Spontaneous Vesicle Formation from Aqueous Solutions of Didodecyldimethylammonium Bromide and Sodium Dodecyl sulfate Mixtures

Wirkstofftransport mit weicher Materie: Matrix‐ und Vesikelvektoren

“…Dies ist eine der besten Verkapselungseffizienzen, die bisher für katanionische Vesikeln mit äquimolaren Tensidanteilen erzielt wurden. [118,119,127] …”

Phase Behavior of Mixed Solutions of a Cationic Surfactant with a Ferrocenyl Group and an Anionic Surfactant: Surface Chemical and Electrochemical Approaches

“…CPP = v/a 0 l c (4) where v is the volume of the hydrophobic group of surfactant molecule, a 0 the area occupied by the hydrophilic group at an interface of the aggregate, and l c the length of the hydrophobic group. Surfactant molecules form spherical micelles, cylindrical micelles, vesicles, and planar bimolecular membranes when the value of CPP is below 1/3, lies between 1/3 and 1/2, ranges from 1/2 to 1, and approaches to 1, respectively (12). The values of CPP for the surfactants used in the present study (FTMA + and SDBS) would be both smaller than 1/2 since their molecules form spherical or cylindrical micelles (26) in dilute solutions.…”

“…The first type is for those systems in which single surfactant forms a lamellar phase (planar bimolecular membrane) which forms vesicles on addition of another component and reported by Evans et al (6)(7)(8)(9)(10), Kaler et al (11), and Abe et al (12,13). The second type covers mixed solutions of two single-chain-type surfactants, each of which forms spherical micelles in water, and described by Gebicki and Hicks (14,15), Hargreaves et al (16), Jain et al (17), Kaler et al (18), and Abe et al (19).…”

Phase Behavior and Spontaneous Vesicle Formation in Aqueous Solutions of Anionic Ammonium Dodecyl Sulfate and Cationic Octadecyl Trimethyl Ammonium Chloride Surfactants

“…6 Recently, vesicles have also provided compartments for preparation of nanoparticles. [7][8][9] There have been observations of spontaneously formed vesicles in mixtures of surfactants; to name a few of them, for catanionic systems with single alkyl chains cetyltrimethylammonium tosylate (CTAT)/sodium dodecylbenzene sulfonate (SDBS), 5,10,11 dodecyltrimethylammonium chloride (DTAB)/sodium dodecyl sulfate (SDS), 12,13 cetyltrimethylammonium bromide (CTAB)/sodium petyl sulfate (SPS), 14 CTAB/SOS (sodium octyl sulfate), 14,15 and CTAB/SPDS (sodium pentadecyl sulfate) 14 and for mixtures of cationic surfactant with double alkyl chain and anionic surfactant with single alkyl chain didodecyldimethylammonium bromide (DDAB)/SDS 16 and DDAB/sodium decyl sulfate (SDeS) 17 have been examined. Cationics have been known to exhibit excellent antistatic effects and softness.…”

“…This finding is consistent with the previous observations that the greatest amount of precipitation was observed at an equimolar mixture. 17,45 The complexes (OTA-DS), which are highly insoluble in water, might consist of octadecyltrimethyl cation (OTA+) and dodecyl sulfate anion (DS-). During the formation of the precipitates, NH 4 Cl was produced and affected the pH of the mixture along with the unreacted monomer ions and counterions.…”