Spontaneous Formation of Vesicles by Sodium 2-Dodecylnicotinate in Water

Abstract

The surface activity and aggregation behavior of a synthesized nicotinic acid based anionic surfactant, sodium 2-dodecylnicotinate, were studied in aqueous solution. The self-assembly formation was investigated by use of a number of techniques, including surface tension and conductivity measurements, fluorescence spectroscopy, dynamic light scattering measurement, gel permeation chromatography, and microscopy. The amphiphile exhibits two breaks in the surface tension vs concentration plot, indicating stepwise aggregate formation and thus producing two values of the aggregation concentration. Stepwise aggregation of the amphiphile was further confirmed by steady-state fluorescence spectroscopy using pyrene as a probe molecule, and also the micropolarity of the aggregates was determined. The rigidity of the microenvironment was estimated by determining steady-state fluorescence anisotropy using 1,6-diphenyl-1,3,5-hexatriene as a fluorescence probe molecule. The average hydrodynamic radius and size distribution of the aggregate suggest formation of larger aggregates in aqueous solution. The formation of vesicles in water was established by conductivity measurement and a dye entrapment experiment. The entrapment of a small solute and the release capability have also been examined to demonstrate these bilayers form enclosed vesicles. Transmission electron micrographs revealed the existence of closed vesicles and closed tubules in aqueous solution. Therefore, for the first time, it has been observed that this simple single-chain nicotinic acid based amphiphile spontaneously assembles to vesicles in aqueous solution.

Spontaneous Vesiculation and pH-Induced Disassembly of a Lysosomotropic Detergent: Impacts on Lysosomotropism and Lysosomal Delivery

“…At pH 4, and also at pH 7 with Triton X-100 added, the diffusion time of the slow component was reduced substantially, indicating disruption of the MSDH vesicles ( Figure 5B and Table 1). 31 , but also gemini surfactants 32,33,34 , catanionic 35,36 or other binary amphiphile systems 37, 38 39 , and indeed also some single-tailed amphiphiles 40,41,42,43,44,45 volume, into which molecules can be entrapped.…”

Vesicle formation of single-tailed amphiphilic alkyltrimethylammonium bromides in water induced by dehydration–rehydration

“…The inner aqueous cores of vesicles can entrap salt ions (K + and Cl À ions) and consequently prevent the entrapped charge carrier ions from contributing to the conductivity of the solutions. [36][37][38][39] In addition, the fluorescence technique was also used to confirm the existence of inner aqueous cores of the large aggregates observed above. The steady-state fluorescence spectra of the hydrophilic dye calcein in the vesicle-solutions of C n TABs (20-50 mM) were determined and compared with those in their micellesolutions (20-50 mM).…”

Effect of amide hydrogen bonding on spontaneously formed gel-emulsions by two pyridyl carboxylic acid based amphiphiles, sodium salt of 2-dodecylpyridine-5-carboxylic acid and sodium salt of [2-dodecylpyridine-5-carboxylic]glycine: entrapment and release of vitamin B12

“…55 DDPC was synthesized and puried according to the procedure described elsewhere. 42 The molecular structure of the compound was determined by 1 H NMR and LC-mass spectra. The details of the chemical identication of the molecule are included in the ESI [Fig.…”

“…41 Our group has recently reported the synthesis and interesting self-assembly properties of a nicotinic acid based surfactant, sodium 2-dodecylnicotinate. 42 In this context, we have attempted to demonstrate the gelation behavior of two amphiphiles, the sodium salt of 2-dodecylpyridine-5-carboxylic acid (SDDPC) and the sodium salt of [2-dodecylpyridine-5carboxylic]glycine (SDDPCG) [Fig. 1].…”