左氧氟沙星与小牛胸腺DNA相互作用的荧光光谱法研究

Interaction of Levofloxacin with Calf Thymus DNA by Fluorescence Spectra

采用荧光光谱法研究了左氧氟沙星和小牛胸腺DNA之间的相互作用。以Stern-Volmer方程、双倒数曲线及Scatchard方程等方法处理实验数据,并通过用紫外光谱、离子强度的影响、单双链DNA作用比较和I-猝灭等条件,研究了左氧氟沙星与DNA间的相互作用模式。结果表明,小牛胸腺DNA对左氧氟沙星的荧光具有强烈的猝灭作用,作用常数为5.23×103L·mol-,结合位点数为2.6,两者之间可能是一种沟槽作用模式。

ZHENG Zhao-Hua, YE Bao-Fen, DUYing-Xiang, CHEN Yu-Ying (Dept. ofAnalytical Chemistry, China Pharmaceutical University, Nanjing 210009) A B S T R A C T : The interaction of levofloxacin with calf thymus DNA was investigated with fluorescence spectrophotometry. The experiment data were plotted by Stern-Volmer equation, double reciprocal equation and Scatchard equation, respectively.The interaction modewasdiscussed with UV method,theinfluence ofion strength, the comparison of single and doublestranded DNA bound to levofloxacin and I- quenching effect. Theresultsshowed that the addition of calf thymus DNA to levofloxacin solution resulted in a strong fluorescence quenching. The quenching constant Kqwas 5.23× 103 L·mol- and the binding sitenumber in DNA base pairs n was 2.6.The interaction mode between levofloxacin and calf 1 thymus DNA might bea kind of groovebinding.