The National Science Foundation (NSF) has awarded major grants to members of Syracuse University’s BioInspired Institute , supporting their research into complex biological systems and innovative materials.
Professors M. Lisa Manning, James “Jay” Henderson and Jennifer Ross are working on NSF-sponsored projects that intersect with all four of the institute’s research foci: Drug Discovery, Form and Function, Smart Materials, and the Mechanics of Development and Disease.
Manning, who directs the institute, is excited about the awards, whose merit-review application process is highly competitive. “The grants not only align with our mission, but also indicate that we’re performing world-class research with real-world impact. Furthermore, the funds support graduate and undergraduate students working on the projects as they gain cutting-edge research skills,” she says.
Based in the College of Arts and Sciences , Manning is the William R. Kenan Jr. Professor of Physics. NSF has awarded her a $369,914 grant to study the failure of solid-like materials in industry and nature.
Henderson is BioInspired’s new associate director. A faculty member in the College of Engineering and Computer Science with a courtesy appointment in Arts and Sciences, he has received a $438,000 award to develop a new approach to 4D printing of shape-memory polymers.
Jennifer Ross, chair of the physics department in Arts and Sciences, is the lead investigator of a three-member team, funded at $827,000, to probe the physics of enzyme-powered active materials. Her portion of the three-year award is $293,596.
“Jay’s funded project and my own focus largely on smart materials,” says Manning, referring to compounds (also known as active materials) whose properties change in response to externally applied stimuli, such as stress, light or temperature. “Our work also has applications in the institute’s Form and Function group and the Mechanics of Development and Disease group. Similarly, Jenny’s study of enzyme activity bridges several groups, including Development and Disease, Drug Discovery and Smart Materials.”
Predicting Materials Behavior
Manning’s project builds on her work previously funded by a five-year NSF CAREER grant, awarded to early-career scientists. As a CAREER grant recipient, she studied the behavior of solid-like disordered materials, such as grain in a silo and molecules in glass.
This time, she turns her attention to disordered materials that are actively moving or actively breaking down—“failing,” in materials science parlance. Examples of such behavior span from the rupture of a plastic container to the onslaught of an avalanche or a mudslide. “By understanding how these materials behave while they are failing, we can predict failure events and design materials that resist failure or can fail in precise, pre-programmed ways,” Manning says.
Active materials run the gamut from cells inside biological tissue to herds of animals and crowds of people. Scientists are currently developing a type of active material called “self-propelled colloids.” Standard colloids, such as milk, are made of tiny embedded particles that move from place to place inside a fluid, when heated. In contrast, self-propelled colloidal particles are partly covered with a chemical, allowing them to zoom around without any heat.
This kind of research, Manning explains, may open the door to materials with new functions, such as self-stirring fluids. “New types of active matter are being synthesized in labs across the country, but there are no theories yet for how these materials behave when they are tightly packed together. Our goal is to develop theories that help scientists design active materials with specific functions,” she adds.
Pioneering 4D Printing
Henderson also works with active materials—specifically shape-memory polymers (SMPs) that can be programmed to change shape and stiffness when triggered by a stimulus, such as a change in temperature.
SMPs are natural or artificial materials made of long, repeating chains of molecules that are rigid. But, when heated, they can be “deformed and programmed” into a temporary shape, Henderson says. “Only when the stimulus is applied to the SMP can it return to its ‘remembered,’ original shape. Similar shape-memory behavior is displayed by some metallic alloys.”
He is applying this knowledge to 3D printing, in which a melted thread of plastic, called a filament, is extruded through a tiny nozzle, whose movements are controlled by a computer. The result is a stack of cross-sectional layers of molten plastic that fuse together, forming a 3D object.
Most SMP devices that interface with off-the-shelf 3D printers require composite materials or a mechanical programming step after fabrication. Henderson is using NSF funding to pioneer a novel, single-step fabrication technique. “It offers the potential for future integration with composites for an even higher level of control and functionality,” says Henderson, who is collaborating with Engineering and Computer Science professors Pranav Soman and Teng Zhang.
There are many possible applications for this “Programming-Via-Printing” approach, as Henderson calls it. He references biomedical devices that may change shape during their intended function, such as self-tying sutures, self-deploying cardiovascular stents and self-fitting casts. “Shape-memory polymers are enabling these paradigm-shifting advances,” he says, adding that the aerospace and energy industries also stand to benefit. “They will revolutionize 3D and 4D printing.”
Powering Active Matter at the Molecular Level
Like Henderson and Manning, Ross focuses on the present, but with an eye on the future. Her work resides at the nexus of biology and physics, seeking to understand how cells produce motion, force and work. She particularly wants to know how cells use enzyme-powered, programmable matter to control and move themselves.
Ross says new and emerging technologies, such as self-healing plastic skin, sensor-studded pavement and shape-shifting clothing, are possible only through the lessons learned from the functioning of enzymes—nanoscale machines made of protein that perform all sorts of functions inside cells. “To design any of these futuristic devices, we need materials that are self-powered and assembled hierarchically from energy-using building blocks. Many biological systems, such as cells, plants and humans, are capable of sensing and responding to their environment by moving, changing shape or releasing chemicals,” she says.
Ross relies on enzymes to power new synthetic materials at the molecular level. Central to her work is DNA origami, a technique in which strands of DNA are folded together to make two- and three-dimensional objects. Such objects are tethered to enzymes, much like harnessing a horse, to power the motion of the origami. “The origami will create nanoscale rockets to mimic the nature of the cellular environment that I want to study,” she says. “Some origami shapes will be used to recreate a model system of the environment inside the cell; others will be used to probe that environment. If done carefully and reproducibly, we can use DNA origami to understand the physics occurring inside the cell.”
Just as enzymes can be mobilized to propel micron-sized objects, they conceivably can be scaled up to work at the macroscopic level. “It may lead to roads that heal themselves of potholes or to bridges and dams that signal out for help before they crumble,” Ross says. “These technological inventions draw inspiration from the natural world.”