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© 2015 Macmillan Publishers Limited. Despite the recent progress in and demand for wet adhesives, practical underwater adhesion remains limited or non-existent for diverse applications. Translation of mussel-inspired wet adhesion typically entails catechol functionalization of polymers and/or polyelectrolytes, and solution processing of many complex components and steps that require optimization and stabilization. Here we reduced the complexity of a wet adhesive primer to synthetic low-molecular-weight catecholic zwitterionic surfactants that show very strong adhesion (∼50 mJm-2) and retain the ability to coacervate. This catecholic zwitterion adheres to diverse surfaces and self-assembles into a molecularly smooth, thin (

An electrostatic complexation of liposomes, composed of anionic palmitoyloleoyl phosphatidylserine (POPS1-) and zwitterionic dioleoylphophatidylcholine (DOPC), with bilayer vesicles composed of cationic poly(l-lysine)-b-poly(l-leucine) block copolypeptides has been investigated. The complexation was characterized by several physicochemical methods with the following main conclusions: (a) all added liposomes are totally adsorbed on the polypeptide vesicles up to a certain saturation concentration. (b) The calculated number of liposomes per a single polypeptide vesicle is about 60. (c) The liposomes remain intact (i.e., do not leak) after being complexed with the vesicles. (d) Complexes are stable in physiological ionic strength solution with [NaCl] = 0.15 M. (e) The vesicles are effectively digested by proteolytic enzyme trypsin even when covered by liposomes. 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.

Imaging of transition of vesicles to micelles was undertaken.

Issues concerning the examination of the core-corona structures of poly(ethyleneoxide)/polybutadiene block copolymer micelles by transmission electron microscopy at liquid nitrogen temperature are discussed.

A series of surfactants linked by a hydrocarbon spacer (CsH2s) are synthesized to study the effects of disturbing the arrangement of polar heads on the properties of surfactants in aqueous solution. The short spacers promoted micelle growth and lead to viscoelasticity in the said surfactants, CsH2s-alpha, omega -(C12H25N+(CH3)2Br-)2. The technique used could be useful in the regulation of ampiphile self-aggregation.

A study was conducted to examine the phase behavior and aggregation in mixed aqueous solutions of the anionic UV-absorber 2-phenylbenzimidazole-5-sulfonic acid sodium slat, PhBSA (Na salt), and the cationic surfactant cetyltrimethylammonium bromide, CTAB. The results showed that the aqueous mixtures of the stiff anionic compound PhBSA and the cationic surfactant CTAB have a rich and time-dependent phase behavior.

The thermal pattern on a heated wall was studied for the flow of water and drag-reducing surfactant solutions in a channel. The wall of the channel was made of the thin foil, which was heated by direct current.