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运用循环伏安法，紫外光谱和拉曼光谱等方法研究了Ｅｕ３＋、Ｃｅ３＋、Ｅｒ３＋、Ｓｍ３＋、Ｔｂ３＋、Ｌａ３＋、Ｎｄ３＋等稀土金属离子与ＤＮＡ（小牛胸腺）的相互作用．Ｃｅ３＋与ＤＮＡ作用后，Ｃｅ３＋的ＣＶ曲线的峰电流密度明显降低，且氧化峰降低的程度大于还原峰；Ｃｅ３＋的差示ＵＶ曲线呈减色效应，且在２７２ｎｍ处出现新峰；ＤＮＡ的差示ＵＶ曲线呈增色效应；ＤＮＡ的拉曼谱线中８１４ｃｍ－１处的峰消失，表明铈离子对ＤＮＡ的磷酸二酯键具有切断作用．Ｅｕ３＋和ＤＮＡ作用后，Ｅｕ３＋的ＣＶ曲线的峰电流密度仅略有减少，氧化峰和还原峰电流密度降低程度相近，且ＤＮＡ的差示ＵＶ曲线呈减色效应．可能是Ｅｕ３＋和ＤＮＡ磷酸基之间的静电作用使碱基面进一步堆积所致．Ｅｒ３＋、Ｓｍ３＋、Ｔｂ３＋、Ｌａ３＋、Ｎｄ３＋也都能与ＤＮＡ发生作用，但是，与ＤＮＡ作用的能力不同．其中Ｃｅ３＋离子对ＤＮＡ作用最强，且对ＤＮＡ主链磷酸二酯键具有切断功能，Ｃｅ３＋离子有可能成为催化水解切断ＤＮＡ的“分子剪刀”
The interaction of rare earth metal ions such as Eu3 +, Ce3 +, Er3 +, Sm3 +, Tb3 +, La3 + and Nd3 + with DNA (calf thymus) was studied by cyclic voltammetry, UV and Raman spectroscopy. After the interaction between Ce3 + and DNA, the peak current density of the CV curve of Ce3 + decreased significantly and the oxidation peak decreased more than that of the reduction peak. The differential UV curve of Ce3 + showed a color decreasing effect with a new peak at 272 nm. The UV curve shows an enhancement effect; the peak at 814 cm-1 in the Raman spectrum of DNA disappears, indicating that cerium ions have a cleavage effect on the DNA phosphodiester bond. After Eu3 + and DNA interaction, the peak current density of Eu3 + in CV curve decreased only slightly, and the reduction of oxidation peak and reduction peak current density was similar, and the differential UV curve of DNA showed a subtractive effect. It is possible that the electrostatic interactions between Eu3 + and DNA phosphate groups cause the base surface to further accumulate. Er3 +, Sm3 +, Tb3 +, La3 +, and Nd3 + all also interact with DNA, but their ability to interact with DNA is different. Among them, Ce3 + ion has the strongest effect on DNA, and has the function of cutting off the DNA backbone phosphodiester bond, and Ce3 + ions may become the “molecular scissors” that catalyze the hydrolysis and cleavage of DNA.