Zn²⁺-induced vesicle formation

Zn²⁺-induced vesicle formation has been studied for the first time in aqueous mixtures of tetradecyldimethylamine oxide (C₁₄DMAO) and zinc 2,2-dihydroperfluorooctanoate [Zn(C₆F₁₃CH₂COO)₂]. The charged vesicle phase without any cosurfactants was prepared in the aqueous mixtures. The charged vesicle phase has interesting rheological properties. This ionically charged vesicle phase is not shielded by excess salts because of salt-free aqueous solutions. Such a vesicle phase is important for many applications where cosurfactant is not used. A cationic/anionic surfactant C₁₄DMAOH^{+ -}OOCCH₂C₆F₁₃ system could be produced from C₁₄DMAO/Zn(C₆F₁₃CH₂COO)₂ mixtures because the zwiterionic surfactant C₁₄DMAO can be charged by the H⁺ released from H₂S to a cationic surfactant and Zn²⁺ is precipitated. After ZnS particles are removed from the cationic/anionic surfactant solutions, the finally mixed sample does not contain excess salts as do other studied cationic/anionic surfactant systems. The sample is a birefringent Lα-phase and consists of unilamellar and multilamellar vesicles. The novel vesicle reproduction route should provide a new method to prepare nanoscale particles.