Programmable DNA Nanosprings with Tunable Chirality

Helical chiral structures are prevalent in nature and play vital roles in both biological and engineering systems. However, precise control over these structures at the nanoscale remains a significant challenge. In this study, we propose a general design strategy for helical chiral DNA structures, facilitating the bottom-up assembly of supercoiled DNA nanosprings with highly customizable structural parameters. Our approach utilizes the independent tuning of inner-module bending and inter-module phase-matching, enabling precise and continuous control over their chirality, screw diameter, and pitch, all within a wire diameter of approximately 10 nm and with minimal DNA sequence redesign. Molecular dynamics simulations show that these nanosprings exhibit conformation-dependent mechanical properties and energy storage capabilities under compression. Furthermore, we observed enhanced circular dichroism signals from their right-handed structural chirality. Compatible with various design techniques, including DNA bricks and DNA origami, the strategy is exttendable to more complex self-assembled DNA structures. Overall, this modular assembly approach offers a novel framework for the precise, programmable design of supramolecular materials with tunable chirality.