Mass accuracy, sensitivity, and selectivity of high resolution mass spectrometers enable the application of targeted and non-targeted analysis using a data dependent or data independent acquisition modes. The work presented here addresses the challenges encountered in the analysis of trace levels of several classes of environmental contaminants in surface and wastewater samples using liquid chromatography mass spectrometry (LC-MS) system. The previously validated method in the triple quadrupole LC-MS/MS was transferred to the Orbitrap LC-MS system. A list of precursor masses were used to trigger the fragmentation of target and suspect analytes. Quantitative results of targeted analysis were compared between the triple quadrupole system in selected reaction monitoring (SRM) mode and the Orbitrap LC-MS system. Comparison of the results of the two systems helped in the assessment of false negative results. Performance of different acquisition modes in the Orbitrap were also assessed by comparing results acquired using parallel reaction monitoring (PRM), all ion fragmentation (AIF), and data dependent MS2 (ddMS2), with and without an inclusion list. In-house suspect screening database of six classes of environmental contaminants commonly analyzed in water samples was developed. A suspect screening analysis of surface and waste water samples that were previously analyzed for targeted analysis was performed using full-scan with ddMS in negative and positive modes. Data were processed and analyzed using trace finder. Results from the non-targeted analysis revealed several contaminants present in the water samples that were not previously being monitored in the target analysis.

In-house suspect screening database as a tool to increase detection coverage for analysis of contaminants in environmental samples

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.