ANTIBACTERIAL ACTIVITY OF MULTILAYER SILVER COPPER SURFACE-FILMS ON CATHETER MATERIAL

The antimicrobial activity of Ag, Cu, and layered Ag-Cu surface films, sputter-coated onto several types of catheter material, against clini cal isolates of Staphylococcus epidermidis and Staphylococcus aureus w as evaluated. When 20 muL of a suspension of S. epidermidis or S. aure US (2.68 x 10(6) colony-forming units/mL) was applied onto Ag-Cu- or C u-coated butyl rubber, bacterial numbers were greatly reduced within 1 0 h, and eliminated within 24 h. In contrast, antibacterial activity w as significantly less on uncoated or Ag-coated surfaces. Ag-Cu- or Cu- coated silicon rubber, polyvinylchloride, and teflon were even more ef fective than Ag-Cu- or Cu-coated butyl rubber. Ag-Cu layered surface f ilms also showed antibacterial activity against Pseudomonas aeruginosa biofilm formation. Multiple metal surface film combinations show grea t promise in lowering the incidence of device-associated nosocomial in fections.