Giant Phospholipid Vesicles from Double Emulsions

Investigators: Insun Yoon, Anderson Shum and Daeyeon Lee

Vesicles made from phospholipids (also known as liposomes) provide excellent model systems for studying the biophysics of plasma membranes. Also these liposomes hold much promise in the areas of encapsulation and delivery of active ingredients. In this project, we aim to fabricate phospholipid vesicles from double emulsions (water-in-oil-in-water droplets) which are prepared by using a glass microcapillary device. Using our technique, it is possible to continuously generate monodisperse liposomes and at the same time achieve high encapsulation efficiency.

Figure showing the generation of W/O/W double emulsions using a glass capillary microfluidic device. Phospholipids are dissolved in the oil phase.

After evaporation of the oil phase which contains phospholipids, it is possible to create monodisperse liposomes. High encapsulation efficiency of our method was confirmed by adding fluorescently labeled microspheres.

Scheme showing the formation of phospholipids vesicle from double emulsion (W/O/W droplet)

Bight field (left) and fluorescence (right) microscope images of DPPC vesicles created from double emulsions. Texas red-labeled DHPE and fluorescently labeled microspheres (~ 1μm) were added to the oil and inner aqueous phase, respectively.

We are investigating the mechanism of vesicle formation and the effect of phase transition temperature on the stability of liposomes during liposome formation process. In addition, the structure and mechanical properties of the liposomes will be further investigated using confocal microscopy and micropipette aspiration.