Affiliations: Laboratory of physical Chemistry, Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran
Note: [] Corresponding author: Hamid Dezhampanah, Laboratory of Physical Chemistry, Department of Chemistry, Faculty of Science, University of Guilan, P.O. Box 41335-1914, Rasht 0098, Iran. Tel.: + 98 131 3243630 5; Fax: + 98 131 3233262; E-mail: h.dpanah@guilan.ac.ir
Abstract: In this study, we have investigated interaction of sertraline hydrochloride as antidepressant drug in pharmaceutical formulation with eosin Y dye in aqueous buffered medium by optical absorption and fluorescence spectroscopic measurement. Strong hypochromic–bathochromic effects in absorbance and quenching in fluorescence were observed that showed strong binding of eosin Y to this drug via ion pair formation. In order to explain the nature of eosin Y-drug interaction, the equilibrium constants and other thermodynamic functions for the process of eosin Y-sertraline ion pair formation were calculated using the UV-Visible absorption data. The results showed that formation of ion pair between eosin Y and sertraline was exothermic, characterized by large negative enthalpy and positive entropy changes.
Keywords: Eosin Y, sertraline hydrochloride, ion pair, equilibrium constant, fluorescence spectroscopy
