# Design and Characterization of DX‐Tile DNA Nanostar‐Based Hydrogels

## TL;DR

This paper introduces a new type of DNA hydrogel with improved design and mechanical properties, suitable for biomedical applications like tissue engineering.

## Contribution

The study introduces multi-arm DX-tile motifs to enhance DNA hydrogel design flexibility and functionalization.

## Key findings

- Modifying structural parameters allows fine control over hydrogel mechanical properties.
- Functionalization can be achieved without compromising physical properties.
- The DNA hydrogels are printable and scalable for biomedical use.

## Abstract

Pure deoxyribonucleic acid (DNA) hydrogels synthesized via the hybridization of multi‐arm DNA tiles (DNA nanostars) are uniquely programmable and functionalizable biomaterials, suitable for applications ranging from biosensing to cell‐free protein production and soft tissue engineering. However, the full potential offered by DNA molecules in terms of design flexibility and functionalization has not yet been leveraged for pure DNA hydrogels, thus reducing their versatility and broader use. In this study, we introduce multi‐arm double‐crossover (DX)‐tile motifs, often used in wireframe DNA nanoparticles assembly, to enable greater control over the hydrogel's mechanical properties and facilitate functionalization. Specifically, we demonstrate that modifying structural design parameters, such as the arm geometry, length, valency, and linker design, allows for fine control of the elastic modulus and viscoelastic properties of the hydrogels. We also show that their functionalization can be performed without compromising the hydrogels' physical properties and exhibit enhanced mechanical strength and tunable properties, compared to simple duplex‐based DNA hydrogels. Furthermore, these DNA hydrogels demonstrated printability and scalability, which pave the way toward the development of novel formulations and bioinks for the rational design of soft tissue engineering scaffolds and broaden the use of DNA hydrogels for other biomedical applications.

In this study, the authors demonstrated that DNA DX‐tile‐based multi‐arm motifs can be used to assemble pure DNA hydrogels, offering greater design flexibility and enhanced control over their mechanical properties and functionalization capabilities compared to single duplex‐based DNA hydrogels. They also showed that these hydrogels are printable, supporting their scalability.