A rapid and simple method for the determination of psychoactive alkaloids by CE-UV. Application to Peganum harmala seeds infusions

FERNANDO BENAVENTE; MARCOS TASCON; LEONARDO G. GAGLIARDI; NORA VIZIOLI

DRUG TESTING AND ANALYSIS

John Wiley and Sons

Año: 2016

1942-7603

The β-carboline alkaloids of the harmala (HAlks) group are found at high levels in some plants, like in Banisteriopsis caapi, which is one of the ingredients of the South American psychotropic beverage Ayahuasca. Furthermore, they occur at lower concentration in many foodstuffs, certain human body fluids and tissues. Separation of HAlks is a great analytical challenge because of their structural similarities (a 9H-pyrido[3,4-b] indole ring with slight differences in substituents, acid-base properties or insaturations). In this work, we report the complete baseline separation in less than 10 minutes of a mixture of six HAlks (i.e. harmine, harmaline, harmol, harmalol, harmane and norharmane) by capillary electrophoresis with ultraviolet detection (CE-UV). Optimum separation in fused silica capillaries was achieved using a background electrolyte (BGE) of 50 mM Tris-HCl (pH 7.8) with 20% (v/v) of methanol. The separation method was validated and inter-instrumental method transfer was evaluated for three different commercial instruments. The method was applied to a tea prepared from the psychoactive seeds of Peganum harmala (Syrian rue), which is used to prepare ?Ayahuasca analog? teas, and to ethanolic extracts of the Atlantic edible seaweed Undaria pinnatifida (wakame), which is worldwide used as a foodstuff and in traditional oriental medicine. Harmaline, harmine and harmol were present in tea samples at concentrations of 53 (±2), 24.3 (±0.4) and 16.4 (±0.7) μg/L, but LODs were not enough to detect HAlks in wakame extracts. However, the potential of the extraction and separation method was proved with spiked algae samples.