Tunable backbone-degradable robust tissue adhesives via in situ radical ring-opening polymerization

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials Engineering

Background:

• Developing adhesives with both strong adhesion and controlled degradability is crucial for clinical and environmental applications.
• Current fabrication methods face significant challenges in achieving these dual properties.

Purpose of the Study:

• To propose and demonstrate an in situ radical ring-opening polymerization (rROP) strategy for creating backbone-degradable robust adhesives (BDRAs).
• To engineer BDRAs with tunable properties for diverse substrate adhesion in physiological environments.

Main Methods:

• Utilized a mixture of hydrophobic cyclic ketene acetal and hydrophilic acrylate monomers for adhesive precursors.
• Employed redox-initiated in situ rROP to form a deep covalently interpenetrating network with a degradable backbone.
• Evaluated adhesion strength on various materials and tissues, including wet bone and porcine skin.

Main Results:

• Achieved robust adhesion on diverse substrates, with wet bone adhesion >16 MPa and porcine skin adhesion >150 kPa, surpassing commercial cyanoacrylate adhesives.
• Demonstrated tunable degradability, mechanical modulus (100 kPa–10 GPa), and setting times (seconds–hours).
• Confirmed good biocompatibility in vitro and in vivo.

Conclusions:

• The proposed in situ rROP strategy successfully yields BDRAs with superior adhesion and tunable degradability.
• These BDRAs offer a versatile and biocompatible solution for medical adhesives.
• This approach provides an easy and environmentally friendly method for engineering advanced adhesives.