John Groves
Photo by Brian Wilson
Tyler Groff
Photo by Denise Applewhite
Two Princeton University research projects — a new tool for visualizing drug therapy in the brain and a method for aiding the search for planets outside our solar system — have been selected to receive grants from Princeton's Eric and Wendy Schmidt Transformative Technology Fund.
The fund supports concepts with potential for broad impact in the natural sciences and engineering. It was created in 2009 through a $25 million endowment by Google executive chairman Eric Schmidt, a 1976 alumnus and former trustee, and his wife, Wendy, to encourage the development of new technologies that could transform entire fields of science.
The winning projects are a technology for attaching drug molecules to radioactive labels that enable detection of the drugs using brain imaging, led by Princeton chemistry professor John Groves; and a method for improving the image-correcting systems on telescopes to better detect far away objects including planets outside our solar system, led by Tyler Groff, Princeton postdoctoral researcher in mechanical and aerospace engineering.
"These are two truly innovative technologies that have tremendous potential to lead to breakthroughs in their areas of study and beyond," said A.J. Stewart Smith, dean for research, the Class of 1909 Professor of Physics, and chair of the committee that selected the winners. "The Schmidt fund has enabled Princeton University to make investments in ideas that have the potential to radically boost scientific and technical advancement."
New tools to visualize drug therapy in the brain
John Groves and his team will receive $600,000 from the fund to develop a system for labeling drugs with radioactive markers that make them visible using a brain-imaging method known as positron emission tomography (PET) scanning.
The rapid creation of these radiolabeled drugs could enable medical researchers to explore whether the experimental medicines are reaching their targets, and could aid in the development of drugs to treat disorders such as Alzheimer's disease and stroke, according to Groves, Princeton's Hugh Stott Taylor Chair of Chemistry.
The method for creating the radiolabeled drugs is based on a recent discovery in Groves' lab of a new process, published in Science last fall, for incorporating fluorine atoms into drug molecules. The process uses a synthetic liver enzyme to replace hydrogen with radioactive fluorine in the drug molecule. This new method avoids the toxic and corrosive agents in use for such processes today.
With the Schmidt funding, Groves and his team will develop an automated method to quickly attach radiolabeled fluorine to drug molecules. The major hurdle, Groves said, is finding a way to accelerate the chemical reaction between the fluorine and the drug so that the attachment can be completed before the compound degrades, which it does in about two hours. The group has already made substantial progress, Groves said.
"The Schmidt funding will enable us to explore ways to optimize the chemical reaction," Groves said, "as well as to create a prototype of an automated system that can carry out the reaction without the need for a human operator. This will allow us to create a rapid and noninvasive way to evaluate drug candidates and observe important metabolites within the human brain."
Aiding the search for planets
Inspired by the search for planets outside our solar system, Princeton postdoctoral researcher Tyler Groff conceived of a technology that could enhance the quality of images from telescopes. Groff will receive $300,000 in Schmidt funding to develop a new device for controlling the mirrors that telescopes use to correct blurring and distortion caused by atmospheric turbulence, heat and vibrations.
This technology, known as adaptive optics, involves measuring disturbances in the light coming into the telescope and making small deformations to the surface of a mirror in precise ways to correct the image.
These deformations are made using an array of mechanical devices, known as actuators, each of which can move a small area of the flexible reflective surface up and down. But existing actuators have limitations, such as requiring continuous power and being limited in the amount of correction they can provide. Additionally, the spaces between the actuators create dimples in the mirror, producing a visible pattern in the resulting images that astronomers call "quilting."
Groff envisioned replacing the array of rigidly attached actuators with flexible ones that can smoothly change shape as needed. Instead of actuators, attached to the back of the mirror is a packet containing iron particles suspended in a liquid, which is known as a ferrofluid. Just as iron filings can be moved by waving a magnet over them, applying varying magnetic fields to the ferrofluid creates changes in the shape of the fluid that in turn deforms the mirror.
The ferrofluid mirror enables high image quality while being more resistant to vibrations and potentially more power efficient, which will be important for future satellite-based telescopes, said Groff, who works in the laboratory of Jeremy Kasdin, professor of mechanical and aerospace engineering. Ferrofluid mirrors do not have the size limits of the high actuator-density mirrors in use today, so they have the potential to be more easily integrated into the telescope. A ferrofluid mirror can also achieve something that a rigid actuator mirror cannot: it can assume a concave or bowl-like shape that aids the focusing of the telescope on objects in space.
"A telescope that uses ferrofluid mirrors would be able to see dim objects better, greatly enhancing our ability to probe other solar systems," Groff said. "The Eric and Wendy Schmidt Transformative Technology Fund will enable the studies needed to develop this technology, which has the potential to greatly expand our ability to find new planets in the universe."