When Dr. Whitney Stoppel isn’t working as an assistant professor in the Department of Chemical Engineering, she loves spending her free time outdoors and tending to her garden. During these moments, she reflects on the intriguing connections between healthcare, medicine, and the natural world, particularly plants and insects. As a result, she has studied the silk materials that come from the cocoons of silkworms. Her recent focus has shifted to studying silk materials, specifically those produced by silkworms. And now she has narrowed her research on an agricultural pest, the pantry moth, aka Indian meal moth or Plodia interpunctella. These tiny, winged creatures are known for creating silk sheets to cover the contents of pantry containers, like the one you had planned to use for dinner tonight.  

Collaborating with the Florida Museum of Natural History and partnering with the McGuire Center for Lepidoptera and Biodiversity, Dr. Stoppel and her team of engineering Ph.D. students were able to collect cocoons and silk materials from a diverse range of insects, some from unconventional sources like within a grain silo, or even each other’s own pantry. The team then studied the mechanical properties of the sheets of silk they gathered, with a focus on exploring the potential applications, such as creating biomaterials or innovative drug delivery devices.  

The first documented use of natural materials in medicine dates to ancient civilizations. The Mayans used mother-of-pearl for dental implants, while linen found its place in early Egyptian medicine as sutures. Similarly, the Greeks and Romans turned to spider webs as wound dressings, according to a study at the University of Bayreuth, Germany. 

“What’s great about these materials is that they’re very strong and tough, but they’re natural materials, so they’re easily degradable and your body has a ‘non-negative response’ upon implantation, as opposed to plastics,” explains Dr. Stoppel.  

When thinking about the potential of these silk fibers, researchers at the Stoppel Lab prioritize the well-being of patients and what surgeons and clinicians need in their work. Silk-based polymeric nanomaterials have emerged as a central focus in drug delivery research, thanks to their simple synthesis, tunable characteristics, and responsiveness to stimuli. Currently, Mari Pacheco, a Ph.D. candidate in the Stoppel lab leads a project toward developing an artificial oxygen carrier where they utilize purified silk protein to stabilize hemoglobin within nanoparticle materials to improve tissue oxygenation following an injury or disease. 

Lauren Eccles, a Ph.D. student on the team has been working on Plodia’s silk material characterization such as testing its thermal stability and mechanical properties since Fall 2022. She said that while documenting and handling many of these delicate materials can be daunting, the flexibility and broad range of fields the training and experience brings is what makes them a highly marketable recruit later. She adds that the collaborative work between engineering and entomology groups has further added to her communication and mentorship skills. 

“I think one of the best parts of watching them grow is seeing the shift in their competence as a scientist and a researcher, and their ability to run an experiment and then be able to judge their data and make a decision about what to do next on their own,” Dr. Stoppel said. Dr. Stoppel feels that at the same time, one of the most important skills students can learn is communication. “Being able to communicate your scientific findings at a high level, but then also being able to break down those scientific findings, to engage the other people in the room to come to solutions when problems exist is critical,” she stressed.  

Another Ph.D. student, Bryce Shirk who was working on his master’s degree in Entomology and Nematology as a research assistant at the McGuire Center, helped establish the population of a Plodia colony at the Stoppel Lab. Upon joining the lab in the spring of 2021, he expanded the colony and studied environmental factors that influence silk production – resulting in an accepted publication. With Lauren’s help, he is now focusing on genetic modification strategies using CRISPR to create novel silk-like proteins. It is these advancements in modifying native silk fibers into advanced fibers that hold the key to addressing contemporary and future healthcare challenges.  

Bryce feels that his experiences at the lab have helped him “appreciate how we as engineers can take the architecture that nature has evolved and apply it to solve various challenges.” Dr. Stoppel’s environment encourages them to utilize their creativity as they problem-solve, he adds. Additionally, her emphasis on communication has “significantly contributed” to his growth as a researcher. He is now considering starting a company that would apply the novel processes and technologies they have developed. 

Although the ingredients in tonight’s silk-covered container won’t likely find their way into Dr. Stoppel and her team’s dinner plans, their scientific advancements and innovative ideas are poised to transform pesky pantry moths into the unsung heroes of healthcare. Keep an eye out for the latest updates from the Stoppel Lab – there’s more buzz to come! 

You can view Dr. Stoppel’s playlist on our YouTube Channel.

By: Ada Lang, ChemE Marketing & Communications Specialist