Development and characterization of bifunctional conductive and magnetic scaffold based on polyvinyl alcohol/polypyrrole/magnetite composite for neural tissue engineering

The incorporation of electroconductive and magnetic materials into scaffolds for tissue engineering has emerged as an innovative approach to enhance nerve tissue regeneration. In this study, the freeze-drying technique was used to fabricate a bifunctional 3D neural scaffold based on biodegradable polyvinyl alcohol (PVA), incorporating magnetite nanoparticles (Fe₃O₄NPs) and the conductive polymer polypyrrole (PPy). Microstructural and chemical analyses using field emission scanning electron microscopy/energy-dispersive spectrophotometer, x-ray diffraction, and Fourier transform infrared spectroscopy revealed scaffolds with a homogeneous structure, interconnected pores averaging 100 µm, and over 80% porosity, with magnetite evenly distributed in the PVA matrix. The incorporation of Fe₃O₄nanoparticles significantly enhanced the scaffold's compressive strength and elastic modulus, while PPy increased conductivity to levels comparable to those of native neural tissue. The scaffold also exhibited superparamagnetic properties due to Fe₃O₄NPs, as confirmed by vibrating-sample magnetometry analysis. PBS submersion demonstrated water absorption and a 30% weight loss over 24 d.<i>In vitro</i>cytotoxicity tests on SH-SY5Y human neuroblastoma cells cultured on composite scaffolds confirmed cell viability, both with and without pulsed electromagnetic field stimulation. Overall, these results suggest that this scaffold is a promising candidate for neural tissue regeneration.