α粒子辐照致DNA双链断裂的AFM观测

Atomic force microscopy observation of DNA double strand breaks irradiated with α-particles

在放射生物学中 ,脱氧核糖核酸 (DNA)是电离辐射引致细胞杀伤或转化的主要靶分子 ,研究它的电离辐射损伤具有深远的意义。以此为目的 ,选用LET为 90keV μm的α粒子 ,以不同的剂量对纯化的质粒DNA进行辐照 ,并用原子力显微镜 (AFM)对其所诱发的DNA双链断裂进行了定性观测。同时 。

DNA is the critical target for ionizing-radiation-induced cell killing or transformation in radiobiology. In particular, DNA double strand breaks(DSBs)are considered as the most important molecular damage. It has a far-reaching significance to study DNA damage induced by ionizing radiation. With this purpose, purified plasmid DNA(in aqueous solution) was irradiated with 90keV/μm α-particle produced by a 241Am source at different doses, and atomic force microscopy was used to observe the DNA double strand breaks. In addition, plasmid DNA form have been analyzed by gel electrophoresis technology.