Effect of sonication and freezing–thawing on the aggregate size and dynamic surface tension of aqueous DPPC dispersions

Colloidal dispersion stability of unilamellar DPPC vesicles in aqueous electrolyte solutions and comparisons to predictions of the DLVO theory

“…(7). technique, provided evidence that mostly vesicles are present in such dispersions [9,10]. The images here show that the diameters of the vesicles ranged from 20 to 100 nm when observed 12 h after the dispersions were prepared, or from 30 to 200 nm 50 days later.…”

“…TEM showed that the vesicles had flat polyhedral-type edges in the proximity of other vesicles, when the distance between the vesicles seems to be about 2-5 nm. Even for individual vesicles cryo-TEM showed flat edges which are expected for solid-like (gel phase) particles [9]. Although the vesicles remained in a colloidally stable dispersion for hours or days, their average size increased with time (Fig.…”

“…This preparation protocol method was originally described in Refs. [6][7][8][9][10] and is designed to produce dispersions containing primarily fluid vesicles (unilamellar particles). The effect of sonication time was also examined.…”

“…With water DPPC forms fluid multi-lamellar liposomes or unilamellar vesicles above T c = 41°C, the chain melting transition temperature [2][3][4][5]. DPPC vesicular dispersions in water form only after extensive sonication above 41°C [6][7][8][9][10]. When these dispersions are cooled to 25 or 37°C, the vesicles become ''frozen", and the chains are in a solid-like state.…”

Fabrication and Characterization of Magnetoplasmonic Liposome Carriers

“…In previous reports, it has been shown that sonication can break down the large liposomes. Sonication can also produce unilamellar liposomes [33]. Therefore, our hypothesis is that stabilization of gold nanoshells through PVP coating and application of sonication during the fabrication procedure resulted in the formation of unilamellar liposomes with a high gold nanoshell encapsulation efficiency.…”