LC-MS Quantitative Determination of Atropine and Scopolamine in the Floral Nectar of Datura Species

The present study aimed at determining selected alkaloid components in the nectar of Datura species, to elucidate whether the alkaloid content of the floral nectar can lead to intoxication. A simple and rapid liquid chromatography coupled with electrospray mass spectrometry analysis was developed for the quantitative determination of atropine and scopolamine, the main toxic alkaloids of the Datura species. This method allowed the direct coupling of an electrospray mass selective detector to the LC system. Under these conditions, atropine and scopolamine were well separated from other components and detected with mass spectrometry (mass selective detector). Simultaneous determination of atropine and scopolamine was performed with gradient elution on an Ascentis Express C₁₈ (Supelco) reversed-phase column based on a new fused core particle design. Liquid chromatography coupled with electrospray mass spectrometry was used in positive ion mode. Atropine and scopolamine produced protonated species at m/z 290 and 304 (which are also the base peaks). Our data confirmed that the alkaloid characteristics for the vegetative and reproductive parts of the Datura plants may also occur in the nectar secreted by the flowers. In Datura species with large flowers and high nectar amounts, the alkaloid content increases proportionately and thus the nectar may be a potential source of intoxication.