Self-assembled structures in excess and salt-free catanionic surfactant solutions

The stable self-assembled structures and the properties in cationic and anionic (catanionic) surfactant solutions were reviewed and summarized. Two aspects of the recent results are focused on: one is the catanionic surfactant systems containing the excess salts in aqueous solutions formed from the combination of the two compounds, and another is the 'true', salt-free catanionic surfactant systems having the acidic (H+) and basic (OH-) as the counterions for the cationic and anionic surfactants, respectively, which form water by the combination of the counterions. Some particularly self-assembled aggregates such as discs of finite size, regular hollow icosahedra, and vesicles are introduced. These particular aggregates are expected to be of practical value for special material synthesis, controlled drug and DNA release, etc. (C) 2004 Elsevier Ltd. All rights reserved.