Simultaneous analysis of tropane alkaloids in teas and herbal teas by liquid chromatography coupled to high-resolution mass spectrometry (Orbitrap)

A new method has been developed for the simultaneous determination of 13 tropane alkaloids in tea and herbal teas using high-performance liquid chromatography coupled to an Exactive-Orbitrap analyzer. A mixture of methanol, water, and formic acid was used for the extraction of the target compounds followed by a solid-phase extraction step. The validated method provided recoveries from 75 to 128% with intra- and interday precision lower than or equal to 24% (except for apoatropine). Limits of quantification ranged from 5 to 20 mu g/kg. Eleven tea and herbal tea samples and two contaminated samples with Datura stramonium seeds were analyzed. Tropane alkaloids were detected in six samples with concentrations from 5 (apoatropine) to 4340 mu g/kg (sum of physoperuvine, pseudotropine, and tropine), whereas concentrations from 5 (apoatropine) to 1725 mu g/kg (sum of physoperuvine, pseudotropine, and tropine) were found in the contaminated samples.