Broad Spectrum Microbicidal Activity of Photocatalysis by TiO2

Abstract

Photocatalytically active titanium dioxide (TiO 2 ) is widely used as a self-cleaning and self-disinfecting material in many applications to keep environments biologically clean. Several studies on the inactivation of bacteria and viruses by photocatalytic reactions have also been reported; however, only few studies evaluated the spectrum of the microbicidal activity with photocatalysis for various species. There is a need to confirm the expected OPEN ACCESSCatalysts 2013, 3 311 effectiveness of disinfection by photocatalysis against multidrug-resistant bacteria and viruses. In this study, microbicidal activity of photocatalysis was evaluated by comparing the inactivation of various species of bacteria and viruses when their suspensions were dropped on the surface of TiO 2 -coated glass. Gram-positive bacteria, e.g., methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, and penicillin-resistant Streptococcus pneumoniae, were easily inactivated by photocatalysis, whereas some gram-negative bacteria, e.g., Escherichia coli and multidrug-resistant Pseudomonas aeruginosa, were gradually inactivated by photocatalysis. Influenza virus, an enveloped virus, was significantly inactivated by photocatalysis compared with feline calicivirus, a non-enveloped virus. The effectiveness of microbicidal activity by photocatalysis may depend on the surface structure. However, they are effectively inactivated by photocatalysis on the surface of TiO 2 -coated glass. Our data emphasize that effective cleaning and disinfection by photocatalysis in nosocomial settings prevents pathogen transmission.

Accelerated Antibacterial Inactivation on 2D Cu-Titania Surfaces: Latest Developments and Critical Issues

“…Cu has been widely reported in the last decade to increase the bactericidal activity of TiO 2 [17,[37][38]51,59,86,[101][102][103][104][109][110][111][112][113][114][115][116][117][118][119][120]132]. This section presents some sputtered materials in health facilities, garments and many artifracts used in hospitals facilities [18][19][20][21].…”

Recent Developments in Accelerated Antibacterial Inactivation on 2D Cu-Titania Surfaces under Indoor Visible Light

“…In the last decade, Cu has been widely reported to increase the bactericidal activity of TiO 2 [13,22,42,43,56,64,94,[112][113][114][115][132][133][134][135][136][137][138][139][140][141][142]153]. This section presents some relevant developments (and references) of work regarding bacterial inactivation mediated by TiO 2 /Cu powders and TiO 2 /Cu surfaces by catalysis and photocatalysis.…”

“…These (ROS) radicals are HO • , O 2 •− , and HO 2 • , and have been documented and characterized for most of their properties such as concentration, lifetimes, spectra, and redox potentials by numerous researchers. Linsebigler et al [41], Nakano et al [42], Fujishima et al [43], Douad et al [44], Griesser et al [45], and Hu et al [46] reported the photocatalytic activity of TiO 2 thin films. However, more work using fast kinetics by femto-and picosecond spectroscopy in the visible region is still necessary to identify the nature and lifetime of these ROS species intervening in the individual pathogen inactivation.…”

Antibiofilm Activity of Epoxy/Ag-TiO2 Polymer Nanocomposite Coatings against Staphylococcus Aureus and Escherichia Coli

“…The interest in inorganic disinfectants such as metal oxide nanoparticles (NPs) is increasing. In the last decade, many studies describing the photocatalytic inactivation of bacteria using doped and undoped TiO2 coated on different substrates have been reported, including silver doped TiO2 [3][4][5][6]. A majority of these articles is focused on powder materials and thin films of TiO2 or doped TiO2.…”