Associate Professor Jessica Schiffman, the Professor James M. Douglas Career Development Faculty Fellow in the Chemical Engineering Department, is the principal investigator on a three-year, $340,541 award from the National Science Foundation (NSF). The NSF grant will support her research team’s investigation into new membrane technology that was inspired by the Nepenthes Pitcher Plant.
Schiffman’s NSF project is titled “Collaborative research: Bioinspired liquid-gated membranes reduce biofouling.”
Schiffman’s collaborator on this NSF-funded project is Assistant Professor Caitlin Howell at the University of Maine in the Chemical and Biomedical Engineering Department, a researcher who received an additional NSF award for $304,350 to work on this project. Their approach will enable high-flux, liquid-gated membranes that resist biofouling without the use of biocides or physical cleaning and is based on a biological characteristic of the pitcher plant.
According to Schiffman, ultrafiltration membranes are considered the state-of-the-art material for water treatment because they effectively remove particulates and waterborne pathogens from drinking water. Unfortunately, over time, membranes become fouled and require cleaning, which increases water treatment process downtime. Improving membrane lifetime is vital to decreasing the cost and energy required to produce clean water.
“In nature,” Howell explains, “the Nepenthes Pitcher Plant uses a thin, immobilized, liquid layer to create an ultra-slippery surface which causes insects to slide into its cup.” The researchers say that they were “inspired by the pitcher plant to develop a new approach to membrane design that reduces the adhesion of foulants and thereby enables the membrane's long-term operation.”
By properly selecting a stable “gating liquid” that provides a thin protective layer on the membrane, the researchers can create reversible pore gates that quickly open and shut to enable liquid transport while reducing the ability of foulants to attach. Furthermore, when pressure is released, the gating liquid refills the pores, dislodging contaminants trapped within the pores and enabling flux recovery.
“In addition to improving the functionality of membranes for water purification,” as Schiffman explains, “understanding the materials-biology interface will help inform the design of new membranes for a broad range of separations, including food processing, blood filtration, and protein purification.”
Schiffman heads an interdisciplinary and imaginative research group that designs and applies green materials science toward new solutions to grand challenges in human health. “Our research is interdisciplinary in nature,” Schiffman says, “drawing influences from chemical engineering, materials science, and microbiology.” (October 2019)