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Nolan Petrich, a chemical engineering PhD student, has received a 2025 National Science Foundation Graduate Research Fellowship, a prestigious award that recognizes and supports outstanding students in a wide variety of science-related disciplines. Petrich is advised by Distinguished Professor��Kristi Anseth.

This year, the National Science Foundation awarded Graduate Research Fellowships to 11 91��Ƭ������AV College of Engineering and Applied Science students. Due to federal budget cuts, the program was reduced by 25 percent, with 1,500 fellowships awarded nationwide compared to 2,000 last year.��

Fellows receive a three-year annual stipend of $37,000 and full coverage of tuition, fees��and insurance, along with opportunities for international research and professional development that span five years.

What is your research focused on?

I’ve seen firsthand how intestinal diseases can affect quality of life—my mom and youngest brother both live with Celiac disease. While my research doesn’t focus on Celiac directly, it’s driven by a broader motivation to understand how the intestine works, heals and malfunctions in disease.

The human intestine relies on a single layer of cells that carry out digestion, absorb nutrients and defend against harmful microbes. Since these cells are constantly exposed to physical and chemical stresses, such as compression and stretching as food moves through the digestive tract, they must be renewed regularly to keep the intestine functioning properly. This renewal process is driven by intestinal stem cells, which live in valleys within a repeating “peak and valley” architecture along the tissue surface.

Figure 1

In the Anseth lab, we can recreate this complex multi-cellular structure by growing miniature lab-grown versions of the intestine—called organoids—in soft, water-rich materials called hydrogels, a substance similar to Jell-O. The Anseth lab designs special phototunable hydrogels that change their properties when exposed to light, giving us the ability to control the environment around the organoids in both space and time.

Previous work in our group has shown that softening the hydrogel around organoids can trigger them to develop budding structures that resemble the natural intestinal architecture, including the emergence of different cell types. My research explores how these changes in the material environment influence stem cell behavior, with a focus on different proteins in the cell responsible for determining what type of cell a stem cell becomes. However, it is unknown how these various proteins dictate cell fates over time.

To study this, I use light-sheet microscopy, a cutting-edge 3D imaging technique, to visualize where these proteins are located in the cells of the organoid over time. I then relate this to the changes visualized in the tissue structure. For example, Figure 1 shows a cross-shaped organoid patterned with light, where a protein (magenta) and the cell nuclei (white) can be seen. Figure 2 shows a 3D rendering of cell nuclei in part of an organoid, color-coded by depth. Control over our hydrogels combined with images like these help us uncover how the physical environment influences signaling proteins that send and receive signals to control processes like growth, healing and immune responses.�� It also helps us monitor the resulting stem cell fates and tissue development—knowledge that could one day lead to better treatments for intestinal diseases.

What are potential applications of your work?

Figure 2

First, intestinal organoids can be powerful tools for studying diseases and testing new drugs. However, they currently grow with a lot of variability. By using phototunable hydrogels, we can control the shape, size and structure of organoids with greater precision, which is crucial for using organoids in drug testing and could eventually help in the manufacturing of functional intestinal tissue for transplant therapies.

Second, my research provides insight into how abnormal intestinal growth occurs in diseases like inflammatory bowel disease (IBD) and cancer. Too much activity of signaling proteins has been linked to uncontrolled growth in cancers and irregular tissue structures in IBD. By understanding how signaling proteins function in healthy tissue development, we can identify what goes wrong in disease—and potentially find new targets for therapies that prevent or treat these conditions.

In short, this work could help develop more reliable tools for research and drug screening and contribute to the future of personalized medicine, healthcare that uses a person’s unique genetic, environmental and lifestyle information to tailor treatments and prevention strategies specifically for them, as well as regenerative therapies that help repair or replace damaged tissues or organs by using the body’s own healing abilities for intestinal diseases.

What does receiving this award mean to you?

Receiving this award is an incredible honor. I’m deeply grateful that the National Science Foundation saw value in my work and chose to support it, especially in such a competitive year. I want to thank my advisor, Dr. Kristi Anseth, for her outstanding mentorship and her enthusiasm for asking bold scientific questions. I’m also grateful to my previous mentor at the University of Delaware, Dr. Christopher Kloxin, who completed a postdoc at CU Boulder and was the one who first introduced me to research and encouraged me to pursue my PhD here.

This fellowship provides me with the freedom to pursue new ideas and take creative risks in my research. I plan to use the funds to continue investigating how specific proteins guide stem cell fate and intestinal development. I also aim to expand this work by incorporating biochemical signaling into our phototunable hydrogel system—a direction that has not yet been explored in this context. By combining mechanical and biochemical cues, I hope to build a more complete understanding of how the cellular environment shapes intestinal tissue formation and regeneration.

I’m thankful for the mentorship and support I’ve received throughout my research journey—from postdocs and graduate students to peers and colleagues during my undergraduate years. I wouldn’t have received this award without the guidance of my mentors and the encouragement of my family and friends.

Beyond the lab, I’m excited to use this fellowship as a platform to mentor others and help students discover their passion for STEM research throughout my graduate education.

Read more about CU Boulder's 2025 National Science Foundation Graduate Research Fellowships.