What if you could quickly tell from a drop of blood whether a patient had a bacterial infection? Or gauge how well his or her immune system was functioning? Rohit N. Karnik hopes his groundbreaking work on fluid flow will lead to a way to quickly discern important information about blood cells in real time. His insights could also result in cheaper and more effective ways to purify water and improve drug delivery within the body.
An associate professor of mechanical engineering, Karnik investigates the most fundamental nature of fluid transport: how cells navigate channels, how water flows through membranes, and how vapor molecules act when they encounter a liquid’s surface. His work on fluid flow at the micro- and nanoscales will be among the countless branches of research to benefit from MIT.nano, a new 200,000-square-foot building due to open on campus in 2018. It will house state-of-the-art equipment, teaching labs, imaging and prototyping facilities supporting research with nanoscale materials and processes, with potential impact in such areas as energy, health, life sciences, quantum sciences, electronics, and manufacturing.
Within the field of nanofluidics, Karnik designs solutions to widely varying problems and vastly different environments. Take blood analysis, which can be particularly challenging in developing countries where health care workers have limited or no access to expensive diagnostic lab equipment. His lab is creating a handheld device that can quickly and cheaply separate and analyze individual cells in a blood sample.
On another front, Karnik is developing ultrathin, strong, graphene-based membranes that have potential applications for water purification, energy systems, and the chemical industry. But he is also pursuing a low-tech approach to filtration: the use of thin slices of sapwood to remove impurities from drinking water. Using porous membranes that make up the system of tubes and transport cells that circulate water and dissolved minerals within the tree, Karnik’s lab fashioned a filter. Passing contaminated water through the membrane removed more than 99% of bacteria, potentially leading to a simple, safe, inexpensive water purification method for the more than 1 billion people globally who lack access to clean drinking water.
After completing an undergraduate degree from the Indian Institute of Technology at Bombay in 2002, Karnik became interested in “the huge diversity” of topics affected by the nanoscale properties of fluid flow. He earned a PhD at the University of California at Berkeley before joining the MIT faculty in 2007.
“What really drives me is a curiosity to learn about different phenomena—and then make connections between science and technology to turn them into something useful that adds value to society,” he says.
“I always think about what might have lasting impact,” he continues. “What will make a difference a hundred or a thousand years down the line? What will civilization even look like? Having that perspective helps me make important decisions about the direction of my research.”