ИСТИНА

Liposomes represent an important category of nano-sized systems for biomedical applications. Due to unique structure, liposomes are used for encapsulation of different substances for improving their physical, chemical and operational characteristics. Hydrophobic molecules can be incorporated into the liposomal membrane, hydrophilic – into the inner water cavity. These features make liposomal containers promising for encapsulation and delivery of various therapeutic, diagnostic and cosmetic agents. Despite considerable progress in formation of liposomal containers, only a small amount of drugs based on liposomes has been applied. That is connected with such disadvantages of liposomes as its low thermodynamic stability, small volume of the container, absence of vector properties. We suggest electrostatic assembly of liposomes, composed of anionic palmitoyloleoyl phosphatidylserine (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. The physico-chemical properties and biodegradation of such complexes were investigated. It was shown that: 1) polypeptide vesicles effectively adsorb anionic liposomes on its surface; 2) these complexes are stable in water-salt media; 3) the liposomal structure remains intact after complexation; 4) both polypeptide vesicles and its complexes with anionic liposomes are are effectively digested by proteolytic enzyme trypsin. The effectiveness of interaction of the complexes with cell membranes was shown by fluorescence microscopy. Acknowledgements. The financial support of the Russian Science Foundation (project 14-13-00255) is acknowledged.