The binding properties of photosensitizer methylene blue to herring sperm DNA: a spectroscopic study.
The binding properties of photosensitizer methylene blue to herring sperm DNA: a spectroscopic study.
复制标题
DOI：
10.1016/j.jphotobiol.2004.03.005
复制
发表时间：
2004-05
期刊：
影响因子：
--
通讯作者：
Lei Z. Zhang;G. Tang
中科院分区：
文献类型：
--
作者：
Lei Z. Zhang;G. Tang
亚甲基蓝（MB）是一种吩噻嗪类光敏剂，在光动力学疗法（PDT）抗癌治疗中具有广阔的应用前景。通过吸收光谱测定、猝灭实验和光漂白过程的解释，研究了亚甲基蓝与鲱鱼精DNA的结合特性。在吸收光谱中观察到MB在DNA含量增加的情况下显着的减色和红移效应。MB的淬灭的DNA碱基遵守Stern-Volmer方程和亚铁氰化物淬灭的MB在DNA的存在和不存在下也被测量作为扩展实验。上述光谱测量结果均符合MB与DNA的嵌入结合模式，其Kb值为1.89× 104 M −1。对MB及其DNA复合物的光漂白过程也进行了研究，结果表明MB及其DNA复合物的光漂白是以不同的机制进行的，活性氧是MB自敏化光氧化的主要原因。
Methylene blue (MB) is a phenothiazinium photosensitizer with promising applications in the photodynamic therapy (PDT) for anticancer treatment. The binding properties of MB to herring sperm DNA have been investigated by the measurements of absorption spectra, quenching experiments and the elucidation of the photobleaching processes. Remarkable hypochromic and bathochromic effects of MB in the presence of increasing amounts of DNA have been observed in the absorption spectra. The quenching of MB by the DNA bases obeys the Stern–Volmer equation and ferrocyanide quenching of MB in the absence and presence of DNA is also measured as extended experiments. Results from the above spectral measurements are all consistent with the intercalative binding mode of MB to DNA with the Kbvalue of 1.89×104M−1. The photobleaching processes of MB and its DNA complex have also been studies, which indicate that the photobleaching of MB and its DNA complex proceeds with different mechanisms and the reactive oxygen species are responsible for the self-sensitized photooxidation of MB.