Lu Xiu-Min, Chen De-Jun, Wang Gong-Ke, Yang Hai-Yan, Lu Yan
College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007, China.
Guang Pu Xue Yu Guang Pu Fen Xi. 2009 Jan;29(1):236-9.
The interaction between norfloxacin (NRF) and ovalbumin (OVA) was studied by fluorescence and absorption spectroscopy. The binding constants and the binding sites were measured by fluorescence quenching method. It was found that the emission peak of OVA was positioned at 338 nm. When the norfloxacin was added into OVA solution gradually, the intensity of 338 nm emission peak of OVA decreased obviously and moved towards long wavelength. The experiment demonstrated that the higher the temperature, the lower the slopes of quenching curves of OVA in the presence of different amounts of NRF. It was confirmed that the combination of NRF with OVA is a single static quenching process. With the increase in the pH of the solution, the quenching efficiency decreased in the binding. From thermodynamic parameters, it can be judged that the binding power between OVA and NRF is electrostatic effect and H-bond formation. The UV-Vis absorption spectra of OVA in the presence of NRF show that the conformation of OVA changed.
通过荧光光谱和吸收光谱研究了诺氟沙星（NRF）与卵清蛋白（OVA）之间的相互作用。采用荧光猝灭法测定了结合常数和结合位点。发现OVA的发射峰位于338nm处。当将诺氟沙星逐渐加入OVA溶液中时，OVA在338nm处的发射峰强度明显降低并向长波长方向移动。实验表明，温度越高，在不同量NRF存在下OVA的猝灭曲线斜率越低。证实NRF与OVA的结合是单一的静态猝灭过程。随着溶液pH值的升高，结合中的猝灭效率降低。从热力学参数可以判断，OVA与NRF之间的结合力是静电作用和氢键形成。NRF存在下OVA的紫外可见吸收光谱表明OVA的构象发生了变化。
