title: Antibacterial copper-nickel bilayers and multilayer coatings by pulsed laser deposition on titanium.
abstract: Biofouling, especially microfouling, is a major concern with the use of titanium (Ti) in the marine environment as a condenser material in cooling water systems. Earlier, copper-nickel (Cu/Ni) alloys were extensively used in marine environments due to their high corrosion and biofouling resistance. However, the choice of condenser material for the new fast breeder reactor in Kalpakkam is Ti to avoid steam side corrosion problems, which may pose a threat to steam generator parts having sodium as the secondary coolant. This study evaluates the surface modification of Ti using nano films of copper (Cu) and nickel (Ni) to utilize the antibacterial property of copper ions in reducing microfouling. The surface modification of Ti was carried out by the deposition of a Cu/Ni bilayer and (Cu/Ni)(10) multilayer films using a pulsed laser deposition technique. Various surface characterization studies revealed that the deposited Cu/Ni films were thin and nanocrystalline in nature. The antibacterial properties were evaluated using total viable count and epifluorescence microscopic techniques. The results showed an apparent decrease in bacterial attachment on multilayered and bilayered Cu/Ni thin films on Ti surfaces. Comparative studies between the two types of films showed a bigger reduction in numbers of microorganisms on the multilayers.
authors.affiliation: Centre for Nanoscience and Nanotechnology, Sathyabama University, Chennai, India. vinitavishwakarma1@rediffmail.com
authors.forename: Vinita
authors.initials: V
authors.lastname: Vishwakarma
authors.forename: J
authors.initials: J
authors.lastname: Josephine
authors.forename: R P
authors.initials: RP
authors.lastname: George
authors.forename: R
authors.initials: R
authors.lastname: Krishnan
authors.forename: S
authors.initials: S
authors.lastname: Dash
authors.forename: M
authors.initials: M
authors.lastname: Kamruddin
authors.forename: S
authors.initials: S
authors.lastname: Kalavathi
authors.forename: N
authors.initials: N
authors.lastname: Manoharan
authors.forename: A K
authors.initials: AK
authors.lastname: Tyagi
authors.forename: R K
authors.initials: RK
authors.lastname: Dayal
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development; D003300:Copper / Q000737:chemistry / Q000494:pharmacology*; D007834:Lasers; D008386:Marine Biology / Q000379:methods; D008422:Materials Testing; D008856:Microscopy, Fluorescence; D053758:Nanoparticles; D049329:Nanostructures / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry / Q000494:pharmacology*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; C062136:nickel copper alloy; D003300:Copper; D009532:Nickel; D014025:Titanium