Study on the interaction between the inclusion complex of hematoxylin with β-cyclodextrin and DNA

Ultraviolet-visible (UV-vis) spectra, fluorescence spectra, electrochemistry, and the thermodynamic method were used to discuss the interaction mode between the inclusion complex of hematoxylin with β-cyclodextrin and herring sperm DNA. On the condition of physiological pH, the result showed that hematoxylin and β-cyclodextrin formed an inclusion complex with binding ratio n(hematoxylin):n(β-cyclodextrin) = 1:1. The interaction mode between β-cyclodextrin-hematoxylin and DNA was a mixed binding, which contained intercalation and electrostatic mode. The binding ratio between β-cyclodextrin-hematoxylin and DNA was n(β-cyclodextrin -hematoxylin):n(DNA) = 2:1, binding constant was K(⊖)(298.15K) = 5.29 × 10⁴ L·mol⁻¹, and entropy worked as driven force in this action.