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Abstract Polymer topology, which plays a principal role in the rheology of polymeric fluids, and non‐equilibrium materials, which exhibit time‐varying rheological properties, are topics of intense investigation. Here, composites of circular DNA and dextran are pushed out‐of‐equilibrium via enzymatic digestion of DNA rings to linear fragments. These time‐resolved rheology measurements reveal discrete state‐switching, with composites undergoing abrupt transitions between dissipative and elastic‐like states. The gating time and lifetime of the elastic‐like states, and the magnitude and sharpness of the transitions, are surprisingly decorrelated from digestion rates and non‐monotonically depend on the DNA fraction. These results are modeled using sigmoidal two‐state functions to show that bulk state‐switching can arise from continuous molecular‐level activity due to the necessity for cooperative percolation of entanglements to support macroscopic stresses. This platform, coupling the tunability of topological composites with the power of enzymatic reactions, may be leveraged for diverse material applications from wound‐healing to self‐repairing infrastructure. 

Abstract DNA serves as a model system in polymer physics due to its ability to be obtained as a uniform polymer with controllable topology and nonequilibrium behavior. Currently, a major obstacle in the widespread adoption of DNA is obtaining it on a scale and cost basis that accommodates bulk rheology and high‐throughput screening. To address this, recent advancements in bioreactor‐based plasmid DNA production is coupled with anion exchange chromatography producing a unified approach to generating gram‐scale quantities of monodisperse DNA. With this method, 1.1 grams of DNA is obtained per batch to generate solutions with concentrations up to 116 mg mL⁻¹. This solution of uniform supercoiled and relaxed circular plasmid DNA, is roughly 69 times greater than the overlap concentration. The utility of this method is demonstrated by performing bulk rheology measurements at sample volumes up to 1 mL on DNA of different lengths, topologies, and concentrations. The measured elastic moduli are orders of magnitude larger than those previously reported for DNA and allowed for the construction of a time‐concentration superposition curve that spans 12 decades of frequency. Ultimately, these results can provide important insights into the dynamics of ring polymers and the nature of highly condensed DNA dynamics.