Voltammetric and spectroscopic investigations on the mechanism of interaction of buzepide methiodide with protein

Adsorption or immobilization of proteins on solid surfaces promotes the biological responses to materials. Using immobilization technique, we have prepared human serum albumin (HSA) modified glassy carbon electrode (GCE) and employed it to probe the mode of interaction between antidepressant drug, buzepide methiodide (BZP) and HSA. At HSA modified GCE, the peak potential of BZP appeared at more positive potential compared to that at bare electrode thereby indicating the hydrophobic mode of interaction between BZP and HSA. Peak currents of BZP decreased upon the addition of HSA at bare GCE with positive shift in peak potential. Further, no new peaks were observed in presence of HSA. From electrochemical data, the binding constant and binding ratio between HSA and BZP were calculated to be 9.33 × 106 M−1 and 1:2, respectively. FT-IR and circular dichroism (CD) studies revealed that the secondary structure of protein was perturbed upon interaction with BZP.