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For the inactivation of mold spores by UVC irradiation, with ozone acting as a promoter, TiO2 nanoparticles may act better as a “sun block” than as a photocatalytic disinfectant

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Abstract

Fungal spores are known as critical indoor allergens, and indoor air purification techniques including photocatalytic disinfection using titanium dioxide (TiO2), ultraviolet germicidal irradiation (UVGI) and ozonation, have been considerably investigated. However, most of the research is in regard to photocatalytic disinfection, focused on the anti-bacterial efficacy of TiO2 nanoparticles (NPs). Furthermore, some research even showed that the photocatalytic antifungal efficacy of TiO2 NPs may not be that significant. Thus, investigating the reasons behind the non-significant antifungal efficacy of TiO2 photocatalytic disinfection and enhancing the antifungal efficacy is indispensable. In this study, ozone was employed to improve the photocatalytic antifungal efficacy of the TiO2 NPs and nano-metal supported on TiO2 NPs. The commercial TiO2 NPs (Degussa (Evonik) P25) served as a good support, and incipient wetness impregnation was successfully exploited to prepare oxidized nano-metals (Ag, Cu and Ni) in this study. There were two surfaces (quartz and putty) used in the inactivation experiments of Aspergillus niger spores which were manipulated under two conditions: exposed to ultraviolet (UVC) light, and exposed to UVC and ozone simultaneously. The SEM images demonstrated that the spores were sheltered from UVC light in the microcracks between TiO2 agglomerates. When irradiating with UVC, the A. niger spores on the two testing surfaces, without TiO2 NPs, were inactivated faster than those with TiO2 NPs, implying a “sun block” effect of this material and a lower photocatalytic antifungal efficacy than UVGI. On both surfaces, the inactivation rate constants (k) of A. niger spores exposed to UVC and ozone simultaneously (on quartz: k = 2.09–6.94 h−1, on putty: k = 3.17–6.66 h−1) were better than those exposed to only UVC (on quartz: k = 1.80–5.89 h−1; on putty: k = 2.97–3.98 h−1), indicating ozone can enhance the UVGI antifungal efficacy.

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Notes and references

  1. A. Pringle, Asthma and the Diversity of Fungal Spores in Air, PLoS Pathog., 2013, 9, e1003371.

    Article  CAS  Google Scholar 

  2. H. A. Burge, An update on pollen and fungal spore aerobiology, J. Allergy Clin. Immunol., 2002, 110, 544–552.

    Article  Google Scholar 

  3. F. Fung and W. G. Hughson, Health effects of indoor fungal bioaerosol exposure, Appl. Occup. Environ. Hyg., 2003, 18, 535–544.

    Article  Google Scholar 

  4. J. D. Spengler, J. M. Samet and J. F. McCarthy, Indoor Air Quality Handbook, McGraw-Hill, 2001.

    Google Scholar 

  5. L. S. Ruzer and N. H. Harley, Aerosols Handbook: Measurement, Dosimetry, and Health Effects, CRC Press, 2012.

    Book  Google Scholar 

  6. K.-P. Yu, Y.-T. Huang, S.-C. Yang, The antifungal efficacy of nano-metals supported TiO2 and ozone on the resistant Aspergillus niger spore, J. Hazard. Mater., 2013, 261, 155–162.

    Article  CAS  Google Scholar 

  7. A. Rincon and C. Pulgarin, Photocatalytical inactivation of E. coli: effect of (continuous-intermittent) light intensity and of (suspended-fixed) TiO2 concentration, Appl. Catal., B, 2003, 44, 263–284.

    Article  CAS  Google Scholar 

  8. L. Rizzello, R. Cingolani and P. P. Pompa, Nanotechnology tools for antibacterial materials, Nanomedicine, 2013, 8, 807–821.

    Article  CAS  Google Scholar 

  9. L. Visai, L. De Nardo, C. Punta, L. Melone, A. Cigada, M. Imbriani and C. R. Arciola, Titanium oxide antibacterial surfaces in biomedical devices, Int. J. Artif. Organs, 2011, 34, 929.

    Article  CAS  Google Scholar 

  10. Y. Wei, S. Chen, B. Kowalczyk, S. Huda, T. P. Gray and B. A. Grzybowski, Synthesis of stable, low-dispersity copper nanoparticles and nanorods and their antifungal and catalytic properties, J. Phys. Chem. C, 2010, 114, 15612–15616.

    Article  CAS  Google Scholar 

  11. J. Gamage and Z. Zhang, Applications of Photocatalytic Disinfection, Int. J. Photoenergy, 2010, 2010, 1–11.

    Article  Google Scholar 

  12. K.-P. Yu, G. W.-M. Lee, S.-Y. Lin and C. P. Huang, Removal of bioaerosols by the combination of a photocatalytic filter and negative air ions, J. Aerosol Sci., 2008, 79, 377–392.

    Article  Google Scholar 

  13. T. Matsunaga, R. Tomoda, T. Nakajima and H. Wake, Photoelectrochemical sterilization of microbial cells by semiconductor powders, FEMS Microbiol. Lett., 1985, 29, 211–214.

    Article  CAS  Google Scholar 

  14. J. C. Ireland, P. Klostermann, E. W. Rice and R. M. Clark, Inactivation of Escherichia coli by Titanium Dioxide Photocatalytic Oxidation, Appl. Environ. Microbiol., 1993, 59, 1668–1670.

    Article  CAS  Google Scholar 

  15. W. A. Jacoby, P. C. Maness, E. J. Wolfrum, D. M. Blake and J. A. Fennell, Mineralization of Bacterial Cell Mass on a Photocatalytic Surface in Air, Environ. Sci. Technol., 1998, 32, 2650–2653.

    Article  CAS  Google Scholar 

  16. K. Sunada, Y. Kikuchi, K. Hashimoto and A. Fujishima, Bactericidal and detoxification effects of TiO2 thin film photocatalysts, Environ. Sci. Technol., 1998, 32, 726–728.

    Article  CAS  Google Scholar 

  17. P.-C. Maness, S. Smolinski, D. M. Blake, Z. Huang, E. J. Wolfrum and W. A. Jacoby, Bactericidal Activity of Photocatalytic TiO2 Reaction: toward an Understanding of Its Killing Mechanism, Appl. Environ. Microbiol., 1999, 65, 4094–4098.

    Article  CAS  Google Scholar 

  18. E. J. Wolfrum, J. Huang, D. M. Blake, P.-C. Maness, Z. Huang, J. Fiest and W. A. Jacoby, Photocatalytic Oxidation of Bacteria, Bacterial and Fungal Spores, and Model Biofilm Components to Carbon Dioxide on Titanium Dioxide-Coated Surfaces, Environ. Sci. Technol., 2002, 36, 3412–3419.

    Article  CAS  Google Scholar 

  19. C.-S. Li, C.-C. Tseng, H.-H. Lai, C.-W. Chang, Ultraviolet Germicidal Irradiation and Titanium Dioxide Photocatalyst for Controlling Legionella pneumophila, Aerosol Sci. Technol., 2003, 37, 961–966.

    Article  CAS  Google Scholar 

  20. C.-Y. Lin, C.-S. Li, Inactivation of Microorganisms on the Photocatalytic Surfaces in Air, Aerosol Sci. Technol., 2003, 37, 939–946.

    Article  CAS  Google Scholar 

  21. M. Cho, H. Chung, W. Choi and J. Yoon, Linear correlation between inactivation of E. coli and OH radical concentration in TiO2 photocatalytic disinfection, Water Res., 2004, 38, 1069–1077.

    Article  CAS  Google Scholar 

  22. M. Cho, H. Chung, W. Choi and J. Yoon, Different Inactivation Behaviors of MS-2 Phage and Escherichia coli in TiO2 Photocatalytic Disinfection, Appl. Environ. Microbiol., 2005, 71, 270–275.

    Article  CAS  Google Scholar 

  23. M. Paschoalino and W. Jardim, Indoor air disinfection using a polyester supported TiO2 photo-reactor, Indoor Air, 2008, 18, 473–479.

    Article  CAS  Google Scholar 

  24. F. Chen, X. Yang and Q. Wu, Antifungal capability of TiO2 coated film on moist wood, Build. Environ., 2009, 44, 1088–1093.

    Article  Google Scholar 

  25. F. Chen, X. Yang and Q. Wu, Photocatalytic oxidation of Escherichia coli, Aspergillus niger, and formaldehyde under different ultraviolet irradiation conditions, Environ. Sci. Technol., 2009, 43, 4606–4611.

    Article  CAS  Google Scholar 

  26. P. Foegeding, Ozone inactivation of Bacillus and Clostridium spore populations and the importance of the spore coat to resistance, Food Microbiol., 1985, 2, 123–134.

    Article  CAS  Google Scholar 

  27. L. Restaino, E. W. Frampton, J. B. Hemphill and P. Palnikar, Efficacy of ozonated water against various food-related microorganisms, Appl. Environ. Microbiol., 1995, 61, 3471–3475.

    Article  CAS  Google Scholar 

  28. V. Camel and A. Bermond, The use of ozone and associated oxidation processes in drinking water treatment, Water Res., 1998, 32, 3208–3222.

    Article  CAS  Google Scholar 

  29. M. F. Boeniger, Use of ozone generating devices to improve indoor air quality, Am. Ind. Hyg. Assoc., 1995, 56, 590–598.

    Article  CAS  Google Scholar 

  30. W. J. Kowalski, Aerobiological Engineering Handbook, McGraw-Hill, 2006.

    Google Scholar 

  31. K.-P. Yu, G. W. M. Lee, Decomposition of gas-phase toluene by the combination of ozone and photocatalytic oxidation process (TiO2/UV, TiO2/UV/O3, and UV/O3), Appl. Catal., B, 2007, 75, 29–38.

    Article  CAS  Google Scholar 

  32. C. McCullagh, J. M. C. Robertson, D. W. Bahnemann, P. K. J. Robertson, The application of TiO2 photocatalysis for disinfection of water contaminated with pathogenic micro-organisms: a review, Res. Chem. Intermed., 2007, 33, 359–375.

    Article  CAS  Google Scholar 

  33. L. W. Durrell and L. M. Shields, Fungi Isolated in Culture from Soils of the Nevada Test Site, Mycologia, 1960, 52, 636–641.

    Article  Google Scholar 

  34. M. Anpo and M. Takeuchi, The design and development of highly reactive titanium oxide photocatalysts operating under visible light irradiation, J. Catal., 2003, 216, 505–516.

    Article  CAS  Google Scholar 

  35. S. Ikeda, N. Sugiyama, B. Pal, G. Marcí, L. Palmisano, H. Noguchi, K. Uosaki and B. Ohtani, Photocatalytic activity of transition-metal-loaded titanium(IV) oxide powders suspended in aqueous solutions: Correlation with electron–hole recombination kinetics, Phys. Chem. Chem. Phys., 2001, 3, 267–273.

    Article  CAS  Google Scholar 

  36. R. M. Maier, I. L. Pepper and C. P. Gerba, Environmental Microbiology, Academic press, 2nd edn, 2009.

    Book  Google Scholar 

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Authors and Affiliations

  1. Institute of Environmental and Occupational Health Sciences, National Yang-Ming University, No. 155, Sec. 2, Linong Street, Taipei, 11221, Taiwan

    Jia-You Gong, Yen-Chi Chen, Yi-Ting Huang, Ming-Chien Tsai & Kuo-Pin Yu

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  1. Jia-You Gong
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  2. Yen-Chi Chen
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Correspondence to Kuo-Pin Yu.

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Gong, JY., Chen, YC., Huang, YT. et al. For the inactivation of mold spores by UVC irradiation, with ozone acting as a promoter, TiO2 nanoparticles may act better as a “sun block” than as a photocatalytic disinfectant. Photochem Photobiol Sci 13, 1305–1310 (2014). https://doi.org/10.1039/c4pp00054d

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