The study of electrostatic properties of peptoid nanosheets

Robert Accolla

Robert Accolla holds a glass slide coated with a thin layer of gold that he uses to study the electrostatic properties of peptoid nanosheets. The gold will act as a conductor and interact with various liquid samples as Accolla performs electrophoresis experiments on peptoid nanosheets, a synthetic material that imitates nature’s protein-forming peptides and can be used in applications ranging from molecular sensors to artificial enzymes. (Photo courtesy of Ronald Zuckermann from Lawrence Berkeley National Laboratory).

Studying nanotechnology may not sound like the typical “how I spent my summer” story, but for Robert Accolla, he enthusiastically recalls his summer studying the electrostatic properties of peptoid nanosheets at the Molecular Foundry at Lawrence Berkeley National Laboratory.

A junior from Virginia Tech, majoring in biological systems engineering, Accolla researched peptoid nanosheets as part of an overall field that is exploring how this synthetic nanomaterial can be used more broadly in drug discovery, diagnostics, and drug delivery.

Accolla researched peptoid nanosheets as a participant in the U.S. Department of Homeland Security (DHS) HS-STEM Summer Internship Program. This program provides undergraduate students majoring in homeland security related science, technology, engineering and mathematics (HS-STEM) disciplines the opportunity to conduct research in a DHS area at federal research facilities across the U.S.

“Much of my research was still in the discovery phase,” said Accolla. “This research is so important because most of it has to do with using peptoid nanosheets to manipulate biology to aid in some biological process.”

Peptoid nanosheets are created when peptoids, which are microscopic, bioinspired polymers, clump together to form a two-molecule thick sheet. These sheets can be used as building blocks to create more complex structures that can be used as the foundation for other scientific research. During his internship in the lab of Dr. Ronald Zuckermann, Accolla researched the physical and electrical properties of peptoid nanosheets.

Specifically, he studied whether charge was a dependable way to allow the peptoid nanosheets to self-assemble into layers. His two main tasks were observing charged peptoid nanosheets and investigating how peptoids reacted in a charged solution.

“Peptoids provide a material capable of interacting in a biological way without some of the current limitations seen with peptides, which is why this research is so important,” said Accolla. “While peptoids are close enough to peptides in that they are biocompatible and can be modified like peptides, they are not broken down in the body in the same way peptides are, and they have a larger variety of side groups that can be used in synthesis.”

According to Accolla, peptoid nanosheets have high level of ionic charge, but are overall neutral. “Through these experiments, we found it was possible to exploit slight imbalances in overall charge, and use electrophoresis to move the nanosheets through the solution. This could serve as the basis for a new nano-manufacturing method.”

This opportunity helped Accolla confirm both his interest in biomedical engineering and his future plans. “I knew that I wanted to work in a field similar to the one that I did research in over the summer, and this experience confirmed that for me. It also gave me the opportunity to know what I must do to attain such a position once I graduate.”

Overall, Accolla recommends this program to anyone searching for a high-quality internship. “It took me out of my comfort zone in a controlled way and allowed me to really apply all the knowledge that I had been storing up over my first two years of college.”

After completing undergraduate, he plans to apply for the biomedical engineering master’s program at Virginia Tech. Ultimately, he wants to either get a doctorate or go into industry.

The DHS HS-STEM Summer Internship Program is funded by DHS and administered through the U.S. Department of Energy’s Oak Ridge Institute for Science and Education (ORISE). ORISE is managed for DOE by ORAU.