| Institution: | 1.Department of Chemistry, College of Sciences,University of Hormozgan,Bandar Abbas,Iran;2.Department of Chemistry,Shiraz University,Shiraz,Iran;3.Department of Chemistry,Razi University,Kermanshah,Iran;4.Organic Colorant Department,Institute for Color Science and Technology,Tehran,Iran;5.Center of Excellence for Color Science and Technology (CECST),Institute for Color Science and Technology,Tehran,Iran |
| Abstract: | A new merocyanine dye was synthesized, and its acidity constant was determined by spectrophotometric and chemometrics methods. The interactions of the new cyanine dye with bovine serum albumin (BSA) have been studied by fluorescence and UV absorption spectroscopy at pH 7.40. A visual color change from red to blue was observed by addition of BSA to aqueous solution of the dye. The quenching constants and binding parameters (binding constants and number of binding sites) were determined at different temperatures. The calculated thermodynamic parameters confirmed that the binding reaction is mainly entropy-driven, whereas electrostatic interaction plays major role in the reaction. The displacement experiment confirmed binding of the dye to the subdomain IIA (site 1) of albumin. Moreover, synchronous fluorescence spectroscopy studies revealed the dye induces some local conformational change in BSA. The binding distance, r, between donor (serum albumin) and acceptor (dye) was obtained according to Förster’s theory. |
