Intermolecular interaction of nickel (ii) phthalocyanine tetrasulfonic acid tetrasodium salt with bovine serum albumin: A multi-technique study

ABSTRACT

The interaction of nickel (II) phthalocyanine tetrasulfonic acid tetrasodium salt with bovine serum albumin (BSA) has been investigated by combination of fluorescence, UV-vis absorption, Fourier transform infrared (FT-IR), and circular dichorism (CD) spectroscopies as well as through molecular docking. Fluorescence quenching and absorption spectra were investigated as a mean for estimating the binding parameters. Analysis of fluorescence quenching data at different temperatures was performed in order to specify the thermodynamics parameters for interactions of phthalocyanine complex with BSA. According to experimental data it was suggested that phthalocyanine had a significant binding affinity to BSA and the process was entropy driven. Based on the results of molecular docking it was indicated that the main active binding site for this phthalocyanine complex is site I in subdomain IIA of BSA. The results provide useful information for understanding the binding mechanism of anticancer drug-albumin and gives insight into the biological activity and metabolism of the drug in blood.

KEYWORDS:

• Phthalocyanine
• serum albumin
• fluorescence quenching
• optical absorption spectroscopy
• molecular docking

Acknowledgment

The authors gratefully acknowledge the Research Council of University of Guilan for supporting this work.