Aggregation behavior of aqueous dioctadecyldimethylammonium bromide/monoolein mixtures: A multitechnique investigation on the influence of composition and temperature

Development of Dioctadecyldimethylammonium Bromide/Monoolein Liposomes for Gene Delivery

“…1) that reveals a tworegion phase diagram consisting of either DODAB or MO enriched zones [40]. If ΧDODAB 0.5, bilayer-based structures dominate (Fig.…”

“…If ΧDODAB 0.5, bilayer-based structures dominate (Fig. 1A', 1B') and their size and fluidity depend on the molar composition of the mixture, with DODAB gel phase appearing as hydrated crystals [40]. When ΧDODAB < 0.5, aggregates are dominated by densely packed cubicoriented particles, visible as a cubic isotropic phase (Q) associated with high MO contents ( Fig.…”

“…DODAB's main limitation is the relatively high gel-to-liquid crystalline phase transition temperature (TM = 45°C ) [ 5 3 -5 6 ] , s u p e r i o r t o t h e h u m a n physiological temperature (TM = 37°C), meaning that DODAB's bilayers display a strong rigidity at normal body temperature which greatly limits its use as a delivery agent. This limitation can be counteracted by including a co-lipid with a lower TM value, such as DOPE [57,58], cholesterol [59,60] or MO [40], which will lower the TM of the lipid mixture.…”

“…It possesses a single unsaturated acyl chain (C18:1) attached to a glycerol headgroup [63]. Its tendency to form inverted bicontinuous cubic phases has been explored in the past for different applications such as protein crystallization [64,65] or matrix for gel electrophoresis [66], and justifies the structural richness of the liposomal system formed with DODAB [40].…”

“…When ΧDODAB < 0.5, aggregates are dominated by densely packed cubicoriented particles, visible as a cubic isotropic phase (Q) associated with high MO contents ( Fig. 1D', 1E') [40].…”