Inhibition of Staphylococcus aureus biofilm by a copper-bearing 317L-Cu stainless steel and its corrosion resistance

The present study investigated the antibacterial performance, corrosion resistance and surface properties of antibacterial austenitic 317L-Cu stainless steel (317L-Cu SS). After 4.5 wt% copper was added to 317L stainless steel (317L SS), the new alloy underwent solid solution and aging heat treatment. Fluorescent staining using 4',6-diamidino-2-phenylindole (DAPI) revealed that the 317L-Cu SS showed strong antibacterial efficacy, achieving a 99% inhibition rate of sessile Staphylococcus aureus cells after 5 days. The corrosion data obtained by potentio-dynamic polarization curves indicated that in comparison with 317L SS, the pitting potential and corrosion current density of 317L-Cu slightly decreased due to the addition of Cu. The 317L-Cu SS exhibited no cytotoxicity against zebrafish (Danio rerio) embryos. The experimental results in this study demonstrated that the new alloy has potential applications in medical and daily uses. (C) 2016 Elsevier B.V. All rights reserved.