ИСТИНА

Spherical lipid bilayer 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 liposomes, composed of anionic palmitoyloleoylphosphatidylserine (POPS) and zwitterionic dioleoylphophatidylcholine (DOPC), with bilayered vesicles composed of cationic poly(L-lysine)-b-poly(L-leucine) block copolypeptides for concentration of liposomes within a small volume. This approach allows one to create multiliposomal carriers filled with different substances at desirable content ratios. We demonstrate how to manipulate with number of liposomes that could be ultimately adsorbed on polypeptide vesicles and the stability of the complexes in water-salt media by varying of POPS fraction in the liposomal membrane. The complexes were found to have low cytotoxicity. Also polypeptide vesicles and their complexes with liposomes are effectively digested by proteolytic enzyme trypsin. The effectiveness of interaction of the complexes with cell membranes was shown by fluorescence microscopy. These findings as well as the high potential for loading of anionic liposomes and cationic vesicles with biologically active compounds make these multi-liposomal complexes promising in the drug delivery field. This work was supported by Russian Science Foundation (project 14-13-00255)