Bioinspired Self-Growing Layered Hydrogel Enabled by Catechol Chemistry-Mediated Interfacial Catalytic System

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials Engineering

Background:

• Layered structural hydrogels are crucial for applications like artificial muscles, wound healing, and soft robotics.
• Current methods for preparing layered hydrogels are often slow and inefficient, hindering broader adoption.
• There is a need for rapid and controllable fabrication techniques for complex hydrogel architectures.

Purpose of the Study:

• To develop a rapid and efficient strategy for fabricating tissue-inspired layered hydrogels.
• To demonstrate a self-growth approach utilizing interfacial catalytic polymerization.
• To enable customizable physicochemical properties and complex patterns in layered hydrogels.

Main Methods:

• An interfacial catalytic self-growth strategy was employed, inspired by biological self-growth.
• Catechol chemistry, specifically tannic acid-metal ion (TA-Fe3+) complexes, mediated a self-catalytic system.
• Hydrogel layers were grown via rapid solid-liquid interfacial polymerization, avoiding bulk solution polymerization.

Main Results:

• The strategy enabled rapid, controlled growth of layered hydrogels by adjusting parameters like growth time and Fe3+/TA ratio.
• Various layered hydrogels and complex patterns with tunable properties were successfully fabricated.
• A self-adhesive layered hydrogel was created and demonstrated as a wearable strain sensor for monitoring physiological activities.

Conclusions:

• The demonstrated interfacial catalytic self-growth strategy offers a novel and efficient route for designing and fabricating advanced layered hydrogel materials.
• This method overcomes limitations of existing techniques, paving the way for new applications in soft robotics, wearable electronics, and biomedical fields.
• The ability to create customizable, self-adhesive hydrogels expands their potential in sensing and wearable technology.