Synthesis and Electro-Optical Properties of a Novel DNA-Lipid Complex Carrying Carbazole Moieties

摘要

A novel DNA-lipid complex carrying carbazole (Cz) moieties was prepared by substituting the sodium counter cation with cationic lipid, namely lipid(2Cz), in which the actual mole ratio of phosphate to lipid was 1:1.05. The DNA-lipid(2Cz) complex was soluble in common organic solvents including CHCl3, CH2Cl2, methanol, and ethanol, while insoluble in THF, toluene, and water. CD spectroscopy revealed that the DNA-lipid complex took a predominantly double helical structure in methanol and that the helical structure was fairly stable against heating. A solution of the DNA-lipid(2Cz) complex emitted fluorescence in 40.0% quantum yield, which was lower than that of the corresponding lipid(2Cz) (76%). The cyclic voltammograms of the complex indicated that the oxidation potential of DNA-lipid(2Cz) was 0.65 V. The onset temperature of weight loss of the DNA-lipid complex is 230 degrees C according to TGA in air.