Improved separation of six harmane alkaloids by high-performance capillary electrophoresis

The beta-carboline alkaloids of the harmane group (harmine, harmol, harmaline and harmol) are found at high levels in some plants and occur in many natural foodstuffs and beverages. Both harmane and norharman also occur naturally in mammalian neural tissues. The harmane alkaloids are often difficult to fully fractionate using conventional high-performance liquid chromatography. We report here the successful separation of a mixture of six harmane alkaloids (harmane, norharman, harmine, harmaline, harmol and harmalol) to baseline resolution using micellar electrokinetic chromatography. The alkaloids were detected by UV absorption using diode-array spectrophotometry, which allowed characterization of individual peaks. The fractionation was rapid and was highly reproducible, with complete resolution of all six compounds within 14 min. Harmalol could also be detected directly using laser-induced fluorescence.