Chemical interactions
An interview with Reuben Hudson
One of the best parts of being the editor of COA is I get to spend time talking to my colleagues about the work they do at the college. What a gift, being forced to spend time listening to really smart, engaging people talk about their passions.
I loved my time as a college student—once I actually accepted that role—and I wanted to be nothing else. I spent many years getting my BA, many more getting my MFA… I would do it all again. The spaces where talking and listening and learning happen are charged spaces, magical spaces, (un)safe spaces. Spaces like that have always been a draw for me. COA is a space like that.
Enjoy the Reciprocity
—Dan
Students taking a sediment core sample.
I remember driving across the Penobscot Narrows Bridge, turning right, and thinking I have never been this way before... The rugged beauty, the sunlit hilltops, and the variety of Trump signs was more than I was used to around Bar Harbor. Strange Maine, indeed. I was heading to Monroe in the spring of 2020 to interview Lalage and Steven Rales Chair in Chemistry Reuben Hudson about a COVID-19 bubble course he and his spouse, Kit, were planning to teach in the fall. The idea was to select a cohort of COA students and professors to live and learn together on Hudson's property, effectively creating a pandemic-safe bubble while continuing their work as human ecologists. The property was amazing, a river running through it, a huge butternut tree, the remains of an old mill… everything fit for students and professors to explore. I was in awe of how lovely it was out there and so, when talking to Hudson via Zoom for this piece, I was reminded of how rural his place was when, in the middle of our discussion of organic chemistry, Hudson interjects, "Oh, wait a minute... I might have a tick here. Give me a second... No, that's not a tick..."
I'm sort of out of my depth talking to Hudson: He's a scientist, he lives in a rural part of the state, and he takes it as a matter of course when he sees—perhaps—a tick crawling on his leg. Aside from all of this, Hudson is also a prolific grant writer. "When I came to COA, I had about $20,000 left on a National Science Foundation grant, and I was able to buy an older gas chromatography (GC) machine. But I was so busy setting up my lab and teaching classes that I never really got a chance to use it." This all changed when Hudson got another grant from the Davis Family Foundation and was able to upgrade his older GC to a first-class version. This upgrade meant COA now had state-of-the art analytical capacity, but Hudson ran into the same problem not having the time to take advantage of or maintain the instrument. "Larger labs have a bunch of scientists or postdocs or even have full-time instrument or lab technicians who take care of that stuff, but here it was just me." So Hudson got to work again, appealing to a private donor to help fund a couple of postdocs coming to COA from war-torn parts of the world. Through the generosity of this donor, Hudson was able to bring in Sarah Kheireddine from Lebanon and, later, Anastasiia Pustovoit and Vitali Polubinskyi from Ukraine to help fellow scientists in need, to augment course offerings at the college, and to use and maintain some of COA's high tech instruments.
At this point, you may be saying to yourself, Good news, but what exactly is gas chromatography and how is it important to the work going on at the college? According to Hudson, a GC can both identify and quantify trace chemicals in different samples, which makes it ideal for both college lab classes and for conducting research in the field. Some of the field research in Hudson's lab involves getting in a canoe in the middle of a lake or pond, pushing a rod with a two-inch barrel (or "glorified straw," as Hudson calls it) several meters into the bottom sediment, then pulling out a sediment core to analyze. Hudson points out that a lot of the techniques for analyzing these cores require fairly straightforward procedures—you take your sample, bake it in the oven to see how much weight is lost, do this for every centimeter, and then examine what is left—but emerging techniques are relying more and more on state-of-the-art instrumentation like the GC.
Hudson normally uses GC to see if a chemical reaction worked. "Let's say you have starting material A and B and you're trying to make C; you can take a sample at the end and inject it into the instrument and see, okay, how much A was consumed, how much B was consumed, how much C was made... When Kit was finishing up her PhD at UMaine, she came up with the idea that we might be able to use GC to quantify the biochemical markers in core samples." In short, they tried it, and the process worked like gangbusters. According to Hudson, his lab at COA is the only one in the Northeast doing these kinds of quantifications.
Pustovoit and Polubinskyi are working on a research project with colleagues from UMaine to identify and quantify human biochemical markers in dated lake sediment zones. By using the above core sample technique, you end up with anywhere from a two- to ten-meter sediment core. In order to get an idea of the chronology of the core, Hudson notes, collaborators at UMaine will pluck out organic material like leaves, bugs, pinecones, etc. and send them away for radiocarbon dating. This gives scientists a profile of the depth and age so when they then analyze centimeter by centimeter, they can quantify some of the human biochemical markers and see if people were on the landscape at specific times. "One of the things about Maine is that there's really poor preservation of archeological sites and we have acidic soil which makes it hard to preserve cultural materials... When you have something like The Native American Graves Protection and Repatriation Act, research like this is invaluable."
The act is a mechanism for Indigenous communities to get back remains or cultural items that are being held at institutions like statehouses or museums. According to Hudson, "The problem is the act leaves the burden of proof on the Indigenous communities to demonstrate that they are descended from wherever or whoever those remains came from."
Anastasiia Pustovoit and Vitalii Polubinskyi.
Using GC to help with this sort of forensic investigation helps fill in some of the gaps in Maine's historical record, one centimeter at a time. "By doing this centimeter-by-centimeter resolution and overlapping that with the age depth model, we can say—and be fairly certain—that there were people here in this particular watershed from 13,000 to 500 years ago, or whatever it is. In some cases, we see continuous occupation over time and sometimes we don't. The one really disturbing thing we always see—and we've done this for five or six lakes at this point—is a pretty continuous signal of people in a watershed area for thousands of years, but across the board, no matter in the variance of time frame, we see the signal disappear 500 years ago." Five hundred years ago is about the time of post-European-contact population decline. What these results are showing us is the decline in Indigenous populations, due to disease or forced removal, and then a period of stasis before the population begins to increase with European colonization.
Hudson muses about teaching in a (really) small liberal arts college in Maine and how he would send students to other labs to visit and collaborate with scientists in Japan or Canada. He never considered that students and postdocs would want to visit his lab, but that all changed in 2021 when Hudson, Ruvan de Graaf MPhil ’22, and Mari Strandoo Rodin ’20 wrote a paper on the origin of life at deep sea hydrothermal vents that got a lot of notice in the chemistry world. Since then, Hudson has had a steady stream of interested postdocs wanting to come and work in his lab. This is not a bad thing, but Hudson is quick to tell these eager young scientists that COA is a small undergraduate institution where we focus on teaching and experiential learning... At COA the students come first. "After giving that pitch to Thiago Altair, he decided that this was the place he wanted to be. He was in the last year of his PhD in Brazil, and he came to COA on a grant through the São Paulo Science Foundation. Altair was doing research, but he and I also taught an electrochemistry class. He is an electrochemist by training, and he has a lot more expertise than I do in that field, which made for a really dynamic learning experience for the students." Giving students the experience of studying with a versatile bunch of young scientists from around the world gave Hudson the idea to apply to the Maine INBRE [IDeA Network of Biomedical Research Excellence] for funding to see if he could bring in Altair as a postdoc.
"The INBRE funding we received allowed us to have postdocs, fund students for doing summer research projects, and fund equipment and supplies." According to Hudson, “INBRE is invaluable for us to do what we do." Altair was the first to come to COA, then Hudson brought in Kheireddine, Pustovoit, and Polubinskyi. "They are all doing different things and contributing in different ways. Whatever we need, sometimes that is more teaching focused and others that is co-supervising student research projects. They've been amazing resources to have on campus."
Thiago Althair.
Which brings up the question of what now? for displaced postdocs from warzones who have spread across the globe to survive and continue their work. This question keeps Hudson up at night. He spent a good deal of his sabbatical in the fall of 2024 looking for other grants to support these postdocs staying put for another year or two. "I was able to get a mid-range grant of $50,000 from Maine Space Grant Consortium, but when you're talking about supporting three people, that's only a handful of months. We've got a NASA EPSCoR [Established Program to Stimulate Competitive Research] grant proposal we are waiting to hear on, and another from NASA MOAiCS [Multidisciplinary drifting Observatory for the Study of Arctic Climate] we are waiting on too, as well as another from the Maine Sea Grant. Any of these would fund the postdocs for several years, which would mean everyone [students, displaced postdocs, the MDI community] is a winner... But nothing is guaranteed." Hudson also has grants out to fund student research in the summer.
The reciprocal nature of science research and learning means it's not a solitary endeavor but an interaction between labs, funding sources, and the world around us. "We've got some irons in the fire," Hudson muses. “A lot of exciting things in the works." Exciting indeed. Here's to hoping the funding comes through.
