A Novel Derivatization Procedure and Chiral Gas Chromatographic Method for Enantiomeric Purity Screening of L-Carnitine

Abstract

L-Carnitine is used extensively in functional foods and food supplements; consequently, the control of its enantiomeric purity is of paramount importance. A new derivatization procedure and chiral gas chromatographic method with flame ionization detection, using a cyclodextrin based stationary phase, enables prompt, simple, and inexpensive screening of the enantiomeric ratio of L- and D-carnitine in samples with different matrices. Conversion of carnitine to β-acetoxy-γ-butyrolactone was optimized for maximum conversion and minimum racemization and time consumption. As it is shown in this study, the combination of fast gas chromatographic method with the new derivatization procedure enables an effective enantiomeric purity screening of L-carnitine in real samples such as food supplements and L-carnitine raw ingredient.