Organized assemblies in bolaamphiphile/oppositely charged conventional surfactant mixed systems.

Five ionic bolaamphiphiles were synthesized and the aggregation behavior of bola single systems and bola/oppositely charged conventional surfactant mixed systems was studied. Small spherical vesicles were formed in all these mixed systems revealed by transmission electron microscopy (TEM). Variation of the structure of the hydrophobic chain of bolaamphiphiles has great influences on the vesicle formation ability. Vesicles were also found in the single system of a carboxylate bolaamphiphile, which was attributed to the hydrolysis of the bolaamphiphile. The results of FT-IR and X-ray diffraction (XRD) showed that bolaamphiphiles spanned through the vesicle membranes in these mixed systems. Super thermostability of the vesicles in this kind of mixed system was also investigated.