WEBINAR - Investigation of PFAS Fingerprints Using the World’s Highest-Resolution 21 Tesla Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry

Employ the world’s highest-resolving mass spectrometer coupled with algorithm-assisted statistical analysis to extract PFAS fingerprints for a comprehensive analysis of the environmental impacts.

Dr Wenchao Lu from CSIRO Environment will present his most recent progress on using world’s highest-resolution mass spectrometer to evaluate PFAS contaminants in samples, which will provide unprecedent insights into PFAS fingerprints.

He and his colleagues have used the 21 Tesla Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) to examine AFFF samples in both negative and positive electrospray ionization (ESI) mode. This cutting-edge technique facilitates precise measurement of molecular mass with an error below 0.2 ppm (<0.1 mDa). The molecular formula assignments based on accurate mass were done using high-efficiency python algorithm, reinforced by supplementary gauges such as isotopologues, homologues, and mass defects. This approach expedites a fast and accurate molecular formula assignment and enables a rapid identification of all CF2, CH2, and C2H4O homologous series.

Their findings include that in negative ESI mode, PFAS have both shorter and longer fluorocarbon chains, featuring numerous CF2 homologous series. In contrast, PFAS in positive ESI mode predominantly possess shorter fluorocarbon chains with a limited presence of CF2 homologous series, which appear as side chains or quaternary ammonium adducts in association with hydrogen-rich natural organic molecules. In conjunction with the application of statistical and network analyses, they have analysed up to 3,700 PFAS at 4 confidence levels, promoting fingerprinting of PFAS and their transformed molecules. These findings will be effectively used for discriminating various sources of PFAS and tracking pathways of contamination. Their approach not only offers a comprehensive analysis of PFAS contaminants in environmental matrices, but also suggest their hydrological dynamics across different samples. Furthermore, this research lays the groundwork for future studies on the evolution of PFAS contaminants in the natural environment for a broader impact.

Our Speaker

Dr Wenchao Lu,
Research Scientist,
CSIRO Environment

Dr. Wenchao Lu is a research scientist at CSIRO Environment, where he focuses on evaluating the influence of per- and polyfluoroalkyl substances (PFAS) in the environment and seeking solutions to mitigate the impact. His expertise includes using ultrahigh-resolution FT-ICR mass spectrometry coupled with algorithm-assisted big-data analytics for PFAS non-targeted analysis, and using experimental and theoretical approaches to investigate the incinerability of PFAS. Prior to joining CSIRO, Dr. Lu worked as a postdoctoral researcher of physical chemistry at Lawrence Berkeley National Laboratory in California, USA. His previous research includes the singlet oxygen oxidation dynamics of small biomolecules, the growth mechanism of polycyclic aromatic hydrocarbons in the gas phase, and weak intermolecular forces based molecular cluster chemistry.