家用日光燈照射二氧化鈦塗膜的殺菌作用

Bacterial Inactivation By Titanium Oxide Contained Coating Under Household Fluorescent Light Irradiation

高維鑫(Wei-Hsing Kao)

指導教授 ： 許垤棊

大同大學/工程學院/生物工程學系所/碩士(2005年)

摘要

在淨化水和空氣方面，使用二氧化鈦光觸媒這個材料是個值得注意且可利用的方法。當二氧化鈦表面受波長低於385nm以下的紫外光照射時會產生強大的氧化能力。在有水和氧存在的條件下，二氧化鈦可藉由紫外線(UVA)照射產生高氧化力的氫氧自由基和超氧自由基。這些自由基可攻擊細菌，造成細菌的死亡，因此可防止細菌的污染。本實驗採用商業用二氧化鈦塗膜在家用日光燈照射下，評估光反應殺菌的效果。腸球菌(E. faecium)、金黃葡萄球菌(S. aureus) 、大腸菌(E. coli)、 綠膿菌(. aeruginosa) 、白色念珠菌(C. albicans) 用於本實驗，將這幾種病原菌懸浮於含有4% (w/v)甘油的磷酸緩衝生理食鹽水中，然後塗佈於二氧化鈦塗膜上。在照射90分鐘期間，細菌存活數的衰減符合一級動力學。以小時－1記錄這些菌株的反應速率常數k值(空白試驗/TiO2)分別是0.193/1.760, 1.407/1.973, 0.309/2.613, 0.847/2.573 以及1.220/2.107。二氧化鈦顆粒大小對殺菌效果亦有影響。二氧化鈦顆粒越小，對於腸球菌的殺菌效果越好。最後，並且比較日光燈和紫外燈照射下，二氧化鈦塗膜的殺菌效果。

關鍵字

殺菌效果、光觸媒反應、二氧化鈦

並列摘要

Titanium dioxide (TiO2) photocatalysts have attracted great attention as alternative concept to aid in the purification of water and air. TiO2 photocatalysts generate free radicals when illuminated by lights having wavelength shorter than 385 nm. These radicals are able to attack bacteria, and may therefore be efficacious in reducing bacterial pollution. In this study, a highly sensitive method for the evaluation of the photoinduced disinfection of a commercial TiO2-contained coating under a household fluorescent light irradiation was developed. Enterococcus faecium, Staphylococcus aureus, Pseudomonas aeruginosa, E.coli, and Candida albicans were suspended in 4% (w/v) glycerol in PBS and smeared on a surface containing TiO2. During irradiation for up to 90 min the decay of microbial viability nearly followed the first order kinetics. The rate constant k (blank/TiO2) in h－1 for these strains were 0.193/1.760, 1.407/1.973, 0.309/2.613, 0.847/2.573 and 1.220/2.107, respectively. The bactericidal effect of TiO2 in different particle size was also investigated. As the TiO2 particle decreased in size, bactericidal effect increased. Furthermore, the TiO2 coatings irradiated by the household fluorescent light and UVA were compared in bactericidal efficacy against S. aureus.

並列關鍵字

Bactericidal efficacy ； Photocatalysis ； Titanium

參考文獻

Amézaga-Madrid, P., Nevárez-Moorillón, G.V., Orrantia-Borunda, E. and Miki-Yoshida, M. (2002) Photoinduced bactericidal activity against Pseudomonas aeruginosa by TiO2 based thin film. FEMS Microbiol. Lett. 211, 183 188.

Blake, D. M., Maness, P.- C., Huang, Z., Wolfrum, E. J. and Huang, J. (1999) Application of the photocatalytic chemistry of titanium dioxide to disinfection and the killing of cancer cells. Separation and Purification Methods, 28(1), 1-50.

Bock, C., Dittmar, H., Gemeinhardt, H., Bauer, E., Greulich, K.O.,(1998) Comet assay detects cold repair of UV-A damages in human B-lymphoblast cell line.Mutat. Res. 408,111-120

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

Clovis, A., David, B. and Lisa, A. (2000) Photocatalytic inhibition of algae growth using TiO2, WO3, and cocatalysts modifications. Environ. Sci.Technol. 34, 4754-4758.