NOVEL PROPERTIES OF MOLECULAR ASSEMBLIES OF ISOPRENOID SURFACTANTS

Unlike micelles of straight hydrocarbon chain-surfactants, isoprenoid surfactants, CH3 [CH(CH3)CH2CH2CH2](3) CH(CH3)CH2 - R (R = CH2N+ (CH3)(3) Br-, CH2OPO3H- Na+, CH2OSO3- Na+, CO2- Na+), gave large globular and cellular assemblies in water which could be observed directly by transmission electron microscopy; critical micelle concentration of 0.3 similar to 1.4 x 10(-3) M at 20 degrees C, aggregation number of 2 similar to 15 x 10(4), and diameter of 200-2000 Angstrom. A basic structure of the assemblies was a thin layer with a thickness (about 30 Angstrom) which was close to the molecular length of the surfactants. The assemblies were decomposed during gel column chromatography; viz., they were not as stable as the liposomes of lecithins. The morphology was discussed in conjunction with a steric effect of the isoprenoid chain.