Liposomes are artificially constructed vesicles consisting of a phospholipid bilayer. Due to their size and hydrophobic and hydrophilic character (besides biocompatibility), liposomes are promising systems for drug delivery. Liposome properties differ considerably with lipid composition, surface charge, size, and the method of preparation. We use microfluidic technology to generate monodisperse liposomes. With a combination of co-flow and flow-focusing, we generated double emulsion drops (a drop inside another drop) where the inner liquid is the liquid we want to encapsulate, the middle phase is a solution of lipids and the outer is an aqueous solution where our liposome will be dispersed. The advantage of this method is its high encapsulating efficiency and the control of the size of the liposome. Using this method, we produced liposomes with controlled sizes in the range 50-200 mm. We chose 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) to created our liposomes for its long tail (18 carbons). With all these variables fixed, we can focus on the effect of the surface charge. Changing the aqueous solution for a buffer comprising of chloride and iodide salts along with sodium and potassium salts will allow us to explore the effects of the Debye screening and ionic density on the liposomal size
