The Environmental Chemical Sciences (ECS) program of the Division of Chemistry will support the research program of Prof. Christy Haynes of the University of Minnesota. Prof. Haynes and her students will study the interaction of beneficial bacteria with engineered nanoparticles and assess the role that simulated natural water has on nanoparticle characteristics and bacterial impact. Initial efforts will focus on characterizing nanoparticle behavior in simulated natural water by studying nanoparticle dispersity and stability in the presence of natural organic matter (NOM) while also working to understand transformations the NOM experiences after nanoparticle introduction. Furthering mechanistic understanding of bacteria-nanoparticle interactions, the next stage of the study will address how nanoparticle presence influences S. oneidensis function, namely biofilm formation and flavin secretion. These functions have numerous constructive impacts on the ecosystem, and disruption by nanoparticles would be significant. The study addresses the critical gap in ecological toxicity knowledge surrounding the interaction of commonly used engineered nanoparticles and the beneficial bacteria, S. oneidensis. The nanoparticles chosen for investigation, TiO2 and Ag, are likely candidates for unintentional release into the aquatic ecosystem because of their common use in consumer products. Within the food web, the interaction of engineered nanoparticles with beneficial bacteria is important based on the constructive function of bacteria itself as well as their interaction with other organisms. It is critical, therefore, to consider how ecologically important organisms are impacted by these nanomaterials. S. oneidensis is an ideal model beneficial bacteria because they are widely distributed, geographically and throughout the aquatic ecosystem.
As a part of the project, Prof. Haynes and her students will develop a high school laboratory activity titled, "Nanoparticle Toxicity in Brine Shrimp" where students will get a hands-on experience examining the effects of noble metal nanoparticles on an aquatic invertebrate. They will learn concepts from chemistry, microbiology, and statistics, while exploring this cutting edge topic. The research project will provide excellent educational opportunities for students, including some from underrepresented groups, desiring to work at the forefront of environmental science.
