A comprehensive UHPLC–MS/MS screening method for the analysis of98 New Psychoactive Substances and related compounds in human hair

tIn this study, a rapid liquid chromatography-tandem mass spectrometry (LC–MS/MS) method has beendeveloped and validated for the targeted analysis of 98 New Psychoactive Substances (NPS) from thehair matrix. The monitored compounds included various chemical classes (7 phenethylamines, 10tryptamines, 18 cathinones, 24 synthetic opioids, and 38 synthetic cannabinoids) with emphasis givento newly emerged NPS. The method employed a direct extraction process through the incubation of hairsamples (25 mg) and internal standards with M3®reagent at 100◦C for 60 min, followed by extractpurification through acid and basic liquid-liquid micro-extraction (LLME). Extracted compounds wereanalyzed through LC–MS/MS system operating in multiple reaction monitoring mode. NPS were sepa-rated in 9.5 min with a Poroshell 120 EC-C18 column (2.7 m, 4.6 × 50 mm) using a gradient elutingmobile phase composed of water and acetonitrile/water (95:5) both containing 0.1 % of formic acid. Thedeveloped and validated method shows a good precision (≤ 15 %), linearity (R2between 0.993 and 0.999),selectivity, and sensitivity (LOD: 0.6–10.3 pg mg−1and LOQ: 2.1–34.4 pg mg−1). The method showed alsoreduced matrix effect and acceptable recovery for most of the targeted compounds. Our results showedthat this method is suitable for quantifying NPS in hair matrix and could be employed in the context ofroutine analyses in analytical laboratories.