Electrostatic complexes of liquid and solid liposomes with spherical polycationic brushes

The complexation of anionic liposomes and polymeric microspheres with grafted polycationic chains (spherical polycationic brushes) is studied. Three types of liposomes with the same molar amount of the anionic lipid are used, namely, liquid liposomes with a high mobility of lipids within the bilayer, solid liposomes with limited lateral and transmembrane mobility of lipid molecules, and solid liposomes with embedded cholesterol. All liposomes efficiently adsorb on the surface of brushes. Upon adsorption, solid liposomes begin to “leak,” that is, to release water-soluble contents in the surrounding solution, whereas solid liposomes with the embedded cholesterol preserve their integrity. Cholesterol-containing liposomes are of interest for obtaining multiliposomal containers with encapsulated biologically active compounds, catalysts, diagnostic agents, etc.