Direct chromatographic resolution of carnitine and O-acylcarnitine enantiomers on a teicoplanin-bonded chiral stationary phase

R-(-)-Carnitine (vitamin B-T) plays an important role in human energy metab olism, by facilitating the transport of long-chained fatty acids across the mitochondrial membranes. Its (S)-enantiomer acts as a competitive inhibito r of carnitine acetyltransferase, causing depletion of the body R-(-)-carni tine stock. Consequently, the separation of carnitine enantiomers is very i mportant both to study their biological activities and to control the enant iomeric purity of pharmaceutical formulations. In the present paper we desc ribe an easy, fast and convenient procedure for the separation of the enant iomers of carnitine and O-acylcarnitines by enantioselective HPLC on a labo ratory-made chiral column containing covalently bonded teicoplanin as selec tor. High enantioselectivity factors (alpha values ranging from 1.31 to 3.0 2) and short-time analyses characterize the analytical procedure; in additi on, analytes are easily detected by evaporative light scattering with no ne ed for preliminary derivatization. The effects of pH and ionic strength of the mobile phase and of the nature of the organic modifier on the enantiose lective separations were also investigated. (C) 1999 Elsevier Science B.V. All rights reserved.