Nile red probing for the micelle-to-vesicle transition of AOT in aqueous solution

The micelle-to-vesicle transition of AOT in aqueous solution was well detected by fluorescence technique using Nile red (NR) as the probe. The results showed that the first turning points on Ia–C and Ia/Ib–C curves indicated the critical micelle concentration (cmc) of AOT, while the maximum in Ia/Ib–C curve well responded to vesicle formation. This is due to different locations of the probe in micelle and vesicle. In comparison with p-N,N-dimethylaminobenzonitrile (DMABN), the information about the molecular structure of the probe required to detect effectively the micelle-to-vesicle transition was obtained.