Chemical Engineering Professor Receives Prestigious CAREER Award

Cells are the basic unit of life. But an individual cell contains compartments, each with different chemical environments necessary for proteins to carry out their jobs.

Karthik Nayani, an assistant professor of chemical engineering, received a five-year, $500,000 National Science Foundation CAREER award to unravel how rod-shaped strands of DNA move particles within cells to create these compartments.

"The CAREER award gives me an amazing opportunity to do some fundamental science that will unravel the mysteries behind liquid-liquid phase separation caused by rod-shaped particles. I am extremely excited about this project and am happy that the scientific community finds this important problem highly relevant," Nayani said.

Nayani's research to understand how DNA works within a cell could lead to faster and more sensitive tests for infectious diseases or abnormal genes.

The prestigious CAREER grants support early-career faculty with the "potential to serve as academic role models in research and education," according to the NSF.

"I am thrilled that Karthik has received an NSF CAREER award," said Keisha Walters, chair of the Ralph E. Martin Department of Chemical Engineering. "Not only does this award support the research success of talented junior faculty, like Karthik, it also advances cutting-edge science and engineering efforts in our state and helps prepare our students for career success."

LOOKING INSIDE A CELL 

Imagine each cell is like a restaurant dining room about to host a banquet, Nayani said. To make room for the many guests, the tables and chairs must be moved against the walls. In a cell, large particles are pushed together to make room for smaller particles to move about, a process in chemistry called depletion. Rod-shaped particles like DNA are particularly strong depletion forces.

"DNA could be responsible for a lot of the physiological processes happening in the body," Nayani said.

Scientists do not fully understand why rod-shaped particles are so strong. Nayani hopes to answer that fundamental question with work supported by his CAREER Award. In fact, most previous research has focused on spherical particles in cells, because those shapes are easier to model mathematically.

DNA's tendency to arrange particles within cells can also be used to detect the presence of a particular type of DNA. Nayani can introduce disk-shaped particles into the cell. To make room, the DNA will stack the disks, creating a rod-like shape, like the way dozens of stacked pancakes would eventually form a column. The rod-shape becomes a liquid crystal, which can be detected optically.

Current PCR tests to detect DNA, like those that are widely used to confirm COVID-19 infections, often take days to deliver results. This new process proposed by Nayani would be almost instantaneous and could identify small amounts of a particular strand of DNA. The presence of DNA could even be monitored live, which could be used to detect harmful biofilms as they form.

A WAY TO UNDERSTAND THE WORLD 

Nayani's research covers a wide range of subjects. He studies the fundamental structures of cells and the role of DNA. He created a new way to detect COVID-19 and other infectious diseases using liquid crystals. He is developing a technology, funded by an Arkansas Research Alliance grant, to make lithium extraction in southern Arkansas more efficient.

The research interests all fall within the field of "soft matter physics."

"It all comes down to understanding the underlying physics of how things work that are soft and squishy, and not metals," he said.

Soft matter, neither a solid nor a liquid, can be deformed and reshaped by heat and force.

As part of his CAREER award, Nayani will create programs for K-12 students to show them how soft matter and chemical engineering can help them understand the world around them.

"Why do we have to wash our hands to kill the coronavirus? How to make a good espresso? Those things are both chemical engineering concepts," Nayani said.

Chemical engineering graduates can also work in a wide range of areas, like the oil industry, manufacturing, the growing field of lithium extraction or molecular research.

"I think that appeals to high school students because they won't get siloed. If they don't like something, there's avenues open to go into a different field with the training they have," he said.