Bioactive ZnO Decorated PVDF‐Based Piezoelectric, Osteoconductive Nanofibrous Coatings for Orthopedic Implants

ABSTRACT Surface modification of titanium‐based orthopedic implants has been investigated over the last decades to promote better bone‐to‐implant association, osseointegration, and fracture healing. Yet, post‐surgical failure of coated orthopedic implants occurs due to poor adhesive strength, fatigue failure, high wear rate of coated materials, low biocompatibility, limited osseointegration, and stress‐shielding effect. Therefore, there is an unmet clinical need to develop a smart coating strategy. Herein, we have created an electrospun nanofibrous coating for Ti‐implants using piezoelectric Polyvinylidene fluoride (PVDF) polymer reinforced with osteoconductive nanofiller Zinc oxide (ZnO). We have found that by varying the ZnO content from 0.5 to 2.0 wt.% in the PVDF matrix, we can modulate the electrospun coating's mechanical, thermal, physicochemical stability, and piezoelectric characteristics. Our results proved that PVDF‐ZnO nanofibrous coatings exhibit almost ~3–4 fold increase in the piezoelectric d 33 coefficient as well as output voltage, compared to pure PVDF using Piezo‐responsive Force Microscopy (PFM). Furthermore, electrically poled piezoelectric PVDF‐ZnO nanofibers also demonstrated a significant increment (~5‐fold) in collagen deposition, hydroxyapatite formation, and improved bio‐ and hemo‐compatibility compared to unpoled nanofibers. Furthermore, through the in vitro experiments, we have confirmed that the piezoelectric PVDF‐ZnO nanofibrous activates calcium‐calmodulin mediated cellular pathway to induce cell adhesion, proliferation, and cell spreading in the osteoblast cells. Nonetheless, using the biomimetic mechanical bioreactor, we have investigated the piezoelectricity‐mediated increased focal adhesion and enhanced F‐actin production under the physiologically relevant (i.e., 1%) mechanical strain in bone cells. Moreover, the current study elucidates the piezoelectric‐based smart, multifunctional coating strategies for developing an osteoconductive implant.