Abstract
Novel monomethine cyanine dye (MC) derived from beta-naphthothiazole and benzothiazole has been prepared and characterized by H-1 and C-13 NMR, FTIR, ESIMS, elemental analyses, absorption and fluorescence spectroscopy. The dye was conveniently synthesized by the condensation of two sulfate heterocyclic quaternary salts. The interaction between calf thymus DNA (ct-DNA) in tris(hydroxymethyl)aminomethane-HCl (Tris-HCl) aqueous buffer solution and MC has been studied with spectral fluorescence method. The binding constant value has been determined by fluorescence titration of MC with ct-DNA concentrations. The result obtained is consistent with an intercalative binding interaction between MC and ct-DNA. Compared with ethidium bromide (EB). MC showed a huge fluorescence enhancement upon mixing with ct-DNA. (C) 2010 Elsevier B.V. All rights reserved.