, IC and IG) or alternatively the four traditional coated columns (CHIRALPAK AD and AS, CHIRALCEL OD and OJ). Such configurations with polysaccharide derived columns, tested on a randomly composed sample pool, and with four solvent mixtures, routinely afford complete enantiomer resolution for over 90% of the racemates examined and enantiorecognition above 95%.
Those columns constitute the primary screening kits, but a full range of other columns are also available to extend the application domain and undertake the resolution of more complex sample mixtures, other than racemates (isomeric mixtures, impurities, etc).
Three main areas for method development can be considered. To view guidelines on method development strategies, click here.
- Use of organic solvent mixtures in HPLC
- Use of water compatible mixtures in HPLC
- SFC conditions
Chiral Technologies has introduced the Column Selection Service. For primary screening, our experienced technical team will test your material on our Chiral Stationary Phases. Compounds with more than one chiral center are expected to require significantly more effort, and therefore a more extensive screening and optimization regimen will be employed.
If you would like technical assistance in performing a literature search for your application, please contact us, depending on your region: Chiral Technologies Europe (CTE), firstname.lastname@example.org, Chiral Technologies, Inc. (CTI), email@example.com,or Daicel Chiral Technologies India (DCTI), firstname.lastname@example.org
Please provide structures of the compounds you wish to separate. You can also send names of well-known compounds with similar structural features or specific derivatives of these compounds so that a structure-based search can be performed. In many cases, a separation of your compound using one or more Daicel chiral columns, or one closely related to it, will already have been reported in the literature. Based upon this search, we can usually recommend the column most likely to separate your compound.
More specific guidelines can be found in the DAICEL Application Search for Chiral Column Selection. It lists over 1,100 separations for non-proprietary racemic compounds that have been successfully resolved. These guidelines are based on empirical observations and may not correctly predict the separation of your compound.