Development of a simultaneous multi component analytical method for 37 new psychoactive substances in wastewater using LC MS/MS

Abstract

A simultaneous multi–component analytical method for 37 New psychoactive substances (NPS) in wastewater using LC–MS/MS was developed in this study. Cartridge and solvent tests were conducted to establish the optimal method taking into consideration the polarity and acid–base characteristics of widely distributed NPS. The most efficient pretreatment method was to use HLB cartridge with 2% Formic acid in methanol elution solvent. The developed analytical method was validated by evaluating its specificity, linearity, accuracy, precision (intra and inter), and robustness. The r2 of calibration curves ranged from 0.9969 to 0.9999, ensuring linearity within the concentration range of 0.5–100 ng/mL. The accuracy for 37 compounds ranged from 72.2 to 114.7%, with an intra–day precision ranging from 0.45 to 11.63% and an inter–day precision ranging from 0.96 to 17.99%. The MDL was in the range of 0.01–2.91 ng/L and the LOQ was 0.03–9.71 ng/L. Robustness was evaluated to test the stability of the final solutions, and all compounds were assessed over 36 h and 30 days. The developed analytical method was applied to wastewater samples collected from six Korean WWTPs, and five compounds were detected. © 2024 Korean Society of Environmental Engineers.