Clemson graduates push ‘glow-in-the-dark’ paper to the cover of the journal Soft Matter

CLEMSON, S.C. – As part of the research work of undergraduate students majoring in chemistry, two Clemson graduates have developed groundbreaking work showing that laser engraving of paper can result in the formation of fluorescent compounds similar to those present on carbon dots, which are traditionally used in sensors and electronic applications. This is a breakthrough in the field, but only part of the successful story. The example set by these students might have the biggest impact on science.

In recent edition of Soft Matter, a journal of the Royal Society of Chemistry, a team formed by researchers at Clemson and the University of Sao Paulo published a manuscript titled “Fluorescent Patterning of Paper Through Laser Engraving.” They describe a fast, simple method to engrave patterns on paper, observable with UV light, that can be used to conveniently identify sodium hypochlorite (bleach), that is now serving a critical purpose.

“It’s basically a laser printer, but instead of the laser interacting with the ink prior to attaching it to the paper, we use an infrared laser to treat the paper itself,” said Garcia, a professor in the College of Science’s department of chemistry and a Fellow of the Royal Society of Chemistry. “It increases the temperature of the paper and that’s the reaction we use to make the fluorescent compounds. We then use the treated paper as a sensor for bleach. In the age of COVID-19, bleach is one of the simplest and cheapest sanitation solutions. But we are thinking of a number of potential applications, including marking money, marking cardboard packaging, or doing tracing.”

Kaylee Clark and Lauren Skrajewski are the principal authors on the paper. Both are now in graduate school, but they conducted their research while undergraduates in the department of chemistry.

“Kaylee was the first one who started working on the project, with Tomás Benavidez, who was a postdoc at the time,” Garcia said.

Clark gathered about 50 percent of the data and developed a way to make the paper fluorescent and to monitor and measure the fluorescence. The project was an opportunity for her to discover what she wanted to do – and to shift gears to make it happen. When Garcia told her to “figure out everything you can about it,” Clark devoted herself to crafting the work.

“A lot of it was me wandering around trying to figure out what he meant by that, but once I did, it was pretty cool,” Clark said. “I was able to plan and do a lot of the experiments by myself. It convinced or inspired me to do what I’m doing now. When I started working with Dr. Garcia, he asked me what I wanted to do with my future.”

Clark’s plan was to graduate from Clemson and get a job in industry – “no more school,” she said.

Instead, she is now at Colorado State University, where she just completed the third year of a Ph.D. program.

“Through working in his lab, I realized I really liked research, and the best opportunity to do that was to go on to graduate school,” she said.

One of the most critical aspects of Clark’s experience as an undergraduate engaged in research at Clemson was the freedom to take chances, make mistakes and grow through hands-on work.

“It really helped me learn to think on my own and think about what I’m doing and what the results mean,” she said.

Once Clark graduated, Lauren Skrajewski came on board. Her portion of the project included spending five weeks in Brazil to continue experiments in collaboration with a team at the University of São Paulo. The resulting paper is her first publication. She recently finished her first year of graduate school at Michigan State University, where she is working toward a Ph.D. in analytical chemistry while conducting research in the biomedical engineering of devices. She is currently working on the development of a new insulin pump/artificial pancreas device. She credits her undergraduate research for opening doors and giving her focus.

“I was able to work with Dr. Garcia to bounce around a few different projects to find what I liked the most,” Skrajewski said. “I was able to figure out what I wanted to do and where my passions were and what would give me the success to focus on my path.”

Garcia said he is extremely proud of his graduates. Beyond the current publication, he notes the success of recent graduate Laura McCann, who is starting graduate school at Texas A&M University. McCann said she chose Clemson because of the opportunity to conduct research as an undergraduate, but she actually started even earlier, joining the Experiences in Undergraduate Research, Exploration and Knowledge Advancement (EUREKA!) program for incoming honors students during the summer prior to her freshman year.

“I started working with Dr. Garcia that first summer,” McCann said. “I really loved research.”

McCann continued working in Garcia’s lab beginning with the first semester of her freshman year. Her opportunities continued with a research stint in Brazil, studying Spanish in Seville, participating in the 2019 Nuclear Chemistry Summer School in California, receiving the Warwick Chemical Foundation Award in Chemistry and receiving a prestigious Goldwater Scholarship. She is now attending graduate school through a National Science Foundation Fellowship. She applied to and was accepted by five graduate programs.

“It has been an amazing four years and I really do owe a lot of that to him,” McCann said.

But Garcia said he is the lucky one.

“I’ve had a lot of undergrads who are willing to work and choose a project,” he said. “We pair them with a senior member of the lab who is able to work with them, introduce them to the project and let them take ownership as they mature. I’m not doing anything special. They are working really hard and they are willing to put in the time and effort in the development of these projects.”

Funding is always needed to continue to advance both the science and the talent produced by his lab and others in the College of Science. Currently, Garcia is applying for grants to propel the fluorescent engraving research to its next steps. And he continues to recruit, equip and encourage his undergraduate students to go beyond the classroom. These partnerships produce results.

“Other than that, it’s luck,” Garcia said. “As a good friend of mine would say, ‘Luck is when opportunity meets capacity.’ In their case, some of the experiments didn’t work. But they keep trying until they get a breakthrough, and if they are able to chase it, they end up with a paper or more.”

In addition to Garcia, Clark and Skrajewski, other contributors to the paper are Tomás Benavidez, now at National University of Cordoba; Letícia Mendes, Erick Bastos, Thiago Paixão and Felipe Dörr of the University of São Paulo; and Rakesh Sachdeva and Amod Ogale of Clemson University.