Flexible, Electrospun Boron Nitride Nanosheets (BNNS)/Hydroxyapatite -PVDF Nanofibers with Superior Piezoelectric/Ferroelectric, Biocompatible Features for Effective Bone Tissue Regeneration

Piezoelectric/ferroelectric scaffolds are emerging tools in tissue engineering that offer new platforms for the repair and regeneration of damaged soft and hard tissues by means of electrical stimulation. In line with this, boron nitride nanosheets (BNNS)/hydroxyapatite (H)-polyvinylidene fluoride (PVDF) based piezoelectric electrospun nanofibers were developed for effective bone tissue regeneration. BNNS were prepared through a sequential process involving lithium intercalation, followed by hydrothermal exfoliation. Four distinct sets of nanofibers were prepared by altering the concentration of BNNS (2.5 wt.%, 5 wt.%, 10 wt.%) while maintaining a constant concentration of HAP nanoparticles which was prepared by sol-gel method (2.5 wt%) in the PVDF polymer matrix. The piezoelectric/ferroelectric performance of the PVDF-H-BNNS nanofibers were found to be enhanced with the addition of BNNS. The PVDF-H-BNNS nanofibers, with an effective contact area of 1 cm2, exhibited remarkable piezoelectric characteristics, exhibiting a peak voltage of 13 V and a current of 1.63 µA under the influence of 10 N force at a frequency of 10 Hz, showcasing their exceptional electromechanical response. The cytocompatibility studies of PVDF-H-BNNS nanofibers on MG-63 and HOS cell lines reveals excellent viability of nanofibers, akin to that control. Cell proliferation investigations conducted with MG-63 and HOS cell lines on PVDF-H-BNNS showcased the remarkable biocompatibility of the engineered membranes. The PVDF-H-BNNS piezoelectric nanofibers, having exceptional piezo-response and enhanced cytocompatibility, hold promise as ideal candidates for applications in the field of bone tissue engineering.