CONDESA: Protecting vital natural resources through the power of nanomaterials

As climate change continues to impact communities and ecosystems, scientists need more sophisticated and effective tools to measure and analyze the vitality of critical natural resources —including soil, water and air.

The U.S. National Science Foundation Research Traineeship (NSF NRT) program Convergence of Nano-engineered Devices for Environmental and Sustainable Applications (CONDESA) at the University of California, Merced is driving innovation in this work using nanomaterials to create and leverage economical, multifunctional sensors that can help measure the health of air, soil, and water over time. CONDESA is not only developing cutting-edge environmental sensors but also cross-training students in molecular biology, physics, chemistry, environmental science and sustainable systems to create a new generation of nano-engineers prepared to assess and solve environmental health and sustainability problems.

Principal investigator Sayantani Ghosh reflects on the significance of this innovative NSF NRT program below, followed by comments from two former trainees, Shelby Defeo and Jorge Arteaga, who share their perspectives on the power of the program and their plans for the future.

Q: Dr. Ghosh, can you talk about the research happening because of your NRT, and the promise of nanomaterials in terms of protecting our environment?

A: One of the things we're working on is detecting nitrate content in soil. Nitrates are derivatives of ammonia, and they come from various processes, but one of them is when people add fertilizers to the soil. It gets into water, air and soil and is damaging in high concentrations. Currently, the way environmental folks study the soil content is that they go to the field, collect massive amounts of soil samples, and then they bring them back to the lab and analyze them over months using very complicated procedures. In the meantime, while they're doing the testing over months, the real nitrate levels are constantly in flux. Because all the data you get is averaged over many months, by the time tests are completed, the results are outdated. That is what we are trying to address — determining how we can make easy, cheap, lightweight sensors that let us track nitrate levels in real time.

This has a direct impact on our immediate community. UC Merced has a large agricultural community, with many farms and ranches. We are talking to a lot of folks, including an almond farmer who uses nitrate fertilizer. We were visiting his farm, and he told us he decides how much fertilizer to use based only on his yield of almonds, though he said he knew "there has to be a better way of doing this." We're focused on creating more effective tools that can help lessen negative impacts on our air, water and soil.

Q: How does that real world experience affect trainees' training?

A: These students had never been out to farms before this — they go as part of this project over the summer. They visited, and they found out about these sorts of real-life problems and what really needs addressing. It has a significant impact when you step away from a lab situation, where conditions are perfect and predictable, and instead must adjust to real-world circumstances. Determining what needs improvement and talking to real people has a powerful impact.

Q: What initially motivated or inspired you to apply for an NRT?

A: We applied because the NRT program emphasizes interdisciplinary research for graduate students. It is becoming increasingly clear that for the jobs that students want to do — since most don't want to go into academia — they need to be able to lead teams of researchers who speak different languages. As faculty, we tend to emphasize publishing papers because that productivity benefits us — but that doesn't necessarily support student training. The NRT program gives us the legitimacy to focus on giving students opportunities to learn the language of another field so that they can generally work in that area, particularly in industry. And it also gives faculty the resources to develop new courses; you get buy-in from different departments to develop team-taught courses. All of these become much easier to do when you have a platform to do it from, and that's what the NRT program provides.

Q: Why is the interdisciplinary component so crucial?

A: Our program has physics, chemistry and material students on one side, and environmental systems students on the other side, because we are trying to design sensors for field deployment in different geo-environments. These two sides speak entirely different languages. The materials folks don't really understand what is needed to use them in the field and how to make it deployable; our focus is entirely on lab-based applications. Environmental folks know what they need, but they don't have the means to drive the design process. With the NRT program, someone on the materials side can say, "Well, I can build that if you want to take it out and test it." That kind of connection across disciplines is exactly what we want.

I think this generation of students is conscious about social justice and climate issues, but they don't necessarily know how their research can play a supportive role. So this opportunity is very exciting for them, because it provides hard science students with an understanding of how their work can support our environment. Now they feel like they have a role to play, and that opens up the career opportunities they can pursue.

"Nitrates in water is a very contentious issue here in the Central Valley, where a lot of farmers don't believe they're the ones necessarily polluting the groundwater. What's really interesting is that the development of this sensor, through the NRT program, is attractive to multiple parties who come at this issue from different viewpoints and with seemingly opposite purposes, including farmers themselves and those concerned about water quality and environmental preservation. I'm really excited about the prospect of creating something that works for all those groups. And I feel lucky to be able to participate in these kinds of experiences that most graduate students don't have the opportunity to pursue."

Shelby Defeo, former NRT trainee

"This fellowship has opened a path that I never would have thought of for this material that's very rarely used for sensing. The NRT program's interdisciplinary approach is very different from anything I've done before — and I think it's very valuable because it opens your mind to thinking about your field from someone else's perspective. I think one of my biggest takeaways from the first year was the power of working with other researchers from different fields who view the project from different directions. It took some time to get on the same page and see things in the same way. I think that was very beneficial, because it takes you out of this box that you're used to thinking in. As a physicist, I'm used to reading physics papers and only thinking about things in a certain way, but seeing these issues from an environmental approach, it opens your eyes to your research from a variety of applications and perspectives. That's something that I wouldn't have gotten anywhere else."

Jorge Arteaga, former NRT trainee