Novel method for the coating of positively charged liposomes with modified chitosan was elaborated. Liposomes were prepared by stepwise extrusion through inorganic membranes (Anotop) of 0.2 and 0.1 μm pore sizes. Chitosan derivatives were synthesized via the Ugi multicomponent reaction. Several series of liposomal compositions were produced and their properties were compared in terms of particle size, polydispersity index (PDI), zeta potential and stability. The effect of various additives was investigated and the optimal composition of the lipid film was determined. The addition of the uncharged fatty esters allowed the diameter of the liposomes obtained by extrusion to be reduced to 145-150 nm with a PDI of 0.13-0.15. The prepared liposomes were loaded with the novel antiviral drug Triazavirin and used to determine the release profile. Triazavirin was included into liposome layer as a salt with biocompatible choline derivatives of limiting fatty acids. The appropriate lipid composition was used for the preparation of a larger quantity of liposomes coated by modified chitosan. It was shown that an appropriate combination of liposomes and polysaccharide layer potentially extended colloidal stability by up to 3 months and exhibited broad functional capabilities for surface modification.

An arginine-rich peptide dendrimer, LTP, is a new low-toxicity promising tool for intracellular gene delivery.

Novel artificial peptides possess anti-RSV activity through a combination of two mechanisms: direct nonspecific destabilization of the viral envelope and competitive interaction with the RSV cellular receptor.

Anodic aluminum oxide (AAO) ceramic membranes with macroscopically aligned and hexagonally packed nanopore architecture are attractive substrates for forming nanotubular lipid bilayers as well as sorption and catalytic media because of a tunable pore diameter, robust pore structure, and low fabrication cost. Here we employed continuous wave X-band (9 GHz) EPR of two pH-sensitive nitroxide radicals to assess acid−base properties AAO membranes prepared from low-cost commercial grade aluminum and compared those with commercial Anodisc membranes from Whatman, Ltd. The AAO membranes with pore diameters ≥58 ± 8 nm showed essentially the same pH inside the pores, pH int , as the bulk external solution, pH ext , over the 0.1−3.0 M range of ionic strength. However, the apparent pK a of nitroxide probes inside the pores deviated from the bulk values for the nanopores of smaller diameters of ca. 29 and 18 nm. Specifically, for the latter nanopores the values of pH int were found to be 0.5−0.8 pH unit lower than the bulk pH ext . An increase in acidity of the bulk solution led to a steady decrease of the negative charge on inner surface of the 38 nm nanopores and its recharge from a negative to a positive value at pH 4.7 ± 0.1, corresponding to the point of zero charge (pzc). Overall, the EPR titration method described here could assist in characterization of meso-and nanoporous membranes for catalytic and sorption applications as well as act a support medium for self-assembled biomembrane systems.

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