Surface Partitioning, Structure, Properties and Reactivity of Biological Macromolecules in Aqueous Aerosols and at the Air/Water Interface: Theory and Experiment

This award supports Professors Vicki Grassian and Rommie Amaro at the University of California-San Diego to investigate the chemistry of biological macromolecules, including nucleic acids and viruses, in aqueous aerosols and at the air/water interface. Bioaerosols containing nucleic acids and viruses have profound impact on public health as vectors of disease transmission yet there are significant gaps in understanding the behavior and chemistry of biological macromolecules in aerosols, especially aqueous aerosols and at the air/water interface. These gaps include understanding the impact of aerosol pH on the surface propensity of these biological macromolecules as well as how these biological macromolecules transform in the environment. Professors Grassian and Amaro and their students integrate experiments and theory to address key questions on surface partitioning, structure, properties and reactivity of nucleic acids and viruses as a function of composition and environmental conditions, including interactions with oxidants and solar radiation. These studies provide molecular-level insights needed to predict the behavior of nucleic acids and viruses in aqueous aerosols and at the air/water interface to address critical gaps in knowledge from both atmospheric chemistry and public health perspectives. The training and mentoring of students in rigorous scientific inquiry utilizing state-of-the-art theories and experimental methods are important aspects of the research along with outreach efforts to general audiences to educate the public through engagement in different venues. A tightly integrated experimental and theoretical collaboration between the Grassian Group, with expertise in aerosols and interfacial chemistry, and the Amaro Group, with expertise in molecular dynamics and computational chemistry, will enable a molecular-to-macroscopic understanding of the chemistry and behavior of nucleic acids and viruses in aerosols and at the air/water interface. Specific investigations include: (i) determining how aerosol pH varies with atmospheric CO2 concentrations relevant to indoor and outdoor environments; (ii) determining surface partitioning, structure, and properties of nucleic acids (RNA and DNA) and virus like particles and how their structural and physicochemical properties are shaped by aerosol composition, including pH, by integrating experiments and simulations to reveal molecular mechanisms driving interfacial behavior; (iii) measuring reactivity with environmental stressors by exploring how oxidants (O3 and NO2) and solar radiation alter the structure, reactivity, and surface propensity of biomolecules in aerosols and simulating how environmental stressors can degrade or modify biological macromolecules, influencing both aerosol properties and their role in atmospheric chemistry and disease transmission pathways. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2603162 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: Vicki Grassian | Institution: University of California-San Diego, LA JOLLA, CA | Award Amount: $750,000 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2603162 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2603162.html