A Rutgers team now has $1.5 million to use in studying optical tweezing: a Noble Prize winning technique in studying how the cell walls of plants are created.
Professor Sang-Hyuk Lee of the Department of Physics and Astronomy, and his team, recently received the $1.5 million grant from the Department of Energy.
Before optical tweezers, scientists were not able to “trap” micron-sized particles because they were too small to be grabbed mechanically, Lee said. To put a micron in perspective, the average width of a strand of human hair is approximately 100 microns.
But, optical tweezers use light to grab particles, Lee said. Using a highly focused laser beam to provide an attractive or repulsive force, optical tweezers are able to trap these small particles and move them around.
“It gives you a very powerful tool to manipulate the microscopic world as you want,” he said. “Rather than just observing passably what’s happening, you can actively engage in controlling the process.”
As a biophysicist, Lee hopes to utilize this technique to study the process of exactly how plants’ cell walls are created.
While plant biologists know the main components of cell walls and the proteins that help to construct them, it is still a mystery how these cell walls are made in the first place, he said.
“If you take a biology course or read a biology textbook, all it says is that it happens out of nowhere,” he said. “Biophysicists are especially interested in the mechanism.”
In the past, Lee said scientists have used optical tweezing to determine very accurately the mechanics of molecules such as DNA and proteins.
Since these molecules are even smaller than the size of a micron, even optical tweezing is unable to trap them, so scientists use chemical bonds to attach the DNA or protein to the micron-sized bead. As a result, molecules the size of a few nanometers can be manipulated in an indirect way, Lee said.
He first used the optical tweezing technique for statistical physics, which uses probability and statistics to solve physical problems. During his postdoctoral training, he started researching biophysics and found that the same technique could also be used for biological systems.
“That was really fascinating to me, that this very physical method can be used to study biology,” he said.
For his research, Lee is combining optical tweezing with another Nobel Prize winning technique called super-resolved fluorescence microscopy, which uses light to allow images of small particles to be seen at high resolution. He said using light to both control and visualize the biological phenomena was a very unique process that allowed him to receive the grant.
“The fact they awarded this idea is amazing because it means it’s something that people also think are important,” he said.
Lee said he believes scientific research is important because it affects daily life and everyday people, even those who are not scientists.
“We scientists are not a completely different species. We ask questions about the same phenomena that people are experiencing and try to understand it,” he said.