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Advances in Materials Research Volume 1, Number 4, December 2012 , pages 311-347 DOI: https://doi.org/10.12989/amr.2012.1.4.311 |
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Bactericidal and wound disinfection efficacy of nanostructured titania |
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Abdul-Majeed Azad, Asem Aboelzahab and Vijay Goel
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| Abstract | ||
| Infections are caused due to the infiltration of tissue or organ space by infectious bacterial agents, among which Staphylococcus aureus bacteria are clinically most relevant. While current treatment modalities are in general quite effective, several bacterial strains exhibit high resistance to them, leading to complications and additional surgeries, thereby increasing the patient morbidity rates. Titanium dioxide is a celebrated photoactive material and has been utilized extensively in antibacterial functions, making it a leading infection mitigating agent. In view of the property amelioration in materials via nanofication, free-standing titania nanofibers (pure and nominally doped) and nanocoatings (on Ti and Ti6Al4V implants) were fabricated and evaluated to assess their efficacy to mitigate the viability and growth of S. aureus upon brief (30 s) activation by a portable hand-held infrared laser. In order to gauge the effect of exposure and its correlation with the antibacterial activities, both isolated (only titania substrate) and simultaneous (substrate submerged in the bacterial suspension) activations were performed. The bactericidal efficacy of the IR-activated TiO2 nanocoatings was also tested against E. coli biofilms. Toxicity study was conducted to assess any potential harm to the tissue cells in the presence of photoactivated materials. These investigations showed that the photoactivated titania nanofibers caused greater than 97% bacterial necrosis of S. aureus. In the case of titania-coated Ti-implant surrogates, the bactericidal efficacy exceeded 90% in the case of pre-activation and was 100% in the case of simultaneous-activation. In addition to their high bactericidal efficacy against S. aureus, the benignity of titania nanofibers and nanocoatings towards tissue cells during in-vivo exposure was also demonstrated, making them safe for use in implant devices. | ||
| Key Words | ||
| titanium dioxide; doped-titanium dioxide; titanium implant; nanofibers; nanotubes; staphylococcus aureus; photoactivation; infra red laser; infection mitigation; electron microscopy; confocal microscopy | ||
| Address | ||
| Abdul-Majeed Azad: Chemical Engineering Department, The University of Toledo, USA; Asem Aboelzahab: Bioengineering Department, The University of Toledo, 5051 Nitschke Hall, 2801 W. Bancroft St., Toledo, OH 43606-3390, USA; Vijay Goel: Bioengineering Department, The University of Toledo, 5051 Nitschke Hall, 2801 W. Bancroft St., Toledo, OH 43606-3390, USA; Department of Orthopedic Surgery, The University of Toledo, Toledo, Ohio 435606-3390, USA | ||
