NSF-Funded Research at UC Santa Barbara Explores How Charged Polymers Could Enable Next-Generation Adhesives and Drug Delivery Systems
UC Santa Barbara materials scientist Omar Saleh has received a three-year, $441,000 grant from the U.S. National Science Foundation (NSF) to study the behavior of charged polymers, work that could lead to new breakthroughs in biomedical adhesives and precision drug delivery.
Polymers, whether natural or synthetic, form the basis of countless modern materials. In their soft, gel-like state, they can interact and self-assemble into microscopic droplets through a process called complex coacervation, where oppositely charged polymers bind together. Saleh’s research seeks to reveal how these interactions occur at the nanoscale, a key step toward engineering polymers that can safely encapsulate and release therapeutic compounds or adhere within biological environments.
“In this project, we aim to understand how mixtures of charged polymers can form droplets with unique properties, such as the ability to encapsulate and deliver drugs or act as adhesives,” said Saleh, professor and chair of UCSB’s Materials Department.
Saleh’s lab is among a small number worldwide capable of performing nanometer-scale measurements of soft polymer systems. Using a specialized instrument called magnetic tweezers, his team applies tiny, precisely controlled forces to individual polymers, tracking their extension and shape changes with sub-nanometer accuracy. These experiments enable researchers to detect how molecular configurations influence coacervation, a process too dynamic for traditional techniques like X-ray crystallography.
The work is paired with computational modeling led by Mark Stevens of Sandia National Laboratories, whose simulations will help interpret the experimental data and explore new polymer geometries. Together, these efforts will clarify how ionic strength, temperature, and polymer architecture affect the structure and phase behavior of complex coacervates.
Saleh notes that while many polymer-based technologies are discovered through trial and error, understanding the underlying physics can unlock entirely new applications and improve existing ones. Beyond advancing fundamental materials science, the grant supports hands-on training for a Ph.D. student, providing experience in high-precision instrumentation and quantitative analysis applicable across scientific disciplines.
“NSF support is so important to the American economy,” Saleh said. “Without funding, research doesn’t happen. These funds directly train the next generation of scientists who will expand our technological capabilities.”