Investigation of the Interaction Between Human Serum Albumin and Antitumor Palladium(II) Complex Containing 1,10-Phenanthroline and Dithiocarbamate Ligands

Abstract

The interaction between [Pd(But-dtc)(phen)]NO3 (where But-dtc = butyldithiocarbamate and phen = 1,10-phenanthroline) with HSA (Human Serum Albumin) was investigated by applying fluorescence, UV–Vis and circular dichroism techniques under physiological conditions. The results of fluorescence spectra indicated that the Pd(II) complex could effectively quench the fluorescence intensity of HSA molecules via static mechanism. The number of binding sites and binding constant of HSA–Pd(II) complex were calculated. Analysis of absorption titration data on the interaction between Pd(II) complex and HSA revealed the formation of HSA–Pd(II) complex with high-binding affinity. Thermodynamic parameters indicated that hydrophobic forces play a major role in this interaction. Furthermore, CD measurements were taken to explore changes in HSA secondary structure induced by the Pd(II) complex.