3D-printed Ti₃C₂/polycaprolactone composite scaffold with a DOPA-SDF1 surface modified for bone repair

Area of Science:

• Biomaterials Science
• Regenerative Medicine
• Tissue Engineering

Background:

• Large bone defects pose significant challenges in reconstructive surgery.
• 3D printing offers custom scaffolds for bone regeneration.
• Electrical stimulation (ES) aids bone healing by promoting cell activity.

Purpose of the Study:

• To develop a multifunctional 3D printed scaffold combined with ES for enhanced bone defect therapy.
• To create a scaffold with improved stem cell recruitment and osteogenic properties.
• To evaluate the efficacy of the scaffold and ES in promoting bone regeneration.

Main Methods:

• Fabrication of polycaprolactone (PCL) and Ti3C2 scaffolds using 3D printing.
• Loading of DOPA-modified stromal cell derived factor 1 (DOPA-SDF1) onto scaffolds for stem cell recruitment.
• Assessment of scaffold properties including hydrophilicity, conductivity, antibacterial activity, and biocompatibility.
• In vitro evaluation of osteogenic gene expression with pulse ES (PES) treatment.
• In vivo study of tibial plateau defect repair using the DOPA-SDF1@PCL#Ti3C2 scaffold with and without PES.

Main Results:

• The DOPA-SDF1@PCL#Ti3C2 scaffold exhibited excellent hydrophilicity, electrical conductivity, antibacterial properties, biocompatibility, and stem cell recruitment.
• Pulse ES treatment significantly increased osteogenic gene expression in cells on the scaffold.
• In vivo experiments demonstrated that the scaffold promoted new bone and collagen fiber formation.
• Combined scaffold and PES therapy further improved the bone defect regeneration rate.

Conclusions:

• The developed 3D printed scaffold (DOPA-SDF1@PCL#Ti3C2) offers a promising strategy for bone defect repair.
• The combination of stem cell recruitment and electrical stimulation enhances bone regeneration.
• This approach could expand the application of adjuvant therapies like ES in treating large bone injuries.