Non-equilibrium cyclic conformations of DNA under electrokinetic confinement

Classic nanofluidic devices rely on geometric confinement to regulate single polymer shape and dictate chain behavior. Although these devices have led to various applications, their static nature hinders real-time control over molecular conformation. The reversible electrokinetic confinement (RECON) technique allows time-dependent regulation of DNA shapes in nanowells by dynamically adjusting field-induced confinement.

In this study, researchers demonstrate that applying fluctuating confinement using random and periodic signals can induce the confined polymer to attain diverse non-equilibrium states. The specific configurations are measured by their radius of gyration tensor. When periodic driving is applied, the device facilitates controlled cycling among different conformational states, revealing hysteresis in the shape anisotropy modulation.

The interplay between driving frequency, driving amplitude, and resulting hysteresis is quantified. By establishing RECON as a platform for actively manipulating individual molecules, this research opens up new avenues for studying non-equilibrium polymer physics and the creation of high-throughput, dynamically adjustable nanofluidic devices.