Preparation and characterization of non-equilibrium giant unilamellar vesicles

Abstract

Vesicles are spherical-shaped structures formed by the self-assembly of lipids bilayers. Several types of vesicles have been described during the past years due to its potential scientific interest. Specifically, giant unilamellar vesicles or GUVs, have been deeply studied because of its similarity with cell membranes and also they have been used as a model system to study a broad number of features. Thanks to their big size and volume in comparison with other type of vesicles, GUVs attract the interest of many scientific fields such as soft matter physics, chemistry and biotechnology1. This last one is probably the most relevant as, in medical fields, GUVs are proposed to be drug vehicles and an important part inside drug-delivering mechanisms. GUVs can encapsule active molecules and carry them to the site of interest but their fragility and short live are clear downsides that are being investigated. To be as accurate as possible and build a system close to real cell membranes, more than one lipid is further used to form GUVS. This aspect is extremely interesting because of the behavior of this lipids when they are altogether and when temperature changes. A segregation of two phases, also known as lipid raft, is expected and can be distinguished using fluorescence microscopy. Hence, in this project the main goal is the pursuit of a robust protocol to form big and stable GUVs and to observe how lipids dispose in different conditions