Living biotic-abiotic materials with temporally programmable actuation
Collaborators: Moumita Das (Rochester Institute of Technology), Jennifer Ross (Syracuse University), Michael Rust (University of Chicago), and Megan Valentine (University of California Santa Barbara)
Funding: NSF DMREF 2119663
We are developing foundational technologies, predictive models, and formulation libraries to pioneer a new class of autonomous reconfigurable materials with self-generated spatiotemporal control. Guided by multi-scale modeling, and leveraging advances in synthetic biology and active matter, we aim to integrate biological circuits into biotic-abiotic composites to engineer materials that self-actuate programmable work cycles. Our design paradigm couples hydrogels to living cytoskeleton layers infused with bacteria that secrete cytoskeleton-modifying proteins on a programmable schedule. Our proof-of-concept design target is a gap-closing micro-actuator that photo-responsively closes and autonomously re-opens at times and locations programmed into the cells. We will capitalize on our team’s unique expertise and strong collaborative track record to engineer living biotic-abiotic materials (BAMs) that unite microbes, proteins, biopolymers, and hydrogels, for in situ bioproduction and self-regulation to autonomously drive actuation and perform work. Our proof-of-concept photo-responsive devices and materials will serve as a powerful testbed that can be leveraged by us and the broader MGI community to manufacture and deploy autonomous BAMs. We are using iterative DBTL cycles to accelerate discovery – linking theory, fabrication, computation, and characterization to establish a broad phase space of structure-mechanics-function relationships. We are partnering with NSF BioPACIFIC Material Innovation Platform to develop high-throughput screening schema and formulation libraries to rapidly optimize and publicly share our material blueprints and technologies. Read more here: www.livingbam.org and https://dmref.org/projects/36.
Design and real-time characterization of topologically active DNA-based materials
Funding: AFOSR Biomaterials FA9550-21-1-0361
The frontier of materials research is to engineer non-equilibrium active materials that can sense, respond, and morph to create active work. Such materials can enable resilient self-healing aircraft and bridges; adaptable self-activating PPE; responsive purification, filtration and flow control in pipelines; and manless search-and-rescue devices that can move and change shape on-demand. Our unique approach to this problem is to use time-varying macromolecular topology to control the rheological and structural properties of composite biomaterials, thereby engineering autonomous biomaterials that can perform programmable activity. DNA is the ideal candidate for this strategy as it naturally exists in different topological states – supercoiled, circular and linear – with enzymes that can convert one topology to another. Further, DNA is highly compatible with a wide range of environments, making it an ideal conduit to confer mechanical tunability into other biological or synthetic materials. We are capitalizing on these unique robustness features of DNA to engineer and interrogate active biomaterials that can self-alter their mechanics and structure by enzymatically-driven topological conversion of DNA. We are creating complex fluids of supercoiled and circular DNA and integrating enzymes that alter their topological state in a tunable time-dependent manner; and incorporating these dense topologically-active DNA solutions into systems of rigid biopolymer rods and colloids. In parallel, we are designing a suite of optical tweezers, microrheology and microscopy techniques to precisely characterize the time-varying rheological and structural properties of the active systems during enzymatic activity. We expect to measure completely unique and emergent non-equilibrium mechanics and structure that we can tune with macromolecular knobs. This highly adaptable and transferrable approach to active matter can be incorporated into numerous materials to produce novel non-equilibrium properties and responses. The techniques we will develop will also be broadly applicable to the wide variety of active materials currently under intense investigation.
Controlling colloidal materials with circadian clocks
Collaborators: Moumita Das (Rochester Institute of Technology), Jennifer Ross (Syracuse University), and Michael Rust (University of Chicago)
Funding: WM Keck Foundation Research Grant, RCSA Scialog Innovation Grant
The frontier of materials research is to engineer “intelligent” materials that can sense, decide, and move to create active work. While biology has already engineered such autonomous systems by using cascading chemical reactions and energy-utilizing molecular components, humans currently have no capability to build similar non-equilibrium, multi-component systems. We take a unique route to addressing this need: the programmed coupling of biopolymer networks derived from the cytoskeleton with the robust timekeeping of circadian oscillator proteins to create biomaterials that can rhythmically alter their mechanical properties. Guided by predictive mathematical modeling, we are engineering a suite of tunable materials that can autonomously stiffen and soften through rhythmic crosslinking. Beyond the practical goal of creating a new platform of smart biomaterials, this work will elucidate the fundamental principles underlying dynamically self-regulating biomolecular networks. By fusing the information processing and signaling capabilities of circadian clocks with the mechanical tunability and versatility of the cytoskeleton, this revolutionary approach to materials engineering has the potential to create an entirely new class of autonomously active materials that can not only intelligently respond to external signals, but also anticipate future demands.
DNA transport in cell-mimicking environments
Collaborators: Ryan McGorty (University of San Diego)
Funding: NIH NIGMS R15
This project seeks to understand intracellular transport and spatial organization of biomolecules – specifically DNA – using in vitro biomimetic environments and a suite of optical and rheological tools. Undergraduate students are leading the development of complex yet tunable cytoskeletons driven by molecular motors and confined by cell-like vesicles, while using various microscopy and rheology modalities and analyses to visualize and quantify the dynamics, structure, and mechanics of DNA and cytoskeleton. This in vitro platform that we are developing will be widely available to aid health researchers to understand diverse intracellular processes; and the scientific results of the project will elucidate how macromolecules or complexes, such as viral genomes or organelles, are transported and spatially organized by the active cytoskeleton in cells.