Thermal analysis and ion mobility coupled to high-resolution mass spectrometry for organic aerosol characterization

• Applicant: Professor Dr. Ralf Zimmermann
• Subject Area: Analytical Chemistry ; Atmospheric Science
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 446129707

Anthropogenic air pollution exposes the environment to a large number of organic contaminants with severe health and climate impacts. The major impact on humankind and the tremendous molecular complexity of organic aerosols motivates the development of novel analytical instrumentation approaches.The envisioned three-year corporate effort between the University of Rostock (Germany) and the University of Rouen-Normandy (France) primary aims to develop a set of evolved gas analysis (EGA) techniques coupled to state-of-the-art mass spectrometry (MS) platforms for the detailed chemical description of primary and secondary organic aerosols. In this respect, the shared expertise in high-resolution MS will make Fourier-transform ion cyclotron resonance (FT-ICR) and high-resolution time-of-flight MS the central analytical platforms and allow for molecular-level insights. Three main EGA approaches will be utilized for hyphenation: Atmospheric solids analysis probe (ASAP/DIP), thermal-optical carbon analyzer (TOCA), and gas chromatography (GC). Vital, ion mobility spectrometry (IMS) will serve as an additional separation technique for size and shape of the evolved constituents.The information from the different approaches aims to reach three main achievements: 1) insights into the isomeric complexity of organic aerosols, 2) description of the chemical moieties at the molecular level, and 3) chemical comparison of primary emissions and those formed by chemical reactions (secondary, aged aerosols). Structural information is gained by the combination of GC retention time, selective ionization techniques (e.g., photoionization targeting aromatic species), fragmentation pattern (both by ASAP and tandem mass spectrometry), and ion mobility response. For this purpose, adapted data processing strategies will be developed, among others, including the theoretical computation of collision cross-sections (CCS).Finally, this will allow us to set up a molecular repository for different types of aerosol sources, with a particular focus on shipping emissions. This molecular library is foreseen to be suitable to link human health aspects or to contribute to the understanding of the respective climate influence of particulate matter.

• DFG Programme: Research Grants
• International Connection: France
• Partner Organisation: Agence Nationale de la Recherche / The French National Research Agency
• Cooperation Partner: Professor Carlos Afonso, Ph.D.