By Emily VanGerpen ’15 B.S.
To solve any problem, you need the right tools. When you have a flat tire, you replace it with a spare. If you break your arm, you need a cast and probably medicine for the pain. But what about problems like viruses or inefficient living cells—problems that are too small to see?
You need those same everyday tools, but on a much smaller scale. You need nanotechnology. “Our research [at USD] is focused on the design of particles that act like little tools, such as tweezers, paintbrushes or knives,” said Grigoriy Sereda, Ph.D., a professor in the Department of Chemistry at the University of South Dakota. “These tools help people in various areas of science solve real-life problems.”
That’s essentially what nanotechnology is: the study and design of extremely small particles that are then applied across all other science fields. What’s hard to conceptualize is just how small these particles are.
The International System of Units, or SI, defines a nanometer—the size of a nanoparticle—as one billionth of a meter, or 10-9 meters. For a more visual comparison, imagine the diameter of a marble as being one nanometer. The diameter of Earth, then, would be one meter.
Their miniscule size makes nanoparticles incredibly versatile. At USD, Sereda collaborates with experts in areas like immunology, biology and materials science to help solve problems. He credits his background in organic chemistry for the unique ability to design, make and manipulate the different particles that further his team’s and others’ research.
“Organic chemistry is a bridge between theoretical science, real-life applications and art,” said Sereda. He received his Ph.D. in organic chemistry from Moscow State University in 1992 and has been working with nanotechnology since his first sabbatical in 2011. Six months in a nanotechnology laboratory at the University of Victoria, Canada, exposed Sereda to the skills and experience that allowed him to launch his own nanoparticle research upon return to USD.
But the professor originally had no intention of working with nanotech.
“I did, however, have a hunch that the power of organic chemistry could reveal itself in rather unexpected ways,” he said. That power has since impacted lives on campus and nationwide. Sereda has a passion for giving others the tools they need to succeed, as evidenced by his ongoing research contributions in various departments.
The human immune system is always working by fighting off microbes, or germs, that have gotten through. Immunologists study these defensive processes to better understand how they function and in what ways they could be improved. The results of their work, amongst other discoveries, are the therapies and vaccines that help everyone from sick patients to the general public.
As it relates to nanotechnology, immunology takes place on a very small and complex playing field. The bacteria that cause health problems are living organisms, making them difficult to study or manipulate. Therefore, to create a solution, scientists need a nonliving tool that they can control.
“Nanoparticles must be able to sense the body’s response to a vaccine and thus help evaluate the vaccine’s quality,” said Sereda. He works with Victor Huber, Ph.D., to do exactly that.
Huber is an associate professor in Basic Biomedical Sciences at USD and has been collaborating with Sereda for more than seven years. Huber works primarily in immunology and immune responses as they relate to vaccines.
“Bacteria don’t want to be bound to the antibodies that are prompted by vaccines,” he said, “but nanoparticles don’t care. So Sereda and his team can design particles that act the way we want them to, bind to different surfaces, and help us study specifically what we need.”
This freedom of design impacts not only present studies, but also those in the future. Once it functions as needed, a particle’s design can be replicated so it works the same way for different issues.
“Nanoparticles give us a consistent tool we can use to measure immunity against other viruses and bacteria,” said Huber. Take the recent coronavirus, for example, which can mutate and affect people differently. With this technology, Huber and his team can better understand the different vaccination requirements for a virus with multiple variants.
Sereda defines his role in the research as one of making humble contributions to those who might benefit from his work. In a world with many big problems to solve, that population includes just about everyone.
The study of life offers plentiful applications for nanotechnology. Problems can occur in everything from individual cell functions to global food supply, so the need for solutions is urgent—and growing.
Sereda is helping meet that need with nanotechnology “tools” that deliver specific drugs and genetic materials where and when it’s most beneficial. His contributions have helped facilitate a number of significant discoveries.
Khosrow Rezvani, Ph.D., is an associate professor for the Division of Basic Biomedical Sciences at USD. He and a team of researchers recently invented a new technology that will treat patients diagnosed with an advanced stage of colorectal cancer (CRC).
“Despite advances in treatment regimens, one third of CRC patients will ultimately die from metastatic disease. The prognosis for patients with metastatic disease is an abysmal 12% or less with no significant improvements in the last 10 years,” Rezvani said. “Thus, there is an urgent need for new therapies for patients with metastatic CRC.”
Their solution was to create a tumorsuppressing drug, as well as enable its delivery directly to the tumor site. USD is the first to successfully accomplish both of those goals—an achievement made possible by a collaboration between Rezvani and Sereda.
Rezvani and his team created this novel drug with veratridine, a natural compound isolated from a plant extract. While suppressing metastatic cancer, veratridine is unfortunately neurotoxic. Using site-directed nanoparticle technology, Sereda designed a particle that releases their anti-cancer drug precisely at the location of cancer cells. This process circumvents the unwanted toxicity of veratridine and keeps it away from the brain.
“The selective drug delivery and release will drastically reduce the drug dose required for treatment and exposure of non-cancerous tissues and neurons to the drug,” said Sereda. “This will play to the strengths of Rezvani’s research and facilitate bringing the product to the patients. Ultimately, it will bring the drug to patients faster.”
Among other implications, more efficient medicines are a dramatic step toward better patient outcomes. And, although there is yet more work to be done, Sereda appreciates any opportunity to continue making the world a better place.
In the Department of Biology at USD, Bernard Wone, Ph.D., studies plant genetic engineering and its role in improving the quality, productivity and environmental stress resilience of crop plants. Together, he and his research group have made significant contributions to the field of plant biotechnology.
One of their recent studies involved using nanoparticles for genetic transformation. Currently there exists a gap between successful plant genome editing and an efficient, environmentally friendly method of transformation. Wone and his team sought to bridge that gap with the help of nanotechnology.
They needed a particle that could alter a plant’s DNA without causing a toxic reaction inside the plant cell. So, they went to Sereda.
“In this kind of situation, a particle needs to bind a genetic material, bring it inside a plant’s cell, tweak its biology and disappear to avoid causing harm to the environment,” said Sereda.
Using Wone’s specifications, Sereda’s lab team created a particle that helped reach Wone’s research goals: safe, efficient plant gene transformation
“Our method will not only aid in deciphering and directly testing gene function in a variety of plant species, but will facilitate the enhancement of crop productivity via genome manipulation,” said Wone. “Increasing crop productivity is essential to meet the growing food and energy demands of a burgeoning human population under increasingly stressful environmental conditions.”
Granted, problems like cancer and food scarcity have no easy solution. Any issue that affects an entire population is inevitably too big for one person to solve—no matter what tools they’re using. But as the research conducted at USD continues to show, nobody is solving these problems alone.
A Culture of Collaboration
As is common in the research community, Sereda’s work has been influenced by the professionals with whom he works. It happened first with nanotechnology and, more recently, with a branch of the field known as microfluidics.
In 2019 he spent his sabbatical in Portland, Oregon, and worked alongside prominent dentist Luiz Bertassoni. Their time together inspired Sereda’s interest in microfluidics: the study of the behavior, precise control and manipulation of fluids that are geometrically constrained to a small scale.
“Working with Dr. Bertassoni took my dentistry research to a new level and made microfluidics a central piece of my current research,” said Sereda. He helped with a few experiments related to the innovative device, “tooth-on-a-chip,” that was invented in the research group of Bertassoni. The device is aimed to function like a tooth does inside the mouth.
However, since it’s a nonliving device, researchers can more easily study and control the “tooth’s” behavior without any ethical restrictions of a human clinical study. Once back at USD, Sereda began applying that experience to his own work. He’s currently developing a new generation of toothpastes and dental flosses that can address tooth pain, hypersensitivity and infections.
Sereda refers to the university’s research community as an amazing, collegial and supportive environment that allows its professionals to successfully tackle challenges together.
“The relentless collective efforts by everyone here for building the instrumentation and human research infrastructure, and sharing it with other faculty, is absolutely paramount for bringing a research idea to a fundable project,” he said. Since lack of funding can hinder project completion, the ability to create and share resources without user fees is critical.
Equally vital to that infrastructure are the classrooms where these researchers explore even more through teaching. Education is not only a platform for sharing the knowledge of each field, but also a community where students can learn and get involved. Seeing firsthand the work being done on campus inspires graduate and undergraduate students to become part of the process.
In fact, graduate students do almost all the experimental work—an especially valuable resource that benefits everyone involved.
“I’ve learned so much about teamwork and patience in my research experience,” said Sajith Wijewardhane. “Discussions and collaboration with other departments teach us to trust each other if we expect the research to succeed.”
Wijewardhane is a graduate student in the Department of Chemistry and part of Sereda’s research team. He’s an aspiring researcher who, with Sereda’s help, was able to balance the demands of academic and lab work students often experience. The tools obtained in both areas have set him up for a successful professional career.
“Research and teaching are inseparable,” said Sereda. “Working with students in a research laboratory and in a classroom is our professional way to make the world a better place.”
And that’s no small task. Many problems need solving if the world is going to be a better place. But fueled by energy and passion for change, Sereda is determined to give students and colleagues the tools they need to succeed. After all, what is success if not individual parts working together to solve big problems?