活性橙122与腐殖酸相互作用的研究

Studies on the Interaction between Reactive Orange 122 and Humic Acid

采用荧光光谱和紫外-可见吸收光谱研究了活性橙122 (RO122)与腐殖酸(HA)的相互作用。实验结果表明,RO122对HA的荧光猝灭属于静态猝灭;根据修正的Stern-Volmer方程计算了不同温度下两者的结合常数,并结合Van't Hoff方程计算出相应的热力学参数,计算结果ΔH=-52.250 kJ/mol<0、ΔS=-82.511 J·mol^(-1)·K^(-1)<0,表明RO122与HA之间主要依靠氢键和范德华力结合;根据紫外吸收光谱和三维荧光光谱可知RO122与HA的相互作用可使HA的共轭度降低。

The interaction between reactive orange 122 and humic acid (HA) was investigated by fluorescence and UV-Vis absorption spectroscopy.All the experimental evidences show that the mechanism of HA fluorescence quench by reactive orange 122 is static quenching.The binding constants at different temperatures were calculated by the modified Stern-Volmer equation,the calculation result of enthalpy change (ΔH) is-52.250 kJ/mol<0,and the calculation result of entropy change (ΔS) is-82.511 J ·moL^-1·K^-1<0,indicating that hydrogen bonding and Van der Waals force play a dominant role in the stability of the reactive orange 122/HA complex.According to UV-Vis absorption and fluorescence spectra,the conjugation degree of HA can be reduced by the interaction between reactive orange 122 and HA.