Synergistic Dielectric Modulation and Bioactivity in PVDF/HAP/CCTO Nanocomposites for Smart Bone Regeneration

Replicating the electroactive and dielectric nature of bone remains a major challenge in designing biofunctional scaffolds for regeneration. In this work, flexible nanocomposite films based on polyvinylidene fluoride (PVDF), hydroxyapatite (HAP), and calcium copper titanate (CCTO) were developed to achieve biomimetic electrical behavior and superior osteocompatibility. PVDF/HAP (80/20) matrices were reinforced with 2–15 vol% nano-CCTO synthesized via high-energy ball milling and fabricated through solvent casting. Structural and dielectric analyses revealed a pronounced increase in β-phase crystallinity and interfacial polarization with CCTO loading, yielding a high dielectric constant (εr ≈ 117 at 100 Hz) and enhanced ferroelectric response (Pr ≈ 0.98 μC/cm²). MG-63 osteoblast cultures exhibited excellent adhesion, proliferation, and filopodial extension, particularly on the 10 vol% CCTO film, confirming biocompatibility and cell stimulation by dielectric coupling. The optimized PVDF/HAP/CCTO composite thus represents a multifunctional bioelectroactive material capable of promoting electrically assisted bone tissue regeneration.