Spectroscopic investigation on the binding of antineoplastic drug oxaliplatin to human serum albumin and molecular modeling

This study was designed to examine the interaction of oxaliplatin with human serum albumin (HSA) under physiological conditions by using fluorescence, absorption, FT-IR and circular dichroism (CD) spectroscopic techniques in combination with molecular docking study. Spectroscopic analysis of the emission quenching at different temperatures has revealed that the quenching mechanism of oxaliplatin with HSA was static quenching mechanism. The value of 1.64 nm for the distance r between the donor (HSA) and acceptor (oxaliplatin) was derived from the fluorescence resonance energy transfer. From the CD and FT-IR results, it was apparent that the interaction of oxaliplatin with HSA caused a conformational change of the protein. Molecular docking study showed that oxaliplatin bind to residues located in subdomain IIA of HSA. The effect of metal ions and amino acids on the binding constant of HSA–oxaliplatin complex was also discussed.