Plasmids occur in bacteria, yeast, and certain more complex cell types.
The primary lipid chemical constituents of cell membranes are all chemically related to detergents. The population of 23 nanometer spherical particles is monodisperse and stable in physiological conditions over days, and with a negative surface potential. The authors suggest the properties of these particles should ensure good tissue dissemination and escape from the bloodstream after intravenous injection, and that the most promising future for these small negatively charged DNA- containing particles will be in vivo artificial gene delivery without the immunological problems raised by viruses.