8-羟基脱氧鸟苷与鱼精蛋白相互作用的研究及其分析应用

Study on interaction between 8-hydroxy-2′-deoxyguanosine and protamine sulfate and it′s application

目的:建立一种简便的8-OH-dG检测新方法。方法:在pH8.6的Tris-HCl缓冲液中,8-OH-dG阴离子与鱼精蛋白阳离子作用,形成静态复合物,导致鱼精蛋白的荧光强度减弱。结果:根据F rster非辐射能量转移理论,鱼精蛋白与8-OH-dG结合常数为KA=3.10×104L/mol(t=25℃)。确定供体-受体之间的距离r=3.47 nm和能量转移效率E=0.24。实验表明,8-羟基脱氧鸟苷与鱼精蛋白的作用为静态荧光猝灭过程。方法的检测下限为0.18μg/ml,回归方程为y^=8.7+70X(μg/ml),r=0.9967。结论:该方法快速简便,已成功用于加标样品的分析。

Objective ：To develop a simple and sensitive method for determination of 8 -Hydroxy- 2＇ -deoxyguanosine（8 -OH - dG）. Methods：In the pH 8. 6 Tris - HCl buffer, the fluorescence intensity of protamine sulfate（Ps） was decreased due to formation of ion-association complex of 8 -OH -dG anion with Ps cation. Results：The interaction between 8 -OH -dG and Ps was studied by fluorescence spectroscopy. The result showed that the combination constant was 3.10 ×10^4 L/mol（KA）. The binding distance between 8 - OH - dG and Ps was 3.47 nm and the energy transfer efficiency was 0. 24（E）. It was proved that static quenching exits between 8 -OH -dG and Ps based on Foerster spectroscopy theory for energy transfer, which was linear to the concentration of 8 -OH- dG in the range of 0. 50 - 4. 5μg/ml. The detection limit was 0. 18 i^g/ml,regression equation y=8. 7 ＋70X（txg/ml） ,r =0. 9967. Conclusion ：The proposed method is succeeded in the spiked sample determination with simple characteristics.