Indirect cytocompatibility and antibacterial properties of Zr-Cu-Ag metallic glass coatings

In order to evaluate a possible antibacterial effect of the released ions, specimens (4x4 mm² square metallic glass coatings) were submerged with 7 ml of LB broth and maintained at 37°C inside a shaker (120 rpm) for 1, 5 days, following the same procedure exploited for the ions release evaluation. At each time point the supernatants were collected and used to cultivate bacteria at a defined concentration (1x10⁵ cells/ml); bacteria cultivated with supernatants obtained from ions-free PBT were considered as control. The released ions killing activity was evaluated in terms of metabolic activity that was measured by the alamar blue assay as previously detailed. The same procedure with LB medium for hMSC was repeated.