Interaction between silicotungstic acid,silicon tungsten-cobalt heteropoly acid and bovine serum albumin by fluorescence spectrometry

The interactions of bovine serum albumin(BSA)with silicotungstic acid(SiW)and silicon tungsten-cobalt heteropoly acid (SiWCo) were studied by fluorescence and ultraviolet absorption spectroscopy.The fluorescence quenching of BSA with SiW and SiWCo was static quenching,and the binding constants at 298 K and 310 K were 4.94×10⁴,6.06×10⁴(298 K),4.33×10⁴,5.86×10⁴(310K),respectively.The number of binding site (n) was 1.The interaction of BSA with SiW and SiWCo was electrostatic force based on the thermodynamic parameters calculated at 298 K and 310 K.The conformation of BSA impacted by SiW and SiWCo was also discussed by synchronous fluorescence.The results showed that both SiW and SiWCo interacted with BSA,without changing its conformation,and the interaction between SiWCo and BSA was more active than that of SiW.