Nanowhisker glues for fatigue-resistant bioadhesion and interfacial functionalization.

Area of Science:

• Biomaterials Science
• Nanotechnology
• Tissue Engineering

Background:

• Bioadhesives are crucial for wound management and wearable devices, but existing nanoparticle and polymer-based options exhibit weak adhesion, fatigue vulnerability, and poor tissue interaction.
• Tissue barriers and suboptimal interactions limit the performance of current bioadhesives, necessitating advancements in fatigue resistance and functionality.

Purpose of the Study:

• To develop fatigue-resistant functional bioadhesives using rationally designed chitosan nanowhiskers.
• To enhance bioadhesive performance by improving tissue anchorage, fatigue resistance, and enabling interfacial functionalization.

Main Methods:

• Chitosan nanowhiskers were designed to leverage high aspect ratio, rigidity, and network-forming properties for bioadhesion.
• Deployment strategies including chemical enhancers, microneedle rollers, and ultrasound were employed to improve tissue integration.
• Transmission electron microscopy was used to analyze the nanostructure of the bioadhesive-tissue interface.

Main Results:

• The developed chitosan nanowhisker glues achieved fatigue-resistant bioadhesion and interfacial functionalization.
• When combined with a tough hydrogel, the nanowhisker glue demonstrated an interfacial fatigue threshold of 382 J/m² and adhesion energy over 1000 J/m².
• Microscopy revealed a unique sandwiched nanowhisker layer interpenetrated with hydrogels and tissues, creating a robust interface that arrests cracks.

Conclusions:

• Rationally designed chitosan nanowhisker glues offer unprecedented fatigue resistance and versatile interfacial functionalization for bioadhesives.
• The enhanced interfacial properties and crack-arresting mechanism significantly improve bioadhesive performance.
• This advancement opens new avenues for medical and engineering applications requiring durable and functional bioadhesion.