The intersection of living and synthetic materials has always captured the imagination of people, from science-fiction films developing ideas of cyborg humanoids, to the healthcare industry creating prosthetic limbs nearly indistinguishable from actual limbs. This intersection is an emerging point of research in materials science, and UC Santa Barbara (UCSB) now has a leading role in its development.
In late August, Megan Valentine, a professor of mechanical engineering and the co-director of the California NanoSystems Institute at UCSB, was awarded a $1.8 million grant by the National Science Foundation to develop autonomous and self-programmable materials that blur the line between the living and the synthetic. She will be collaborating with researchers across five universities and three time zones, their fields of expertise ranging from genetics and protein biophysics to materials science and advanced modeling.
In an interview with The Bottom Line (TBL), Valentine sheds light on the key objectives and goals of the research.
“The goal of the project is to design and manufacture self-directed, programmable and reconfigurable materials capable of producing force and motion. We will achieve this by integrating living (biotic) and synthetic (abiotic) components into polymer composites,” Valentine says.
Polymer composites are essentially a mixture of two different materials that create a new, enhanced material. “By combining these very different types of materials, we can capture the adaptive and multifunctional properties of living organisms, while generating robust engineering materials that are stronger and longer-lasting so they can be more easily manufactured, shipped, and stored.”
The project will create biotic-abiotic devices that harness bacteria cells and protein-based motors to power hydrogel actuators, and different schools will lead different parts of the research project. Hydrogels are webs of polymer networks that are composed almost entirely of water — almost like a wet sponge. They are able to swell, shrink, twist, and bend in a variety of ways depending on the stimuli applied to them.
As such, they will serve a key function in the mechanical motion and force of the biotic-abiotic materials being developed. At UCSB, Valentine will be leading the hydrogel design work and the development of the methods for mechanical characterization of the device prototypes. This involves understanding how the hydrogel will respond to stretching, how it will interact with cells and proteins, and how researchers can optimize the coupling between the biological and manmade elements to improve the ability of the materials and devices to change shape, lift, and move.
As groundbreaking as this research will be, it is not without its fair share of obstacles.
“There will be a lot of challenges — and opportunities — in this project as there are in any research that is truly pushing the limits of our current understanding. As one example, we will need to learn how to program bacteria to manufacture and deliver specific molecules on specific schedules, and then embed them into polymer composites that not only provide the appropriate environment to support cell growth, but also provide the correct mechanical environment so that the molecular activity can be transformed into large-scale bio-powered motion. This will require innovation, teamwork and coordination among collaborators working at 5 different universities in 3 different time zones” Valentine explained.
However, she looks forward to these challenges because they make her work exciting. The challenges lead to breakthroughs and the breakthroughs lead to incredible results. The results of this project could have major implications on healthcare, robotics, packaging, and infrastructure. For instance, one possible application is the creation of prosthetic limbs that can sense the environment around them and even heal themselves when damaged.
Valentine is also excited about how the research will benefit students. “The grant will provide opportunities for training students in how to incorporate biological circuits and elements into designer materials and then the deployment of those materials in useful devices that can move, grab and lift. This type of interdisciplinary training will help the students and post-doctoral researchers who work on the project become the next generation of leaders in engineering and materials science,” she says.
This type of technology that Valentine and her collaborators are trying to develop may seem straight out of a science-fiction movie, but it is well within our grasp.