Dynamic assembly of complex hierarchical DNA polymer networks by biomolecular active agents

Active assembly of matter is a defining trait of living systems, enabling the creation of far-from-equilibrium materials essential for the functionality of life. This is achieved through energy-dissipative, multi-step processes facilitated by various biomolecular agents for chemical and mechanical assembly of matter. Replicating such assemblies synthetically on small scales remains a challenge. Here, we demonstrate a biomimetic approach to assembling microscale materials using active agents, bypassing typical thermodynamic and diffusive limitations. Specifically, we use two chemically fueled biomolecular agents—DNA polymerase and kinesin—to show a multi-step chemical synthesis and mechanical manipulation process resulting in a DNA biopolymer network with morphologies unattainable by self-assembly alone. DNA polymerase generates DNA globules tethered to microtubules, which then form a fibrous 2D network when driven by kinesin-powered motion. This fibrous morphology results from the interplay between DNA-DNA attraction and propulsion forces from gliding microtubules within kinesin-coated microfluidic cells. Experimental and simulated data confirm that molecular motor activity is essential to this process. Furthermore, we investigate how varying DNA polymerase exposure time and microtubule density affects network formation. This work offers a pathway toward bottom-up fabrication of complex and dynamic microscale materials using active agents, mimicking the sophisticated assembly strategies of living systems.