PCL Scaffolds with Hardystonite and Magnetite Nanoparticles Under a Pulsed Magnetic Field for Bone Tissue Engineering

Achieving scaffolds with suitable mechanical properties and bioactivity is a crucial need for bone tissue engineering. In this study, we present novel 3D-printed scaffolds composed of poly(ε-caprolactone) (PCL), hardystonite (HT), and Fe 3 O 4 magnetic nanoparticles, designed to combine enhanced mechanical stiffness suitability with responsiveness to pulsed magnetic fields. Scaffold hydrophilicity, degradation, pH stability, and mechanical performance were systematically evaluated in both solid and porous samples, alongside cellular viability and morphology of MG63 and L929 cells under magnetic stimulation. Incorporation of 10 wt% HT and 4 wt% Fe 3 O 4 significantly improved scaffold hydrophilicity (contact angle < 90°) and mechanical strength, with Young's modulus and toughness increasing up to 227.4% and 431%, respectively. Degradation rates were accelerated, reaching ∼12% weight loss over 60 days, while pH remained in the physiological range (7.2–7.6). Cellular assays revealed enhanced viability on nanoparticle-containing scaffolds, further amplified by over 16% under pulsed magnetic field exposure. SEM and fluorescence imaging confirmed improved cell adhesion and spreading, particularly in the presence of both nanoparticles and magnetic stimulation. These results demonstrate that the synergistic integration of HT and Fe 3 O 4 with external magnetic fields not only optimizes scaffold mechanical properties but also promotes bioactivity, presenting a promising strategy for engineering bone scaffolds with tunable mechanical and biological functionality.