Alginate-based hydrogels functionalised at the nanoscale using layer-by-layer assembly for potential cartilage repair

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Articular cartilage injuries are challenging to repair due to limited regenerative capacity.
• Current treatments often fail to achieve complete regeneration of significant cartilage defects.

Purpose of the Study:

• To develop functionalized nanoscale hydrogels using Layer-by-Layer (LbL) assembly to promote cartilage healing.
• To create stable and cytocompatible hydrogels incorporating specific biomolecules for enhanced cartilage regeneration.

Main Methods:

• Fabrication of sodium alginate (NaAlg) and gelatin (G) hydrogels via external gelation and crosslinking.
• Functionalization of hydrogels using LbL assembly with poly(styrene sulfonate)/poly(allyl amine) (PSS/PAH) nanolayers, incorporating a peptide (CTATVHL) and TGF-β1.
• Characterization of physico-chemical properties (XPS, ATR-FTIR, rheology) and in vitro cytocompatibility using bovine articular chondrocytes (BAC).

Main Results:

• Successful incorporation of PSS and PAH confirmed by XPS and ATR-FTIR analyses.
• LbL assembly created stable nanolayered hydrogels with enhanced integrity.
• Incorporated biomolecules positively influenced BAC adhesion, proliferation, and glycosaminoglycan secretion.

Conclusions:

• Functionalized alginate-based hydrogels demonstrate excellent potential for chondral regeneration.
• The developed hydrogels exhibit suitable integrity, stability, and cytocompatibility for cartilage repair applications.
• LbL assembly offers a promising strategy for creating advanced biomaterials for regenerative medicine.