Piezoelectric Nano-Biomaterials for Biomedicine and Tissue Regeneration

Among various classes of biomaterials, the majority of non-centrosymmetric crystalline materials exhibit piezoelectric properties, i.e., the accumulation of charge in response to applied mechanical stress or deformation. Due to the growing interest in nanomaterials, piezoelectric nano-biomaterials have been widely investigated, leading to remarkable advancements throughout the last two decades. Piezoelectric properties, high surface energy, targeting properties, and intricate cell-material interactions render piezoelectric nanomaterials highly attractive for application in therapeutics as well as regenerative medicine. Herein, the major focus is to highlight the wide range of applications of piezoelectric nano-biomaterials in drug delivery, theranostics, and tissue regeneration. After a brief introduction to piezoelectricity, an overview is provided on the major classes of piezoelectric biomaterials as well as a description of the origin of biopiezoelectricity in different tissues and macromolecules. Subsequently, relevant properties and postfabrication strategies of nanostructured piezoelectric biomaterials are discussed aiming to maximize piezoresponse. Finally, recent studies on nano- piezoceramics and piezopolymers are presented, with specific focus on barium titanate, zinc oxide, and polyvinylidene fluoride.