Untargeted Screening of Per- and Polyfluoroalkyl Substances by HRAM-DIA Method on LCMS-9030

User Benefits

- A sensitive untargeted screening method was established based on HRAM-DIA data acquisition on LCMS-9030. The method was successfully verified with 14 PFAS standards at 1 ng/mL in water. - Data analysis was performed using LabSolutions Insight Explore^TM – Analyze. PFAS-like species could be extracted by specific elemental settings which function as mass defect filtering for PFAS. This procedure was used for an unknown sample, and 16 PFAS-like species were discovered and characterized.

Introduction

Contamination of per- and polyfluoroalkyl substances (PFAS) is found everywhere in the water, soils, sediments, fish, foods, textiles and human blood etc. Targeted screening and quantitation of PFAS in drinking water by LC-MS/MS are established in reference to the US EPA Method 537 and ISO 21675: 2019, ASTM D7979 etc. Such MRM-based methods are widely adopted in the analysis of up to 29 PFAS or more. However, PFAS represents a large collective of compounds and many of them are not determined by the existing methods. This study aims to establish a method of untargeted screening for both known and undiscovered PFAS in water samples. The method was established based on LC-Q-TOF data, i.e., HRAM spectrum (MS) and DIA deconvolution spectrum (MS/MS), relying on the specific mass defect feature of PFAS using LabSolutions Insight Explore – Analyze program. Fourteen PFAS including PFOA and PFOS were used as standards for verifying the performance of this HRAM-DIA method in terms of detection sensitivity and identification. The established approach was applied to real water sample analysis and the found PFAS-like species were further characterized via database and library searches, and structural elucidation using LabSolutions Insight Explore – Assign program.

November 24, 2022 GMT