Visible light-induced plasmid DNA damage catalyzed by a CdSe/ZnS-photosensitized nano-TiO2 film.
Visible light-induced plasmid DNA damage catalyzed by a CdSe/ZnS-photosensitized nano-TiO2 film.
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DOI：
10.1021/es800668g
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发表时间：
2008-06
影响因子：
11.4
通讯作者：
Xin-Cheng Shen;Zhiling Zhang;Bo Zhou;Jun Peng;Min Xie;Min Zhang;D. Pang
中科院分区：
文献类型：
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作者：
Xin-Cheng Shen;Zhiling Zhang;Bo Zhou;Jun Peng;Min Xie;Min Zhang;D. Pang
改性二氧化钛可见光催化降解环境污染物在污染控制和管理中受到了广泛的关注。核酸的降解对病毒等生物污染物具有重要意义。利用原子力显微镜(AFM)和琼脂糖凝胶电泳法研究了CdSe/ZnS光敏纳米TiO2膜(QDS-TiO2膜)对可见光诱导的DNA损伤。在可见光照射下，超螺旋pUC18 DNA被Qds-TiO2膜破坏为缺口环状和线状构象。损伤DNA的不同构象百分率随光照时间的延长而变化。根据原子力显微镜的结果，建立了计算超螺旋DNA数量的统计规则，以评价Qds-TiO2光催化活性。量子点-二氧化钛薄膜对可见光诱导的质粒DNA损伤符合零级动力学特征，其速率常数(K)为3.5×10~(-11)M×S(-1)。在一定的光照时间下，量子点-二氧化钛薄膜催化损伤的超螺旋DNA的量是恒定的。
Visible light-induced photocatalytic degradation of environmental pollutants with improved TiO2 has attracted much attention in pollution control and management. The degradation of nucleic acids is of great significance for biological contaminants such as viruses. In the presentwork, visible light-induced plasmid DNA damage catalyzed by a CdSe/ZnS-photosensitized nano-TiO2 film (QDs-TiO2 film) was investigated by atomic force microscopy (AFM) and agarose gel electrophoresis. Illuminated by visible light, the supercoiled pUC18 DNA could be damaged into nicked-circle and linear conformations by the QDs-TiO2 film. The percentage of different conformations of damaged DNA changed with illumination time. A statistical rule for calculating the quantity of supercoiled DNA has been established to evaluate the photocatalytic activity of the QDs-TiO2 film based on AFM results. Visible light-induced plasmid DNA damage catalyzed by the QDs-TiO2 film is characteristic of zero-order kinetics and the rate constant (k) is 3.5 x 10(-11) M x s(-1). Given an illumination time, the quantity of damaged supercoiled DNA catalyzed by the QDs-TiO2 film is constant.