A mechanical metamaterial made from a DNA hydrogel

Area of Science:

• Materials Science
• Biotechnology
• Nanotechnology

Background:

• Metamaterials typically utilize inorganic materials (e.g., silicon, copper) for unique electromagnetic or acoustic properties.
• Applications include cloaking devices, superlenses, and sound absorbers.
• A gap exists in exploring metamaterials with tunable mechanical properties.

Purpose of the Study:

• To demonstrate the fabrication of metamaterials using DNA as a building block.
• To engineer novel meta-hydrogels with unusual mechanical and responsive properties.
• To explore potential applications of DNA-based metamaterials.

Main Methods:

• Utilized a polymerase enzyme to elongate DNA chains.
• Non-covalently assembled DNA into a hydrogel structure.
• Characterized the hierarchical internal structure and mechanical properties of the meta-hydrogel.

Main Results:

• Developed a DNA-based meta-hydrogel with tunable mechanical properties.
• The meta-hydrogel exhibits liquid-like behavior out of water and solid-like behavior in water.
• Demonstrated self-healing and shape-memory capabilities upon water addition and deformation.
• Engineered a proof-of-concept electric circuit using the meta-hydrogel with water as a switch.

Conclusions:

• DNA can serve as a viable building block for creating metamaterials with advanced mechanical functionalities.
• The developed meta-hydrogel offers a unique combination of responsiveness, self-healing, and hierarchical structure.
• This work paves the way for novel applications in soft robotics, sensors, and responsive devices.