Use of Non-Targeted Workflows for the Analysis of Pharmaceutical and Illicit Drug Occurrence in Environmental Samples

Advances in High Resolution Mass Spectrometry and Its Emerging Environmental Applications
Poster Presentation

Presented by R. Marfil-Vega
Prepared by N. Loftus1, J. Dahl2, R. Marfil-Vega2, L. Barron3, A. Barnes1
1 - Shimadzu, Wharfside Trafford Wharf Road, Manchester, Manchester, 00000, United Kingdom
2 - Shimadzu Scientific Instruments, 7102 Riverwood Drive, Columbia, MD, 21046, United States
3 - Imperial College London, School of Public Health, , London, United Kingdom


Contact Information: neil.loftus@shimadzu-mso.com; 800-477-1227

ABSTRACT

High resolution LC-MS/MS methods were applied to the analysis of wastewater and river water samples taken from a heavily urbanized tidal river catchment area (London, UK). In this work, precursor ion data in full scan MS mode and data independent analysis (DIA) product ion detection in MS/MS mode were acquired with Shimadzu’s LC-QTOF 9030 to support both targeted and suspect screening analysis. Using a targeted data analysis workflow, a number of illicit drug and pharmaceutical compounds were positively identified. Confirmation of each target was done four parameters: accurate mass, isotopic distribution, retention time and accurate mass fragment spectrum data; to help on this task a curated accurate mass MS/MS data base with over 900 compounds including retention times was used to increase reporting confidence. This approach positively identified commonly reported illicit street drugs such as cocaine and lidocaine (regularly used as an adulterant in illicit street drugs) and a number of antidepressant’s including selective serotonin re-uptake inhibitors (citalopram, fluoxetine, sertraline). A suspect screening workflow was applied to the already acquired data to search for compounds not included in the initial target list. A series of tools were used in this workflow, including component detection (to locate all ion signals in the sample), suspect screening search lists (to match molecular ion features), molecular formula prediction and to verify a putative candidate from a chemically-indexed database (such as PubChem or ChemSpider) a fragment structural annotation tool was used to correlate acquired MS/MS fragment structures with the molecular structure. Using this analysis, several other compounds were detected in the wastewater samples including serotonin and norepinephrine reuptake inhibitors such as venlafaxine.