Spontaneous vesicle formation in aqueous solution of zwitterionic and anionic surfactant mixture

Vesicles form spontaneously in the aqueous mixtures of dodecyl sulfonate, b etaine (DSB) and sodium bis(2-ethylhexyl) sulfosuccinate (Aerosol OT (AOT)) at certain mixing ratios, which has been demonstrated by microcalorimeter, negative-staining transmission electronic microscopy (TEM) and quasi-elast ic light scattering (QELS) methods. The addition of NaCl will expand the ra nge of vesicle formation, and monodispersed vesicles are obtained in the so lution from the salinity of 0.03 to 0.09 M at the mixing molar ratio of 7/3 (DSB/AOT, mol/mol), with the polydispersity of the system lower than 0.1. To learn more about the structural change in the mixture, ultrasonic was em ployed finally. Meanwhile analysis was made from the viewpoint of molecular geometry structure. (C) 2001 Elsevier Science B.V. All rights reserved.