Screening of 150 Drugs and Toxic Compounds in Urine by Ultra-High Performance Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry

A method for screening of 150 drugs and toxic compounds in urine by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS^E) was proposed. Urine samples were prepared by liquid liquid extraction, then separated on ACQUITY UPLC HSS C₁₈ column, with mixtures of acetonitrile solution containing 0.1% (volume fraction) formic acid and 5 mmol·L^-1 ammonium formate solution (pH 3.0) at different volume ratios as the mobile phase for gradient elution. The positive ion mode of electric spray ionization was applied and full scan mode was used for screening. 150 compounds were identified according to their retention time and the information of parent ions and fragment ions. As shown by the results, there were 13 isomers in 150 compounds, and 10 out of 13 isomers could be successfully distinguished from each other based on different retention time or unique fragment ions. The detection limits (3S/N) for 150 compounds in urine were in the range of 0.2-25.0 μg·L^-1. The absolute matrix effects for 68 representative compounds ranged from 23.1% to 119%, and the extraction recoveries ranged from 30.8% to 115%. This method was used for screening analysis of 120 actual urine cases, and 10 samples were positive.