Pd(II) Complex Based on the Propylenebis (Dithiocarbamate) Bridging Ligand: Synthesis, Characterization, Antioxidant Activity and Investigation on the Interaction with Human Serum Albumin

A new bridging dithiocarbamate ligand and its Pd(II) metal ion complex (Fig. 1) was synthesizedand characterized [1]. The in vitro antioxidant activity of the prepared complex wasevaluated as radical scavengers against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH.). Theresults showed that this complex has a good antioxidant potential. The binding studies of thiscomplexwith the model protein, human serum albumin (HSA), were investigated by employingbiophysical techniques as well as computational modeling.The experimental resultsshowed that the complex interacted with HSA by moderate binding affinity. Binding of complexto HSA caused strong fluorescence quenching of protein through static quenching mechanism.In the studied system, hydrogen bonds and Van der Waals forces were the major stabilizingforces in the drug-protein complex formation. Protein–ligand docking analysis confirmedthat the Pd(II) complex bind to residues located in the subdomain IIA of HSA. Allthese experimental and computational results suggest that HSA may act as a carrier proteinfor the complex to deliver it to the target molecules.