Chiral thin-layer chromatography

Enantiosepatation of racemic Baclofen (left). Pure (S)-enantiomer (right).[1]

Chiral thin-layer chromatography is a variant of liquid chromatography that is employed for the separation of enantiomers. It is necessary to use either

• a chiral stationary phase or
• a chiral additive in the mobile phase.

The chiral stationary phase can be prepared by mixing chirally pure reagents such as L-amino acid, or brucine, or a chiral ligand exchange reagent with silica gel slurry,[2][3] or by impregnation of the TLC plate in the solution of a chiral reagent.[4]

The principle can also be applied to chemically modify the stationary phase before making the plate via bonding of the chiral moieties of interest to the reactive groups of the layer material.[5][6]

See also

• Chiral column chromatography

References

1. Singh, Manisha; Malik, Poonam; Bhushan, Ravi (2016). "Resolution of enantiomers of (RS)-baclofen by ligand exchange thin layer chromatography". Journal of Chromatographic Science. 54 (5): 842–846. doi:10.1093/chromsci/bmw014. PMC 4890457. PMID 26896346.
2. Bhushan, Ravi; Martens, Jürgen (1997). "Direct Resolution of Enantiomers by Impregnated TLC". Biomedical Chromatography. 11 (5): 280–285. doi:10.1002/(SICI)1099-0801(199709)11:5<280::AID-BMC697>3.0.CO;2-U. PMID 9376709.
3. Sajewicz, Mieczysław; Piętka, Robert; Kowalska, Teresa (2004). "Chiral Separation of (S)-(+)- and (R)-(−)-Ibuprofen by Thin-Layer Chromatography. An Improved Analytical Procedure". Journal of Planar Chromatography: Modern TLC. 17 (2): 173–176. doi:10.1556/JPC.17.2004.3.3. S2CID 94295876.
4. Günther, Kurt; Martens, Jürgen; Schickedanz, Maren (1984). "Thin-Layer Chromatographic Enantiomeric Resolution via Ligand Exchange". Angewandte Chemie International Edition in English. 23 (7): 506. doi:10.1002/anie.198405061.
5. Ala, Alak; Armstrong, Daniel W (1986). "Thin-layer Chromatographic Separation of Optical, Geometrical, and Structural Isomers". Analytical Chemistry. 58 (3): 582–584. doi:10.1021/ac00294a020.
6. Del Bubba, Massimo; Checchini, Leonardo; Lepri, Luciano (2012). "Thin-layer chromatography enantioseparations on chiral stationary phases: a review". Analytical and Bioanalytical Chemistry. 405 (2–3): 533–554. doi:10.1007/s00216-012-6514-5. PMID 23161065. S2CID 22147187.