An Efficient Ambient Ionization Mass Spectrometric Approach to Detection and Quantification of the Mescaline Content of Commonly Abused Cacti from the Echinopsis Genus

Unregulated cacti from the genus Echinopsis are used recreationally as mescaline-containing alternatives to the outlawed peyote. Echinopsis-derived plant materials appear in a variety of nondescript forms, making rapid assessment of whether they are mescaline-containing materials or simply innocuous plant-derived food products, very challenging. Reported here is a DART-HRMS approach for the rapid detection of mescaline in whole plant material and a validated method for the quantification of mescaline in cactus tissue, using mescaline-d₉ as the internal standard. Calibration curves exhibited R² values of ≥0.995, and the method exhibited a LLOQ and a linear range of 1 ppm and 1–100 ppm, respectively. Application of the method to commercially available Echinopsis spp. yielded results consistent with previous studies performed by GC- and LC-MS, with mescaline levels of <2% dry weight in all cases. Therefore, DART-HRMS is a suitable technique for the rapid screening of mescaline and its subsequent quantification within complex plant-derived matrices.