Gelatin-assisted incorporation of vancomycin-loaded PLGA microspheres into 3D-printed biphasic calcium phosphate scaffolds for bone repair

Infected bone defects require structural support and prolonged local antibiotic delivery. Vancomycin (VAN)-loaded poly (lactic- co -glycolic acid) (PLGA) microspheres were incorporated into gelatin-modified 3D-printed biphasic calcium phosphate (BCP) scaffolds. The 3:2 formulation achieved 25.18% drug loading and approximately 190 μm mean size. Gelatin formed a continuous pore-wall layer while preserving main channels. Porosity decreased from 68.8% to 50.2%, while compressive strength increased from 5.57 to 10.46 MPa. Directly loaded VAN released mainly within 5 days, whereas BCP/Gel/PLGA released 31.7% on day 5 and 81.2% on day 28. It produced an approximately 15 mm inhibition zone against S. aureus at 24 h and favorable indirect cytocompatibility and osteogenic responses. The scaffold integrates ceramic support, gelatin-modified pore walls, and prolonged PLGA delivery.