Three hypotheses were considered to interpret this result. One hypothesis is that the Fc12-Br exits the bilayer and dissolves in the aqueous regions as micellar aggerates. Another possibility is that the Fc12-Br induces a localized phase transition away from the Pn3m structure; the interfacial curvature of lipid membranes could be flattened leading to a 3D-2D phase transition of Pn3mlamellar (L ! ), which subsequently reduces the diffusivity of Fc12-Br. Finally, another option is that other processes occur, such as adsorption with the electrode surface leading to a passivating layers. To discriminate between these mechanisms, real-time SANS data were collected during electrochemical cycling, with and without contrast-matching of the majority lipid component. The scattering data would inform on the localisation of the electroactive surfactant, thus revealing any underlying mechanisms associated with the degradation in performance. The SANS pattern of 10% (w/w) Fc12-Br/d-MO(w/w) in H2O PB is shown in Figure . Both d-MO with and without 10% (w/w) Fc12-Br adopted Pn3m symmetry. However, the peak positions of 10% (w/w) Fc12/d-MO were shifted towards the low-q region, with q values of 0.082 and 0.099 Å -1 . The lattice cell dimension was estimated to be 110.3 Å. This implies that the lattice cell dimension of the mesophase is increased upon incorporating 10% (w/w) Fc12-Br. The swelling effect might be due to the electrostatic repulsions between the Fc12-Br molecules that inserted at the lipid/aqueous interface, which caused the curvature of the lipid membrane to flatten. The lattice parameter of 10% (w/w) Fc12-Br/d-MO obtained from SANS measurements is slightly greater than our previously acquired SAXS data, 99.3 Å. This result could be due to the uncertainties in preparing samples at microliter scales. The SANS pattern of SLDd-MO contrast matched 10%Fc12/d-MO in D2O PB is displayed in Figure . Notably, two peaks at q~ 0.082 and 0.099 Å -1 persisted after contrast matching (see Figure ). These peaks correspond to the incorporated Fc12-Br molecules, suggesting that the additives within the mesophase adopted the same symmetry as the d-MO host medium. A similar additive effect upon incorporation of membrane proteins into cubic phases has been reported. By combining these results, it can be concluded that the Nonetheless, the color of the Pt working electrode became darker after the electrochemical tests, suggesting that an interaction had occurred between Br -ions in the water channels and the metal electrode. The electrodeposition of Br -onto noble metal surface, for example Au and Pt, has been reported elsewhere. The resultant monolayer might act as an insulation layer that inhibits the Fc12 + from further interaction with the Pt working electrode, and thus leading to a reduction in the current peaks after each CV cycles. Since Br -ions may be the cause of this phenomenon, salt metathesis for Fc12-Br to replace the counter anion by [PF6] -was considered. The additive effect of varying the wt% Fc12-PF6 on the dimensionality of a MO cubic phase was investigated using SAXS. As shown in Figure , as the wt% Fc12-PF6 increases, the Bragg peaks of the material shift towards high-q region, suggesting that a shrinkage of the lattice cell parameter of the cubic phase. The MO cubic phase with Pn3m symmetry demonstrates the Fc12-PF6 uptake limit of 15% (wt%); at 20% Fc12-PF6, a mixed phase consists of Pn3m cubic phase and inversed hexagonal phase (HII) was formed.