Rapid Identification of New Psychoactive Substances in Letters by LA-APCI-MS

New psychoactive substances (NPS), especially synthetic cannabinoid receptor agonists (SCRA), are increasingly smuggled into prisons via infused mail. Consumption of those substances by inmates in prisons is associated with increased aggression, violence, and organized crime. Onsite detection of infused mail often is challenging. Because the infused papers do not show any visible stains or olfactory changes, physical inspection is often insufficient. The applicability of further conventional on-site detection methods like immunoassays and sniffer dogs is severely limited. Because of the rapidly changing supply of already circulating and newly emerging NPS, it is impractical to impossible to keep up with the development of immunoassays or the training of sniffer dogs. Hence, confiscated mail samples are routinely tested by either liquid chromatography or gas chromatography coupled to mass spectrometry (MS), which is costly and time-consuming. In this study, recent advancements in the hyphenation of laser ablation (LA) and molecular MS were investigated regarding the possible application for the rapid and easy detection of NPS in prison mail. Utilizing an in-house developed LA-MS hyphenation based on atmospheric pressure chemical ionization (APCI), 31 mail samples confiscated in German prisons were analyzed. It was possible to correctly identify 27 samples containing SCRAs. For these positive samples, it was also possible to detect the specific compounds each paper was infused with. The use of LA-APCI-MS has simplified sample preparation and reduced analysis time per sample to 1 min.