On Wednesday, Jan. 31, it was released that UCR bioengineering Professor Valentine Vullev received a grant from Fulbright, an American scholarship program, to conduct research on charge transfer at the Brazilian University of Sao Paulo for the 2018-19 academic year. Charge transfer refers to the movement of electric charge between molecules, such as when electrons move along a wire to generate electricity. The goal of this research is to improve understanding of Vullev’s own “bioinspired molecular electrets” and to apply new findings to charge transfer.
An electret is an artificial magnet, created when an electric charge is contained within an insulating material. Historically, electrets only hold charges, not transferring them, but Vullev has broken ground by engineering his own “bioinspired” electret, which defies that inheritance and allows charges to pass in and out through openings in the surface. But they are still not conductors, and are more like a molecular capacitor, as Vullev notes. “If I put a charge in something that is an insulator, and that charge has sites to move along, it’s not really a conductor, per se, it doesn’t necessarily have to have a lot of free charge carriers. I know it’s a little confusing,” says Vullev.
Vullev thought of the idea after observing biological cell activity. A cell’s membrane is an insulator, but body cells use the charge of ions in the bloodstream and the cytoplasm to create pulses that control our movement, thinking and inner body functions. Ions enter and leave the cells through proteins on the cell membrane known as ion channels, and upon entering or leaving, the cell membrane retains charges. These observations are what led to Vullev’s creation.
“All the things (biological cell structures) are insulators, and still, biology shows a lot of examples of long range charge transfer,” Vullev comments. “We know that life exists because those processes occur, so borrowing this idea, you can go around what the physics prevents us to do.”
Vullev is confident that his research on electrets, and other related research, will find its way into widespread use. “If you establish fundamental principles, you can take them to new fields,” says Vullev. “Even start new fields of science and engineering, and that’s the whole idea of academic research: it’s to change the way people think about things. If the research doesn’t do that, that means that you’re just improving things, but you’re not really pushing the limits.”
Ultimately, Vullev does not only aim for his research to improve current scientific creations, such as solar power cells and other energy conversion methods, but for the results to be applied in many different areas. But Vullev observes that research into his electrets is very young, having only begun with a theoretical paper posted in 2009, and makes a point that finding applications can be difficult.
“We are looking at things to bring an understanding of energy conversion and from there, hopefully, applications,” says Vullev. “But the ideas are so new that they don’t have exact applications. It takes time to mature and do testing and so forth.”
Vullev’s new research intends to find such “exact applications” and his research’s second goal is to expand the application of his electrets to cell biology. He notes that the electrets he observed were photo-driven; this means that light could be used to “push” charges in and out of the electrets. As such, cells could be manipulated in the same way, suggesting that cell function can be medically maintained.
This can be useful for treating many conditions, like arrhythmia, which comes from excessive potassium, or hypertension, which comes from excessive sodium. “A photoinduced charge transfer (can occur with the electrets),” states Vullev, “so if you can use those to move charges across cell membranes, then you can actually control it (the charge within the cell).”