Effects of NaOCl Aqueous Solutions and Ethyl Alcohol Solutions on Removing Protein Surface Contaminants and Re-establishing Antibacterial Activities of Copper-Alloyed Stainless Steel

Abstract

　Effects of wiping copper-alloyed stainless steel surfaces with disinfectants to remove protein surface contaminants and re-establish their antibacterial activities were quantitatively studied. Disinfectants used were sodium hypochlorite aqueous solutions and ethyl alcohol aqueous solutions. Wiping with NaOCl aqueous solutions effectively removed protein surface contaminants. Ethyl alcohol aqueous solutions were also effective for cleaning, but their efficiency was less than that of NaOCl aqueous solutions. When the amount of residual surface contaminants was reduced to 0.4 ng/mm², the surfaces of the copper-alloyed stainless steel regained antibacterial activities to the same level as those in a clean surface condition.