Size and stability of catanionic vesicles: Effects of formation path, sonication, and aging

• Type: Article in International Scientific Journal
• Date: 2000

Authors

Marques, EF (Author) FCUP

Journal

Title: Langmuir

Vol. 16

Pages: 4798-4807

ISSN: 0743-7463

Publisher: American Chemical Society

Indexing

ISI Web of Knowledge - 162 Citations

Scopus - 165 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-001-01X

DOI: 10.1021/la9908135

Abstract (EN): The majority of vesicles prepared from dispersions of phospholipids in water are nonequilibrium structures. Thermodynamically stable vesicles must display distinctive physicochemical properties. To investigate the size and stability properties of the vesicles formed in the catanionic mixture of single-tailed (SDS) and double-tailed (DDAD) surfactants, we evaluate the influence of the formation path on size, polydispersity, and equilibration time, by means of microscopy methods and water NMR self-diffusion. The different paths used involve mixing of solutions, mixing of solids, or dilution of preequilibrated concentrated samples. Water self-diffusion and microscopy show that all of the methods are able to yield vesicle solutions, but their size and polydispersity present some differences. Under the effect of a short sonication time, all solutions gain identical macroscopic appearance and with time they apparently equilibrate to a common state (as probed by water self-diffusion data). This stable state coincides with one of the previous formation paths - mixing of solutions.

Language: English

Type (Professor's evaluation): Scientific