Research
![Multiphase processes influencing the Earth system, climate, life, and public health over a wide range of spatial and temporal scales: chemical reactions, mass transport, and phase transitions between gases, liquids, solids, and semisolid substances involved in molecular and cellular interactions as well as in regional and global fluxes of biogeochemical cycling](/5589878/original-1723724972.jpg?t=eyJ3aWR0aCI6MjQ2LCJvYmpfaWQiOjU1ODk4Nzh9--3a4ce6ff9f51178b048d42d6696aef79099487d1)
Multiphase chemistry deals with reactions, transport, and transitions between different phases of matter such as gases, liquids, solids, and semi-solids. These processes are essential for the Earth system, climate, life, and public health. Prominent examples are the formation of clouds, rain, and snow or the respiration of humans, animals, and plants.
From a chemical perspective, life and the metabolism of living organisms can be regarded as multiphase processes that transform and exchange gases such as oxygen, nitrogen oxides, and carbon dioxide; liquids such as water, blood, and lymph; and solid or semi-solid substances such as bone, skin, and cellular membranes. The global biogeochemical cycling of chemical elements and compounds, which constitutes the metabolism of planet Earth, also involves multiphase chemical reactions, mass transport, and phase transitions within and between the atmosphere, biosphere, hydrosphere, and lithosphere/pedosphere.
The overarching aim of the Multiphase Chemistry Department is to elucidate the role of multiphase processes that are essential in the interplay between air pollution, climate, and public health in the Anthropocene, i.e., in the present era of globally pervasive human influence on planet Earth. Key research topics addressed in the department include the transformation and environmental effects of primary biological and secondary biogenic aerosols as well as the chemical mechanisms, environmental causes, and mitigation of oxidative stress, allergies, and related inflammatory disorders.
To explore and resolve these issues, we combine physical, chemical, and biomedical techniques in laboratory experiments, field measurements, and model studies at the interface of Earth and life sciences. We develop and apply advanced experimental and theoretical methods, including bioassays and DNA analyses, microscopic and spectroscopic techniques, and kinetic process models.
The current main areas of research are broadly reflected by the titles of the research groups, laboratories, and project teams in the Multiphase Chemistry Department: Aerosol Analysis and Microscopy (C. Pöhlker et al.), Biomolecular Analyses and Interactions (J. Fröhlich et al.), Chemical Kinetics and Reaction Mechanisms (T. Berkemeier et al.), Organic Pollutants and Exposure (G. Lammel et al.), Multiphase Analytics (F. Drewnick), and Aerosol Surface Emissions and Transport (F. Fachinger). Detailed information about recent results and ongoing research in each of these subject areas are detailed on the corresponding web pages. We collaborate closely with other departments and research groups at the institute as well as alumni and research partners around the world.
Common themes and focal points include bioaerosols, proteins, and allergens; cloud condensation and ice nuclei; reactive oxygen and nitrogen species; and contrasts between pristine rainforest and polluted megacity environments. Highlights and perspectives of recent and ongoing research activities are detailed in the project and group reports on the corresponding web pages. They comprise deep insights into the sources and interactions of aerosols in the Amazon rainforest; redox reactions, protein modifications, and oxidative stress in epithelial lining fluid; and chemical modulations of inflammatory immune responses.
In collaboration with international partners, we use and operate major research platforms for Earth system studies, such as the Amazon Tall Tower Observatory (ATTO), the German High Altitude and Long-Range Research Aircraft (HALO), and the S/Y Eugen Seibold (SYES) research yacht. Regional and global model simulations are performed in collaboration with the Atmospheric Chemistry Department (J. Lelieveld et al.) and with the independent Minerva Research Group/Aersol Chemistry Department (Y. Cheng et al.). During the COVID-19 pandemic, we also pursued scientific studies and outreach to help elucidate the transmission of SARS-CoV-2 by respiratory particles and mitigate their spread by protective measures as outlined on the corresponding pages.