UMD’s Das Named Emerging Investigator

Siddhartha Das, associate professor of mechanical engineering at the University of Maryland, has been named an Emerging Investigator by the journal Soft Matter.

In conjunction with this recognition, Soft Matter has published a new paper by Das and doctoral student Turash Haque Pial on the properties of polyelectrolyte (PE) brushes. In addition, the journal’s has published an interview with Das on its blog.

Such brushes, which are represented by charged PE chains densely grafted to a surface, are useful in drug delivery, water harvesting, oil treatment, and many other applications. Their effectiveness, however, depends on the responsiveness of the PE molecules to specific environmental stimuli. While their properties and responsiveness have been studied extensively, researchers have been unable until now to gain a full atomistic understanding of their behavior.

Das’s research fills this gap by using all-atom molecular dynamic (MD) simulations, which are yielding an unprecedented understanding of the structure, properties, and behavior of the ions and water molecules within PE brushes. In this particular paper published in Soft Matter, Das and his student take the modeling effort even further forward. The team uses machine learning to improve the predictions of the conditions that define the properties of water molecules (such as water-water hydrogen bonds) inside strong confinement imposed by the densely grafted brush layer that disrupts the connectivity among the water molecules.

Das and his research team at UMD have conducted several prior studies that examine other PE brush properties, using atomistic simulations.

“With our approach, we’ve been able to observe the intriguing behavior of PE brushes with a level of atomistic resolution that just wasn’t available before,” Das said. “The results can help us understand how we can maximize their effectiveness across a wide range of applications.”

A UMD faculty member since 2014, Das conducts research on the science and engineering of soft and polymeric materials, interfacial transport, and small-scale fluid mechanics for fundamental discoveries, including in ion dynamics at soft interfaces, liquid transport in soft-material-functionalized nanochannels, drop behavior on squishy surfaces, and charge-driven nanoparticle-lipid-bilayer interactions. His research supports some of today’s most advanced applications in additive manufacturing.

Das has published more than 170 journal papers, including in Nature Materials, Science Advances, PNAS, Nucleic Acid Research, Nature Communications, Advanced Materials, ACS Nano (October 2021 and April 2021), Matter, and Macromolecules. He is a Fellow of the Institute of Physics and also of the Royal Society of Chemistry. In July 2022, he was elected a Fellow of the Institute of Engineering Technology (IET), based in the United Kingdom.

Published March 17, 2023