Our Research

My group studies how organic compounds’, both natural and anthropogenic, cycling affect biological and ecological processes and vice versa. These interconnected processes are important drivers for organic carbon and contaminant cycling at regional and global scales. We use untargeted and targeted analyses as well as data science to shed light on different aspects of organic biogeochemistry. Besides the typical organic carbon moieties (i.e., containing C, H, O, N, S, and P), we are particularly interested in those containing halogens (thus the group name is Halo-Carbon)! 

Untargeted Analysis – Hunting the Unknown Compounds. We use advanced analytical chemistry (e.g., ultrahigh-resolution mass spectrometry) and novel compound identification algorithms to characterize environmental complex organic mixtures at a molecular level. The detailed chemical information allows us to look beyond the known molecules and search for the previously unknown compounds to better understand various processes, for example:

(1)   how halogenation of natural organic matter affect carbon cycle and ozone chemistry;

(2)   how microbes transform water-soluble crude oil components in seawater, after an oil spill;

(3)   how organic carbon transform and cycle in the environment.

Targeted Analysis. We use targeted analysis to study various environmental issues. For example, currently, we are investigating the environmental distributions of the “forever compounds,” known as the per- and polyfluoroalkyl substances (PFAS), as well as pharmaceuticals and personal care products (PPCPs). 

Data Science. We use data science pipelines to discover and classify organic compounds and fingerprint environmental samples. We use novel computational algorithms to decipher the complex data generated from ultrahigh-resolution mass spectrometry. For example, the Isotope Pattern Algorithm (IPA; developed at the Pacific Northwest National Laboratory) allows us to “hunt” for unknown compounds that contain halogens. Currently, we are working on a cheminformatics pipeline to fingerprint and classify tarballs. 

Field and Laboratory Studies. We use both field and laboratory studies to achieve our research goals. Sometimes, even computational modeling.