Dioctadecyldimethylammonium surfactant vesicles

An extraordinary way of stabilizing RUO2-coated CdS colloids for H2 generation was chosen by Fendler and co-workers The colloidal particles were generated in situ in surfactant vesicles of dioctadecyldimethylammonium chloride and dihexa-decyl phosphate. Thiophenol as a membrane permeable electron donor acted as a sacrificial additive. Later, a surface active re-usable electron donor (n-C,gH3,)2N — (CHj)—CH2—CHj—SH, Br was incorporated into the vesicles. Its R—SS—R oxidation product could be chemically reduced by NaBH to regenerate the active electron donor. The H2 yields in these systems were only 0.5 %. However, yields up to 10% were later reported for a system in which CdS was incorporated into a polymerizable styrene moiety, (n-C,jH3jC02(CH2)2) N (CH3) (CH2CgH4CH=CH2>, CP, and benzyl alcohol was used as the electron donor. 

NaA0T-n-heptane-H20 reversed micelles Single-compartment, 800-to 1000-A-diameter dihexadecylphosphate (DHP) surfactant vesicles Single-compartment dioctadecyldimethylammonium chloride (DODAC) (6) vesicles Thiophenolate-ion-capped, size-quantized CdS generated in situ in reversed micelles CdS particles prepared in situ in vesicles from Cd2+ by controlled exposure to h2s CdS particles generated in situ in DODAC vesicles by several methods... 

J. H. Fendler, W. L. Hinze, Reactivity control in micelles and surfactant vesicles - kinetics and mechanism of base-catalyzed-hydrolysis of 5,5 -dithiobis(2-nitrobenzoic acid) in water, hexadecyltrimethylammonium bromide micelles, and dioctadecyldimethylammonium chloride surfactant vesicles, J. Am. Chem. Soc, 1981, 103, 5439-5447. 

Surfactants have recently been used as models for membranes. Didodecyl-dimethylammonium bromide aggregates extensively in aqueous solutions into stable bilayer structures which further form vesicles and lamellae. Single compartment bilayer dioctadecyldimethylammonium chloride vesicles entrap and retain a number of substrates. Similar aggregation occurs with anionic amphiphiles with two normal alkyl groups as the hydrophobic residue. The hydrolysis of esters catalysed by a hydrophobic imidazole derivative occurs faster (up to 20-fold) in the intravesicle compared with the intervesicle reaction with didodecyldimethylammonium bromide. ... 

H.J. Watzke, J.H. Fendler, Quantum size effects of in situ generated colloidal cadmium sulfide particles in dioctadecyldimethylammonium chloride surfactant vesicles, J. Phys. Chem. 91 (1987) 854. 

Single-bilayer dioctadecyldimethylammonium chloride (DODAC) (6) vesicles Sonication of surfactant-stabilized magnetite with DODAC Vesicle-incorporated magnetite influenced the outcome of benzophenone photolysis 789... 

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