二氧化鈦光觸媒主要是藉由紫外光照射後所產生的氧化還原反應來殺死細菌。最近有研究證明，某些改良過的二氧化鈦光觸媒薄膜與粉末在經過可見光的照射後能產生殺菌能力。然而這些可見光光觸媒的殺菌效果仍沒有最佳化，且這些可見光光觸媒的殺菌機制也仍需做進一步的研究。在我們的研究中發現，經過可見光照射的可見光光觸媒粉末(VLPs)不僅可以殺死金黃色葡萄球菌、化膿性鍊球菌與多重抗藥性鮑式不動桿菌，造成這些細菌的細胞膜不完整，而且還可以破壞plasmid DNA，並造成DNA的突變。除此之外，我們還發現這些經過可見光照射的VLPs就算不能殺死細菌，也能讓細菌受傷，並進而讓巨噬細胞清除這些細菌的效率更好。這些研究證實了VLPs在將來也許能夠成為殺菌與清除DNA汙染的另一種替代方法，除了可能能應用於環境衛生上外，或許還可以應用於醫學上。

Photo-excited titanium dioxide (TiO2) substrates are primarily induced by UV-light irradiation to exert their bactericidal activities through oxidation and reduction. Recently, some modified TiO2 films and powders were proved to have equally potent antimicrobial activities against bacteria under visible-light illumination. However their bactericidal activity remains to be further optimized and their bactericidal mechanism remains to be further studied. In this study, we found that not only bacteria can be killed by visible-light illuminated visible-light photocatalysts nano-particles (VLPs) in vitro experiments, but plasmid DNA also can be damaged and mutated. Furthermore, visible-light illuminated VLPs can injure bacteria and make them vulnerable for the clearance by phagocytes. These findings suggest that VLPs may be an alternative approach to develop bactericidal strategies in public environmental sanitation and medical therapy in the future.

目錄


中文摘要…………………………………………………………………...………….2

Abstract………………………………………………………………………………..3

I.緒論…………………………………………………………………………………7
A.前言………………………………………………………………………….7
B.光觸媒……………………………………………………………………….8
C.研究動機與原理闡述……………………………………………………...10

II.材料與方法………………………………………………………………………12
A.可見光光觸媒粉末………………………………………………………...12
B.亞甲基藍溶液……………………………………………………………...12
C.細胞株…………………………………………………………………...…12
D.細菌珠……………………………………………………………………...12
E.細胞培養、繼代、保存與解凍………………………………………….…13
F.細菌的培養與保存……………………………………………………...…14
G.光源設備………………………………………………………………...…15
H.亞甲基藍脫色實驗……………………………………………………...…15
I.體外的可見光光觸媒粉末的殺菌實驗………………………………...…15
J.巨噬細胞J774A•1消化細菌能力之分析實驗……………………….…15
K.製備勝任細胞 (competent cell)..……………………………………….....16
L.pBluescript SK+ plasmid (簡稱SK+)…………………………………...…16
M.轉形作用………………………………………………………………...…16
N.萃取質體………………………………………………………………...…17
O.X-gal培養皿的製備…………………………………………………….…17
P.可見光光觸媒粉末破壞DNA實驗…………………………………….…18

III.實驗結果……………………………………………………………………….…19
A.可見光光觸媒粉末殺菌能力及原因之探討………………………………..…19
一、各種可見光光觸媒粉末對亞甲基藍的脫色能力……………………..…19
二、比較C200與Pt•TiO2可見光光觸媒粉末的殺菌能力…………………19
三、各種光照強度與不同照光時間對Pt•TiO2可見光光觸媒粉末殺菌效果的影響…………………………………………………………………..…20
四、Pt•TiO2可見光光觸媒粉末對各種病原菌的殺菌能力.......……………21
五、巨噬細胞J774A•1對Pt•TiO2可見光光觸媒粉末處理過的細菌之消化能力……………………………………………………………………..…22

B.Pt•TiO2可見光光觸媒粉末破壞DNA能力之探討…………………………23
七、Pt•TiO2可見光光觸媒粉末對plasmid DNA的影響……………………23
八、Pt•TiO2可見光光觸媒粉末是否能造成plasmid DNA突變……..….…23

IV. 討論…………………………………………………………………………...…24

V. 實驗圖表……………………………………………………………………….…38

VI. 參考文獻……………………………………………………………………...…35

VII. 附錄………………………………………………………………………….…37
A.C200可見光光觸媒粉末對老鼠體內HeLa細胞的影響。……………..…37
B.C200可見光光觸媒粉末對亞甲基藍的脫色實驗。………………………38





圖目錄

圖一、各種可見光光觸媒粉末對亞甲基藍的脫色能力。………………………..…30
圖二、比較C200與Pt•TiO2可見光光觸媒粉末的殺菌能力。………………………………………………………………….……………...…31
圖三、各種光照強度與不同照光時間對Pt•TiO2可見光光觸媒粉末殺菌效果的影響。…………………………………………………………………………………32
圖四、Pt•TiO2可見光光觸媒粉末對各種病原菌的殺菌能力。………………………………………………………………………...……….…33
圖五、巨噬細胞J774A•1對Pt•TiO2可見光光觸媒粉末處理過的細菌之消化能力。……………………………………………………………………………………35
圖六、Pt•TiO2可見光光觸媒粉末對plasmid DNA的影響。……………………. ……………………………………………………………36
圖七、Pt•TiO2可見光光觸媒粉末是否能造成plasmid DNA突變。……………………………………………………………………………….…37

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