Extruded vesicles of dioctadecyldimethylammonium bromide and chloride investigated by light scattering and cryogenic transmission electron microscopy
2008 (English)In: Journal of Colloid and Interface Science, ISSN 0021-9797, Vol. 322, no 2, 582-588 p.Article in journal (Refereed) Published
Combined dynamic and static light scattering (DLS, SLS) and cryogenic transmission electron microscopy (cryo-TEM) were used to investigate extruded cationic vesicles of dioctadecyldimethylammonium chloride and bromide (DODAX, X being Cl- or Br-). In salt-free dispersions the mean hydrodynamic diam., D h , and the wt. av. mol. wt., M w , are larger for DODAB than for DODAC vesicles, and both D h and M w increase with the diam. (f) of the extrusion filter. NaCl (NaBr) decreases (increases) the DODAB (DODAC) vesicle size, reflecting the general trend of DODAB to assemble as larger vesicles than DODAC. The polydispersity index is lower than 0.25, indicating the dispersions are rather polydisperse. Cryo-TEM micrographs show that the smaller vesicles are spherical while the larger ones are oblong or faceted, and the vesicle samples are fairly polydisperse in size and morphol. They also indicate that the vesicle size increases with f and DODAB assembles as larger vesicles than DODAC. Lens-shaped vesicles were obsd. in the extruded prepns. Both light scattering and cryo-TEM indicate that the vesicle size is larger or smaller than f when f is smaller or larger than the optimal f * ~ 200 nm .
Place, publisher, year, edition, pages
2008. Vol. 322, no 2, 582-588 p.
DODAB, DODAC, cationic vesicle, extruded vesicle, lens-shaped vesicle, light scattering, cryo-TEM
IdentifiersURN: urn:nbn:se:uu:diva-16370DOI: 10.1016/j.jcis.2008.03.015ISI: 000256161500027PubMedID: 18402974OAI: oai:DiVA.org:uu-16370DiVA: diva2:44141