Study on the interaction of N1-(1-phenylethyl) propane-1,2-diamine Nickel(II) complex and bovine serum albumin by fluorescence spectra

The binding reaction of the N¹-(1-phenylethyi) propane-1,2-diamine nickel(II) complex with bovine serum albumin(BSA) was studied by fluorescence spectroscopy under the simulative physiological conditions. The experimental results show that the complex had a quite strong ability to quench the fluorescence from BSA and the quenching mechanism of this complex to bovine serum albumin was static quenching. The binding constants were 4.92×10⁶ and 1.35×10⁶ L-mol¹ at 293K and 303K with one binding site, respectively. The type of bonding forces was estimated by the calculation of thermodynamic parameters of the reaction of the complex with BSA at different temperatures, and the result showed that H-bond and Van der Waals are two main reactions between complex and BSA. The effect of the complex on the BSA conformation was also studied by using synchronous fluorescence spectrum.