This paper presents the process for establishing a validated quantification method for psychoactive compounds within complex plant matrices through its application to the detection and quantification of atropine in Datura stramonium seeds.
The utility of direct analysis in real time-high resolution mass spectrometry (DART-HRMS) for quantification of a variety of compounds has been explored, but the number of reports of validated methods using this technique is limited. Furthermore, despite the increasing use in crime labs of DART-HRMS for the detection and identification of drugs of abuse, very few published reports have appeared describing how the method can be exploited for the analysis of small molecules of interest within complex matrices such as plant tissues. In this paper, the authors describe the steps to be taken to establish a validated quantification method for psychoactive compounds within complex plant matrices through its application to the detection and quantification of atropine in Datura stramonium seeds. Six calibration standard series are analyzed eight times over a period of several days to create a calibration curve. The resulting calibration curve is tested using six quality control samples and finally utilized to determine the concentration of atropine in a D. stramonium seed extract. The linear range for quantification of atropine in this study was found to be comparable to that reported previously using GC, LC, HPLC, and UHPLC-MS methods. Furthermore, the method can be applied to the quantification of other biomarkers in plant materials, despite the complexity of the plant matrix. The speed of the analysis (<10 minutes for duplicate analysis of 20 samples) and the ability to integrate peaks using accurate masses for specificity are advantages of the DART-HRMS quantification approach.