Liquid chromatographic determination of carnitine by precolumn derivatization with pyrene-1-carbonyl cyanide

A method is described for the determination of carnitine chloride in pharmaceutical preparations by precolumn derivatization and high-performance liquid chromatography (HPLC). Carnitine chloride is derivatized by reaction with pyrene-1-carbonyl cyanide (PCC) in dimethyl sulphoxide. The PCC derivative of carnitine is then used for quantitative HPLC analysis on a cation-exchange column with fluorescence detection. The calibration graph was linear over a sample concentration range from 2.0 to 20 micrograms/ml; the limit of detection was 0.5 microgram/ml under the conditions studied. The proposed method was applied satisfactorily to the determination of carnitine chloride in pharmaceutical preparations.