MRI: Acquisition of high-resolution mass spectrometry system for metal-organic environmental and biological chemistry

Metals have a major impact on the health of the ocean, soils, and watersheds. Many metals are essential nutrients for life that often limit biological activity, while others are harmful contaminants from human activities. The biological uptake, toxicity, transport, and treatment of metals is largely controlled by molecules produced by microbes and plants that bind to these metals and keep them in solution. While it is widely recognized that many dissolved metals are mostly present as organic-bound forms in the environment, determining the composition, origin, and fate of metal-binding organic molecules is an analytical challenge due to the highly complex chemistry of environmental waters. The investigators in this study will acquire a liquid chromatography mass spectrometry instrument to enable new research on the origin and fate of organic molecules that govern metal distributions in the ocean, pathways for the microbial processing of metals, the reactions between metals and organic matter in soils, the design of improved water treatment systems that remove harmful metals associated with organic matter, and the development of machine learning approaches for environmental forensics. The instrument will also provide hands-on training of the next generation of environmental analysts through workshops and projects involving high school, undergraduate, graduate, and postdoctoral students.Low concentrations of iron and other micronutrient metals limit productivity across large sections of the ocean, but their chemical forms are largely unknown. This high resolving power mass spectrometry system will be used to separate and identify organic molecules and their isotopologues encountered in ocean waters. As part of the US GEOTRACES program, we will measure trace metal and organic speciation across the Southern Ocean and Antarctic shelf. This work will provide mechanistic insight into the processes that supply micronutrients to surface waters of the chronically metal limited Southern Ocean. We will also investigate the speciation of metals and organics sourced from coastal sediments, groundwater and microbial laboratory cultures to establish linkages between specific organisms/genes and metal binding metabolites that govern metal solubility and uptake across diverse environments. Furthermore, we will determine speciation of copper and other anthropogenic metals in river and wastewaters in order to assess toxicity and removal strategies. Another focus of our research will be to develop machine learning algorithms to develop markers of environmental processes based on high resolution mass spectrometry data. Such advancements have the potential to transform knowledge of elemental cycling from empirical descriptions to mechanistic models that better explain and predict environmental processes by accounting for chemical and biological diversity.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.