Preparation and Characterization of DNA-Lipoglutamate Complexes

We newly prepared DNA–lipoglutamate polyion complexes by mixing aqueous solutions of DNA and cationic lipoglutamates such as α,γ-dibutyl glutamate (2C4N+), α,γ-dihexyl glutamate (2C6N+), and α,γ-dioctyl glutamate (2C8N+). Formation of the DNA–lipoglutamate complex was confirmed by gel chromatography, elemental analysis, CD spectra, and light scattering measurement. Compaction of DNA by binding with the cationic lipoglutamate was revealed by multi-angle light scattering. The DNA–lipoglutamate complexes showed the high stability for enzymatic hydrolysis by DNase I, which was confirmed by a quartz-crystal microbalance (QCM) technique. The DNA–lipoglutamate complexes showed the strong interactions with the lipid membranes and tumor cells compared with native DNA.