期刊
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
卷 25, 期 21, 页码 14836-14847出版社
ROYAL SOC CHEMISTRY
DOI: 10.1039/d3cp01597a
关键词
-
X-ray photoelectron spectroscopy (XPS) was used to study the mechanism of high radio-sensitisation in living cells with brominated genomic DNA. The bromine atom reduced the energy gap between the valence and conduction states, facilitating electron transfer and increasing the probability of reaction with low energy electrons. This leads to DNA damage and cytotoxic effects.
To understand the mechanism underlying the high radio-sensitisation of living cells possessing brominated genomic DNA, X-ray photoelectron spectroscopy (XPS) using synchrotron X-rays with energies of 2000 or 2500 eV was used to study brominated and nonbrominated nucleobases, nucleosides and nucleotides. The bromine atom significantly reduced the energy gap between the valence and conduction states, although the core level states were not greatly affected. This finding was supported by quantum chemical calculation for the nucleobases and nucleosides. Our findings strongly indicate that the energy gaps between the valence and conduction levels of the molecules are significantly reduced by bromination. Furthermore, the brominated molecules are more likely to produce inelastic scattering low energy electrons upon exposure to 2000 or 3000 eV X-rays. This modification of electronic properties around the brominated group may both facilitate electron transfer to the brominated site in DNA and increase the probability of reaction with low energy electrons. These processes can induce DNA damage, presumably resulting in debromination of the uracil moiety and a subsequent cytotoxic effect.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据