Study on Interaction of Y~(3+) and Bovine Serum Albumin by Spectrometry

The interaction between rare earth ion Y3+ and bovine serum albumin(BSA) was studied by fluorescence spectrum and ultraviolet-visible absorption spectrometry.It was shown that Y3+ has a quite strong effect to quench the fluorescence launching and enhance the UV absorption spectra of BSA.The maximum emission peak of BSA shifted to short wave by 20～25 nm.After the fluorescence quenching date was analyzed by Stern-Volmer equation,the results indicated that the reaction between bovine serum albumin and Y3+ generated the new complex-system.The quenching belonged to static fluorescence quenching,with non-radiation energy transfer happening within single molecule.The binding constants(KA) and thermodynamics parameters(ΔΗ,ΔS,ΔG) were calculated according to equation of fluorescence spectrometry at different temperatures.Based on thermodynamic data,the main reaction between Y3+ and BSA was van der Waals force and hydrogen bond,but electrostatic force can not be ignored.The effect of rare earth ion Y3+ on the conformation of BSA was researched by synchronous fluorescence spectrometry.