Electrochemical Studies On The Interaction Between G-quadruplex DNA And Derivatives Of Perylene

Currently, G-quadruplex DNA structure and its unique physiological function provide a new opportunity for the development of anticancer drugs. The compounds which can induce or stable G-rich single DNA to form G-quadruplex, can inhibit telomerase activity or reduce the expression of cancer gene transcription, so as to achieve the purpose of anti-tumor. As its higher selectivity, these compounds can effectively reduce both the toxic effects of chemotherapeutic drugs and significantly inhibit the recurrence of cancer. So establishing a new method which can screen G-quadruplexes-targeting molecules fast, easily, cheaply and high-throughput, have a great significance. In this paper, several electrochemical methods were used to study the interactions between G-quadruplexes DNA and derivations of perylene, and binding constants were obtained. The main results are listed as follows:(1) A series of perylene derivatives have been synthesized, and characterized by infrared spectroscopy, nuclear magnetic resonance.At the same time, a detailed study on the fluorescence properties of PDI1 in different solvents was carried out. The results indicated that using dioxane or dioxolane and water as component solvent, the fluorescence intensity of PDI1 is 100 times higher than using only water as solvent. Fluorescence lifetimes about PDI1 in different solvents obtained by time-correlated single electron measurements.(2) The change of G-quadruplex DNA structure in K+ solvent was studied by electrochemical impedance spectroscopy (EIS). The results that different gradients appeared in electrochemical impedance diagrams with the increase of K+ concentration indicate that the G-quadruplex DNA structure has been changed.(3) Interaction between G-quadruplex DNA and derivatives of perylene in different PH conditions were studies by Cyclic voltammetry. The result show that the selectivity is different between double-stranded DNA and G-quadruplex DNA in different conditions, which is in agreement with reported results. So the electrochemical method is an effective technique to screen G-quadruplex-targeting molecules.