A High-Density Hydrogen Bond Locking Strategy for Constructing Anisotropic High-Strength Hydrogel-Based Meniscus...

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Mimicking anisotropic features is essential for creating load-bearing artificial soft tissues, like menisci.
• Existing hydrogels often lack the required mechanical strength and anisotropic properties for such applications.

Purpose of the Study:

• To develop a novel strategy for fabricating high-strength anisotropic hydrogels.
• To evaluate the potential of these hydrogels as meniscal scaffolds for osteoarthritis treatment.

Main Methods:

• A high-density hydrogen bond locking (HDHBL) strategy was employed using poly(N-acryloylsemicarbazide) (PNASC) hydrogels.
• The process involved preloading PNASC hydrogels with a hydrogen bond breaking agent, followed by water exchange to re-establish hydrogen bonds and orient molecular chains.
• A meniscal scaffold was fabricated using 3D printing and the HDHBL strategy, then implanted in rabbit knee joints.

Main Results:

• The fabricated anisotropic hydrogels exhibited superior mechanical properties, including tensile strength >9 MPa, Young's modulus >120 MPa, and fatigue thresholds >1900 J/m².
• The anisotropic meniscal scaffold demonstrated a chondroprotective effect and ameliorated osteoarthritis progression in rabbit knee joints over 12 weeks.
• The HDHBL strategy proved effective in creating oriented microstructures within the hydrogels.

Conclusions:

• The HDHBL strategy successfully produces anisotropic, high-strength hydrogels suitable for load-bearing applications.
• Anisotropic meniscal scaffolds fabricated using this method show therapeutic potential for osteoarthritis.
• This technique broadens the applicability of anisotropic polymer hydrogels in various fields.