Advances in Paper Spray Mass Spectrometry (PS-MS) for On-Site Harm Reduction Drug Checking and Illicit Supply Surveillance

Harm reduction drug checking utilizing paper spray mass spectrometry (PS-MS) has been the focus of ongoing research since 2017 and has seen many refinements. The presented work is the result of this research and has led to the public-facing PS-MS use for on-site drug checking in Victoria, BC. Included are the improved methods and approaches required to develop and implement PS-MS as an on-site drug checking technology. Critical details regarding appropriate direct mass spectrometry tune and calibration suites required to avoid isobaric interferences, calibration details, quality control strategies, detailed MS scan approaches to implement rapid drug tests, as well as future work considerations are presented. The PS-MS method presented currently directly quantifies 107 targeted drugs in a two-minute measurement, and can be easily adapted to include additional new targets that appear in the unregulated drug supply that are detected by either low or high resolution PS-MS. The presented methodologies provide a framework to assist those interested in implementing PS-MS to reduce harms from the toxic drug supply, but will have value for those developing rapid, quantitative drug testing for other applications.