Lasalocid adsorbed on porous graphitic carbon as a chiral selector, in capillary liquid chromatography

Abstract Lasalocid, which has high affinity for porous graphitic carbon (PGC), has been dynamically adsorbed onto PGC and used in capillary liquid chromatography. Several enantiomers of amines, acids, amino acids and alcohols have been separated on this system and the influence of the solute structure has been studied. For example, 1-(1-naphthyl)ethylamine enantiomers showed an extraordinary separation factor ( α ≈21), whereas the enantiomers of the positional isomer 1-(2-naphthyl)ethylamine showed a more moderate separation factor ( α ≈2). Decreasing the methanol concentration enhanced the selectivity for 1-(1-naphthyl)ethanol, 1-(2-naphthyl)ethanol, 2,3-dibenzoyltartaric acid and 2,3-di- p -toluoyltartaric acid. No change in selectivity could however be found when the chiral selector concentration and ionic strength were varied. The chromatographic system has been stable and the adsorption of Lasalocid has been reproducible.