Investigation of the Interaction of Sertraline with Calf Thymus DNA by Spectroscopic Methods

The interaction of the antidepressant drug, sertraline, with calf thymus double stranded DNA (dsDNA) in physiological buffer (pH 7.4) was investigated by UV-Vis spectrophotometry, spectrofluorimetry, circular dichroism, Fourier transform infrared spectroscopy (FTIR), viscosity measurements and DNA melting studies. The absorption spectra of the drug with DNA showed a hyperchromic effect. Using Hoechst reagent as a fluorescence probe, quenching of the emission peak occurred in the DNA-Hoechst mixture when sertraline was added. The FTIR spectra revealed minor groove binding mode between the drug and the dsDNA. The binding constant of sertraline to DNA was calculated using spectroscopic data. The calculated thermodynamic parameters suggested that electrostatic interactions are important forces in the formation of sertraline-DNA complex.