ИСТИНА

Spherical lipid bilayer vesicles (liposomes) are widely used for delivery of biological active substances. Hydrophilic compounds can be encapsulated into the inner water cavity of liposomes while the hydrophobic can be embedded into the liposomal membrane. We suggest electrostatic assembly of anionic liposomes with the use of polycationic colloid particles for concentration of liposomes within a small volume. This approach allows one to create multiliposomal carriers filled with different substances at desirable content ratios. Small unilamellar liposomes, prepared from mixtures of anionic and zwitterionic lipids, were complexed with polylactide micelles composed of mixture of amino-terminated lactide and co-polymer of lactide and polyethyleneglycol (PLAMs). To control the complexation and properties of the resulting complexes, the multi-method approach was used including fluorescence spectroscopy, dynamic light scattering, laser microelectrophoresis, cryogenic transmission electron microscopy, differential scanning calorimetry, conductometry, etc..The fraction of anionic lipid (α) in liposomes was found to be the critical factor that affects the aggregation stability of liposome/polyelectrolyte complexes, the reversibility of complexation and the integrity of polymer-bound liposomes. The use of PLAMsas carriers for the liposomes allowed us to obtain completely biodegradable multiliposomal compositions with low cyto-toxicity. The effectiveness towards breast carcinoma cells of the liposomal Cisplatin (antitumor drug) and liposomal drug form assembled on cationic carrier was demonstrated.