Effect of incorporation of piezoelectric phases on antibacterial and cellular response of borate bioactive glass

The present study investigates the consequences of incorporation (30 vol %) of piezoelectric Na0.5K0.5NbO3 (NKN) and BaTiO3 (BT) phases and surface polarization (20 kV at 500 degrees C) on in-vitro antibacterial and cellular response of borate bioactive glass (1393B3, BBG). XPS analyses elucidated that the surface chemistry of opti-mally processed composites remains unaffected after surface polarization treatment. The piezoelectric BT and NKN enhance the antibacterial activity of BBG by -(53, 57%) and (51, 54%) for E. coli and S. aureus bacteria stains, respectively. The SEM images of bacteria, adhered on unpolarized and polarized surfaces demonstrate bacteria specific response. The combined action of piezoelectric phase and surface polarization increases the growth rate of osteoblast like MG-63 cells on negatively polarized BBG-BT (30 vol %) and BBG-NKN (30 vol%) composites by -76 and 82% respectively. Overall, the piezoelectric secondary phase incorporated in BBG as well as surface polarization increases the cellular and antibacterial response significantly.