Grad student Wyatt Larrinaga explores how proteins bind to radioactive elements for fellowship at LLNL

As a fifth-year graduate student at the Pennsylvania State University, Wyatt Larrinaga investigates how proteins can be used to separate lanthanides. These elements, plus two others, make up the rare earth elements that are critical for technology, defense and a robust domestic energy supply.

But somewhere along the way, Larrinaga grew interested in branching out. Or, rather, moving down on the periodic table. He wanted to look closer at how these same proteins might bind to and separate actinides — heavier, radioactive elements.

“Separating actinides from each other is a big problem in terms of nuclear waste remediation, but the actinides are radioactive, so they aren’t something that I can work with at Penn State,” said Larrinaga.

Luckily, there was a solution: the Department of Energy Office of Science Graduate Student Research (SCGSR) program. This fellowship opportunity brought Larrinaga to LLNL for four months at the beginning of 2026 to work with staff scientist Gauthier Deblonde.

“I’ve been wanting to do this basically since I started grad school,” said Larrinaga.

At LLNL, Larrinaga examines how different protein characteristics affect binding of both lanthanides and actinides, including some of the rarest like americium and curium.

“For example, I’m comparing one of our newly discovered proteins with something that we've looked at previously and seeing what aspects of this protein either help enhance or decrease the actinide affinity,” he said.

Compared to current industrial methods for lanthanide and actinide separation, the protein-based method avoids strong acids and toxic organic chemicals that can produce environmentally harmful waste.

“The overall idea is to get similar industrial-scale separations, but with a completely aqueous, bio-inspired system,” said Larrinaga.

Interestingly, the proteins that separate lanthanides are naturally even better at binding certain actinides. Larrinaga and the team are experimenting with solution properties like pH and synergistic molecules that can improve the process even further.

As his fellowship concludes, Larrinaga will come out of it with publications in progress. The papers will cover how various elements bind to proteins and compare lanthanide and actinide affinity across different solution properties.

But for Larrinaga, perhaps the most valuable aspect of his time at LLNL was figuring out what to do next.

“A big part of this fellowship was understanding what it's like to work at a national lab, because it's not anything that we're exposed to in grad school,” he said. “I've loved it here so far.”