Interaction Mode between Inclusion Complex of Vitamin K₃ with γ- Cyclodextrin and Herring-Sperm DNA

ABSTRACT

Methods including spectroscopy, electronic chemistry and thermodynamics were used to study the inclusion effect between γ-cyclodextrin (CD) and vitamin K₃(K₃), as well as the interaction mode between herring-sperm DNA (hsDNA) and γ-CD-K₃ inclusion complex. The results from ultraviolet spectroscopic method indicated that VK₃ and γ-CD formed 1:1 inclusion complex, with the inclusion constant K_f = 1.02 × 10⁴ L/mol, which is based on Benesi–Hildebrand's viewpoint. The outcomes from the probe method and Scatchard methods suggested that the interaction mode between γ-CD-K₃ and DNA was a mixture mode, which included intercalation and electrostatic binding effects. The binding constants were K ^θ_25°C = 2.16 × 10⁴ L/mol, and K^θ_37°C = 1.06 × 10⁴ L/mol. The thermodynamic functions of the interaction between γ-CD-K₃ and DNA were Δ_rH_m^θ = −2.74 × 10⁴ J/mol, Δ_rS_m^θ = 174.74 J·mol⁻¹K⁻¹, therefore, both Δ_rH_m^θ (enthalpy) and Δ_rS_m^θ (entropy) worked as driven forces in this action.

KEYWORDS:

• Vitamin K₃
• γ-cyclodextrin
• herring-sperm DNA
• molecular probe

Acknowledgments

We are grateful for the apparatus support of the Analytical and Testing Center of Sichuan Normal University. This work was supported by National Natural Science Foundation of China (NO. 30973634) and Key Fund Project of Sichuan Provincial Department of Education (NO. 14ZA0027).