A typical salt-free zero-charged catanionic system was constructed by mixing C14H29N+(CH3)(3)OH-(TTAOH) and lauric acid (LA). The electrochemical behaviors of K-4[Fe(CN)(6)] in salt-free TTAOH/LA micelle phase and vesicle phase solutions at glassy carbon (GC) electrode at different scan rate were obtained. A pair of well-defined redox peaks of [Fe(CN)(6)](3-/4-) is observed in TTAOH/LA vesicular solution with Delta E-p = 61 mV at the scan rate of 0.001 V/s. Compared to the electrochemistry of K-4[Fe(CN)(6)] in aqueous solution and TTAOH/LA micellar aqueous solution, the reversibility of [Fe(CN)(6)](3-/4-) is significantly improved in TTAOH/LA vesicular aqueous solution. (C) 2009 Elsevier B.V. All rights reserved.