M.Sc topic: Isotopic Fingerprints of PFAS: Development of a novel Forensic Analysis Method using Orbitrap - Stuttgart

Per- and polyfluoroalkyl substances (PFAS) pose a serious environmental threat due to their persistence, mobility, and toxicity. Despite increasing regulatory efforts, there is currently a lack of effective forensic tools to trace contamination sources and apply the polluter-pays principle. This master’s thesis aims to develop an innovative compound-specific isotope analysis (CSIA) method for PFAS using high-resolution Orbitrap mass spectrometry (HRMS). The focus will be on establishing reliable analytical protocols for selected PFAS starting with TFA, and potentially with PFBA, PFBS, PFOA and PFOS, with an emphasis on quantifying stable carbon (13C/12C), sulfur (34S/33S/32S) and oxygen (18O/16O) isotope ratios. The thesis includes the systematic development of Orbitrap-based CSIA methods (optimizing ionization, scan parameters, and fragmentation behavior) for selected PFAS. The ultimate goal is to generate reproducible isotopic “fingerprints” that allow for source attribution dependent on production methods or degradation processes. The results will support environmental forensic investigations, help identify responsible polluters, and contribute to more targeted and effective remediation strategies. The master thesis offers a unique intersection of environmental chemistry, high-resolution mass spectrometry, and applied environmental science.

Prospective Tasks

▪ Literature review on CSIA, HRMS and the application of HRMS to measure stable isotopes.

▪ Systematic HRMS-CSIA method development for TFA (+ other compounds) and data evaluation

▪ Development of Step-by-Step guides to apply the methods

▪ Visualization of results and discussion