We apply fundamental chemical principles to understand the fate and behavior of metal and organic compounds in complex environmental matrices.
Engineered nanomaterials (ENMs) and nanotechnology will be an important tool for making agriculture more resilient and sustainable. We are working to understand how size, coating chemistry, solubility, and bio-recognition molecules can be used to deliver engineered nanomaterials to specific locations inside of plants. We aim to produce nano-enabled agrochemicals that safely and efficaciously promote plant health, suppress disease, increase tolerance to climate-induced stresses (heat and salinity), and increase the utilization efficiency of agrochemicals. The fundamental understanding of fate processes of ENMs also improves environmental health and safety assessment of ENMs.
- How do ENM properties affect leaf adhesion, uptake, and transport in leaf tissue?
- What ENM properties can promote phloem loading and transport to other parts of the plant?
- How can ENMs target important organelles in plants, e.g. chloroplast?
Avellan, et al. Nanoparticle size and coating chemical identity controls pathways of foliar uptake, translocation and leaf-to-rhizosphere transport in wheat plants. ACS Nano 13 (5) 5291-5305. https://pubs.acs.org/doi/10.1021/acsnano.8b09781
Spielman-Sun, et al. Temporal evolution of copper distribution and speciation in roots of Triticum aestivum exposed to CuO, Cu(OH)2, and CuS nanoparticles. Environ. Sci. Technol. 52 (17), p. 9777–9784. https://pubs.acs.org/doi/10.1021/acs.est.8b02111
Determining the sources of environmental contaminants can help in understanding the processes that influence their overall fate and impacts. We use single particle inductively coupled plasma time-of-flight mass spectrometer (spICP-TOF-MS) to determine the precise chemical compositions of individual particles in environmental and biological matrices. We use machine learning approaches to fingerprint the particles in order to link them to their sources and to track changes in their composition over time.
- What chemical fingerprints of natural and engineered nanomaterials can be used to identify their sources and distinguish them from natural NMs?
- How do natural weathering and microbiological processes affect these fingerprints?
- How can we develop efficient machine learning techniques to identify these fingerprints in soil samples?
Effect of Hg Speciation on fate and removal
Hg speciation controls its environmental fate and its toxicity potential. Mercury speciation is also highly variable and dependent on its local solution biogeochemcial conditions. We use laboratory experiments and X-ray synchrotron analyses to understand how Hg speciation affects its fate in industrial processes and the environment.
Avellan, A., et al., Speciation of Mercury in Selected Areas of the Petroleum Value Chain. Environ. Sci. Technol. 52 (3), pp 1655–1664. https://pubs.acs.org/doi/10.1021/acs.est.7b05066
Gai, K. et al., Impact of Hg Speciation on its Removal from Water by Activated Carbon and Organoclay. Wat. Res. 157 p. 600-609. https://www.sciencedirect.com/science/article/pii/S0043135419303100