Novel dicationic pyrimidinic surfactant: Self-assembly and DNA complexation

Abstract

Novel pyrimidinic surfactant with two morpholinium head groups and two decyl tails has been synthesized. As determined by breakpoints on concentration dependences of surface tension and conductivity, the pyrimidinic amphiphile forms aggregates beyond critical micelle concentration of 3.4 mM, which is supported by fluorescence ratiometry, dye solubilization technique and dynamic light scattering data (DLS). The NMR self-diffusion data testify that different types of aggregates are probably formed in the solution above 12 mM. The dual structural behavior is in line with fluorescence anisotropy results and packing parameter calculations. The complexation ability of the pyrimidinic amphiphile toward plasmid DNA pK18 is supported by DLS and zeta potential measurements indicating the occurrence of the compaction and charge neutralization effect. The lipoplex formation is also supported by ethidium bromide exclusion data. The ability of the amphiphile of integrating with lipid bilayer is revealed by measurements of the temperature of main phase transition.