The Association Interactions Between Tween20?CTAB And Coomassie Brilliant Blue G250

In this paper,the interaction between the anionic dye Coomassie Brilliant Blue G250 and the nonionic surfactant Tween20 and the cationic surfactant CTAB was studied by UV-visible spectroscopy,conductivity method,fluorescent probe method and surface tension method.The UV-visible spectrum of the dye was obtained in the presence or absence of a surfactant,and the interaction between the dye and the surfactant was verified based on the change in the position and intensity of the maximum absorption peak.The interaction of dyes with surfactants has now been widely used in various fields,providing many conveniences for human society.The critical micelle concentration of Tween20 in Coomassie Brilliant Blue G250aqueous solution was obtained according to UV-Vis and fluorescence spectra,and the conductivity of the solution was verified by the conductivity method.The critical micelle concentration of the solution was 5.25×10~-55 mol/L.The micropolarity and related thermodynamic interaction parameters of the solution were calculated by calculation.The SDAI thermodynamic model of interaction between surfactant and dye was used to study the interaction between dye Coomassie Brilliant Blue G250 and Tween20 at different temperatures.It was found that the temperature rise inhibited the interaction between the two and the thermodynamic related parameters of the reaction were obtained.The enthalpy change?H and entropy change?S of the reaction are-5.463 kJ/mol and 61.22 J/mol/K,respectively.In addition,the interaction of Coomassie Brilliant Blue G250 with Tween 20 and CTAB in a mixed surfactant aqueous solution was investigated by surface tension method.According to the measured surface tension of the mixed system,the surface tension isotherm is drawn to obtain the interface properties of the mixed system.The Rubingh model and the Motomura model were used to study the interaction of Coomassie Brilliant Blue G250 with two kinds of mixed surfactants and compared with a single type of surfactant.According to the experimental data,the interfacial properties and micellization parameters of a series of mixed systems such as activity coefficient,interaction parameters and free energy changes were calculated.