期刊
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
卷 53, 期 16, 页码 6207-6212出版社
AMER CHEMICAL SOC
DOI: 10.1021/jf050783d
关键词
DNA; NFX-Tb3+ complex; fluorimetry; interaction
The fluorescence intensity of the norfloxacin (NFX)-Tb3+ complex enhanced by DNA was studied. Therefore, a sensitive fluorescence method for the determination of DNA was developed. The optimal conditions of the method were as follows: the hexamethylenamine (HMA)-HCl buffer was adopted for adjusting the pH to 6.5 +/- 0.1, the concentrations of NFX and Tb3+ were both fixed in 1.0 x 10(-6) mol L-1, and the excitation and emission wavelengths were selected at 290 and 545 nm, respectively. Under the optimal conditions, the enhanced fluorescence intensity was in proportion to the concentration of DNA in the same range of 5.0 x 10(-9)-1.0 X 10(-6) g mL(-1) for hsDNA and thermally denatured ctDNA. The detection limits (S/N = 3) were 0.9 and 0.6 ng mL(-1), respectively. In addition, the interaction between NFX-Tb3+ and DNA was discussed in detail. The experimental results from UV absorption spectra, fluorescence spectra, and the salt effect study indicated that the interaction between norfloxacin-Tb3+ complex and DNA had at least two different binding modes: the electrostatic binding and the intercalation binding. The mechanism of the fluorescence enhancement effect was also discussed.
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