title: Fe3O4/TiO2 core/shell magnetic nanoparticle-based photokilling of pathogenic bacteria.
abstract: OBJECTIVE
  We demonstrate a photokilling approach for pathogenic bacteria using magnetic nanoparticles as photokilling nanoprobes.
  
  
  METHODS
  The nanoprobes are composed of iron oxide/titania (Fe(3)O(4)/TiO(2)) core/shell magnetic nanoparticles. The titanium layer on the magnetic nanoprobes plays two roles: as a photokilling agent and as an affinity substrate for pathogenic bacteria. The magnetic property of the nanoprobes allows the resultant nanoprobe-target species conjugates to be readily aggregated at a small spot under external magnetic field for conducting photokilling treatment. Therefore, damage to nontarget cells can be reduced.
  
  
  RESULTS
  The results show that Fe(3)O(4)/TiO(2) core/shell magnetic nanoparticles do not only have the capacity to target pathogenic bacteria, including Gram-negative, Gram-positive and antibiotic-resistant bacteria, but they can also be used to effectively inhibit the cell growth of the bacteria (>99.9%) targeted by the magnetic nanoparticles under irradiation of a low-power UV lamp (λ(max) ∼306 nm, 0.412 mW/cm(2)) within 15 min.
  
  
  CONCLUSIONS
  The potential application of this approach is in the treatment of cutaneous bacterial infections.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University, Hsinchu 300, Taiwan.
authors.forename: Wei-Jen
authors.initials: WJ
authors.lastname: Chen
authors.forename: Yu-Chie
authors.initials: YC
authors.lastname: Chen
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects* / Q000528:radiation effects*; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D053758:Nanoparticles / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D000900:Anti-Bacterial Agents; D005290:Ferric Compounds; C009495:titanium dioxide; C000499:ferric oxide; D014025:Titanium