Interactions of Vitamin K 3 with Herring-Sperm DNA Using Spectroscopy and Electrochemistry

Abstract

By means of ultraviolet-visible (UV-Vis) and fluorescence spectra, the binding ratio between vitamin K₃ and herring-sperm DNA in a physiological pH environment (pH = 7.40) was determined as n_K3: n_DNA = 2:1, and the binding constants of vitamin K₃ binding to DNA at different temperatures were determined as Kθ_298K = 1.28 × 10⁵ L.mol⁻¹ and Kθ_310K = 7.19 × 10⁴ L.mol⁻¹, which were confirmed using the double reciprocal method are Δ_rH_mθ = −3.57 × 10⁴ J.mol⁻¹, Δ_rG_mθ = −2.92 × 10⁴ J.mol⁻¹, and Δ_rS_mθ = 217.67 J.mol⁻¹K⁻¹. The driving power of this process was enthalpy. An intercalation binding of the vitamin K₃ with DNA was supported by a competitive experiment using acridine orange (AO) as a spectral probe. By combination analysis of the Scatchard method and cyclic voltammetry, we suggested that the interaction mode between vitamin K₃ and herring-sperm DNA would be a mixed mode. The quinonoid, duality fused-ring of vitamin K3 can intercalate into the base pairs of DNA, and there is an electrostatic binding along with intercalation binding.