DNA-binding study of anthraquinone derivatives using chemometrics methods

This work presents the interaction of two anthraquinones including quinizarin (1, 4-dihydroxyanthraquinone) and danthron (1, 8-dihydroxyanthraquinone) with CT-DNA in a mixture of Brittone-Robinson buffer (pH=7) with 50% of ethanol by UV-vis absorption, circular dichroism spectroscopic methods and viscosity measurements. The PCA and INDICES methods were used for predicting the number of light-absorbing components. Partially intercalative and hydrogen binding were found to be the dominant binding modes between anthraquinones and CT-DNA. The effect of ionic strength and pH on the behavior of the above system and also the interaction of anthraquinones with ds and ss-DNA were used to confirm the mentioned binding modes. The EQUISPEC software and nonlinear least-squares analysis were applied for binding constant determination.