Rapid Fabrication of MgNH₄PO₄·H₂O/SrHPO₄ Porous Composite Scaffolds with Improved Radiopacity via 3D Printing Process

Area of Science:

• Biomaterials Science
• Orthopedic Engineering
• Radiology

Background:

• Bone repair scaffolds require high radiopacity for clinical visualization, but intrinsic radiopacity is often insufficient.
• Integrating X-ray contrast agents is a viable strategy to enhance scaffold radiopacity.

Purpose of the Study:

• To fabricate and characterize MgNH4PO4·H2O/SrHPO4 3D porous composite scaffolds with improved radiopacity using 3D printing.
• To evaluate the radiopacity, degradation, and cytocompatibility of these novel composite scaffolds for bone repair applications.

Main Methods:

• Fabrication of composite scaffolds using 3D printing.
• Characterization using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS).
• Assessment of radiopacity, porosity, in vitro degradation, and cytotoxicity on MC3T3-E1 cells.

Main Results:

• Radiopacity increased with higher SrHPO4 content, reaching equivalence to a 6.8 mm Al ladder at 9.34% SrHPO4.
• Scaffolds exhibited sustainable degradation over 28 days, releasing Mg, Sr, and P elements.
• The 9.34% SrHPO4 composite scaffolds showed superior cytocompatibility and supported cell adhesion.

Conclusions:

• MgNH4PO4·H2O/SrHPO4 composite scaffolds demonstrate enhanced radiopacity and good biocompatibility.
• These scaffolds show significant potential for clinical applications in bone repair and imaging.