Zd. Xiao et al., Preparation of asymmetric bilayer-vesicles with inner and outer monolayerscomposed of different amphiphilic molecules, SUPRAMOL SC, 5(5-6), 1998, pp. 619-622
Asymmetric vesicles were prepared layer by layer from reverse micelles. The
aqueous solution was first entrapped into reverse micelles prepared from l
ipid, then these reverse micelles penetrated the monolayer formed by anothe
r kind of amphiphilic agent at organic solvent/water interface by centrifug
ation and were assembled spontaneously by the second layer to form asymmetr
ic vesicles. In general, the diameters of the vesicles ranged from 30 to 10
0 nm. A fluorescein quenching experiment showed that asymmetric vesicles wi
th the inner layer being lipid and the outer layer being single-chain amphi
philic molecules, [(bpy)(2) Ru(diazafluorenone) (CH2)(15)CH3](PF6)(2), were
successfully prepared. The half-life of flip-flop of the amphiphilic molec
ules between inner and outer layers was estimated to be about 17 days. (C)
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