College of Engineering News • Iowa State University

Bratlie’s first Iowa State adventure: biomedical engineering

Kaitlin Bratlie

Pursuing a desire to do something unconventional, Kaitlin Bratlie, assistant professor of materials science and engineering and chemical and biological engineering, is eager to take on the challenges facing the biomedical world.

“I like the biomedical field because it seems to have a lot of room for improvement and open questions I can work to answer,” says Bratlie.

The field also combines two of her research interests under one overarching goal. As a graduate student at the University of California-Berkeley, she worked with metal surfaces and found she enjoyed the research and interactions of surface science. She then made the switch to biomedical research as a postdoctoral fellow at the Massachusetts Institute of Technology (MIT). The transition from metals to biomedicine was not a simple or immediate one.

“There was a big learning curve,” says Bratlie. “I was there for three years, which was nearly enough time to get a second PhD.”

Her research team at MIT worked to reverse type 1 diabetes by using pig pancreas cells in humans whose own pancreases did not function. However, the porcine cells were often rejected in lab tests. To combat the problem, the foreign cells were encapsulated with polymers to trick the body into accepting them. Bratlie was responsible for analyzing the biocompatibility of 1,000 different polymers to see which ones could be used to encase the cells.

Now in her own lab, Bratlie plans to focus on what makes biomaterial, like heart valve and hip replacements, compatible in living things. The outcome of this work will include a list that details which biomaterials function best in living things and which ones are rejected. These findings will be used to engineer more compatible and effective biomaterials.

To conduct her research, she will look at polymers in a more detailed way than she did during her project at MIT, using three different methods. By using imaging of biomaterials in live tissue, Bratlie will create a better molecular level understanding of tissue responses to foreign bodies. She will also look at complement activation, a reaction that can happen when blood or tissue comes in contact with foreign materials and that often causes a rejection of that material. To round out the study, she will explore enzyme reactions on the surface of the implanted biomaterials.

“When deciding what to focus on, I really had to dig in and find the holes in previous research to see what could be done next,” says Bratlie. “I was familiar with a good portion of literature, but I spent a lot of time reading and brainstorming before deciding what I wanted to do.”

A native Minnesotan, Bratlie is glad to be back in the Midwest to start her experimentation.

“Iowa State has a great engineering program and is a great school overall,” says Bratlie. “There are so many resources, equipment, and bright students here. I’m confident it’s the right place for me.”