Titanium Oxide and Antibacterial Surfaces in Biomedical Devices

Titanium oxide is a heterogeneous catalyst whose efficient photoinduced activity, related to some of its allotropic forms, paved the way for its widespread technological use. Here, we offer a comparative analysis of the use of titanium oxide as coating for materials in biomedical devices. First, we introduce the photoinduced catalytic mechanisms of TiO2 and their action on biological environment and bacteria. Second, we overview the main physical and chemical technologies for structuring suitable TiO2 coatings on biomedical devices. We then present the approaches for in vitro characterization of these surfaces. Finally, we discuss the main aspects of TiO2 photoactivated antimicrobial activity on medical devices and limitations for these types of applications. KEy wORDS: Biomaterial surface modifications, Titanium oxide, Antibacterial properties, Infectionresistant materials Accepted: August 31, 2011 rEViEW due to bacterial colonization and proliferation (1). About half of the 2 million cases of nosocomial infections that occur each year in the United States are associated with indwelling devices (2): these infections generally require a longer period of antibiotic therapy and repeated surgical procedures, resulting in potential risks for the patient and increased costs for the healthcare system. The planktonic bacteria that colonize a device surface tend to form a biofilm and the sessile bacterial cells, enclosed in a self-produced polymeric matrix of this kind, can withstand host immune responses and generally show extraordinary antibiotic resistance (3). Eventually, bacteria rapid multiply and disperse in planktonic form, giving rise DOI: 10.5301/ijao.5000050