Injectable Chitin-Poly(ε-caprolactone)/Nanohydroxyapatite Composite Microgels Prepared by Simple Regeneration...

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Injectable hydrogels offer advantages over traditional bone grafts for defect reconstruction.
• Developing advanced materials is crucial for improving bone defect repair outcomes.

Purpose of the Study:

• To develop and characterize nanohydroxyapatite (nHAp) incorporated chitin-poly(ε-caprolactone) (PCL) based injectable composite microgels.
• To evaluate the potential of these microgels for bone defect repair by assessing their physical properties, cytocompatibility, and osteogenic differentiation capacity.

Main Methods:

• Composite microgels were synthesized using a regeneration technique.
• Characterization involved scanning electron microscopy (SEM), Fourier transformed infrared spectroscopy (FTIR), and X-ray diffraction (XRD).
• In vitro studies assessed protein adsorption, cytocompatibility, cell migration, and osteogenic differentiation of rabbit adipose-derived mesenchymal stem cells (rASCs).

Main Results:

• The chitin-PCL-nHAp microgels exhibited enhanced elastic modulus, thermal stability, and shear-thinning behavior, confirming injectability.
• Protein adsorption and cytocompatibility were favorable.
• Microgels promoted early osteogenic differentiation of rASCs, evidenced by elevated expression of osteogenic markers (alkaline phosphatase, osteopontin, osteocalcin).

Conclusions:

• The developed chitin-PCL-nHAp composite microgel is a promising injectable system for regenerating complex bone defects.
• The material's properties and ability to induce osteogenic differentiation support its potential in bone tissue engineering.