Synthesis and DNA interaction of a Sm(III) complex of a Schiff base derived from vanillin and L-tryptophan

  • Xing-ming Wang Department of Chemistry, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China
  • Yan Zhang Department of Chemistry, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China
  • Ting-ting Zhao Department of Chemistry, School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010, China
  • Li-sheng Ding Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China
Keywords: Vanillin, L-Tryptophan, Sm(III) complex of Schiff base, Herring sperm DNA, Interaction

Abstract

The interaction between the Sm(III) complex of an ionic Schiff base [HL]-, derived from vanillin and L-tryptophan, and herring sperm DNA at physiological pH (7.40) has been studied by UV-Vis absorption, fluorescence and viscosity methods. The binding ratios nSm(III) : nK[HL] = 1:1 and nSm(III)L: nDNA =5:1 were confirmed by a mole ratio method. The calculated binding constants of [Sm(III)L]+with DNA at 25 and 37oC were 1.19 × 105 M-1and 3.96 × 104 M-1, respectively. The thermodynamic parameters demonstrate that the interaction between [Sm(III)L]+ and DNA is driven mainly by enthalpy. Fluorimetric studies show that [Sm(III)L]+ is able to displace intercalated acridine orange. Combined with Scatchard methods, circular dichroism spectroscopy and viscosity measurements, the results indicate that the interaction between [Sm(III)L]+ and herring sperm DNA is mainly by intercalation with some groove binding.

KEY WORDS: Vanillin, L-Tryptophan, Sm(III) complex of Schiff base, Herring sperm DNA, Interaction

 

Bull. Chem. Soc. Ethiop. 2011, 25(2), 197-207.

Section
Articles

Journal Identifiers


eISSN: 1726-801X
print ISSN: 1011-3924