Differential scanning microcalorimetric study of vesicles in aqueous solutions formed by dimethyldioctadecylammonium bromide

Abstract

Differential scanning microcalorimetric data for dimethyldioctadecylammonium bromide (DOAB) in dilute aqueous solutions prepared using different protocols including an ethanol injection method are compared. Reproducible data are obtained for solutions prepared using a hot-water method. Scans for very dilute solutions show evidence for processes controlled by both inter- and intra-vesicular interactions. An extremum in the scans near 47 °C is assigned to a gel to liquid crystal transition involving local domains within each vesicle comprising ca. 130 DOAB monomers.