Production of phospholipid giant vesicles for application as biomembrane mimetic systems

Abstract

Giant vesicles are basically formed by one or a few lipid bilayers, have dimensions varying from 10 to 50 micron and are suitable models for primary cells in terms of size, membrane composition and ability to encapsulate biological molecules. These research fields are widely investigated by Professor Carlos M. Marques, specialist in biomembrane mimetic systems at institute Charles Sadron, University of Strasbourg, France. Hence the motivation for the development of this project with Professor Marques`s research group, which would complement the studies of our group in relation to biomembrane mimetic systems. In this project the electroformation technique is applied in the fabrication of giant unilamellar vesicles (GUVs) of phospholipids. In analogy to natural cells, composed of several molecules such as phospholipids and cholesterol, GUVs are also fabricated from ternary mixture of phospholipids and cholesterol in various proportions. The GUVs are then applied as biomembrane mimetic system in an interaction study with xanthene derivatives and other analytes of Professor Marques interest. The size of GUVs allows their direct observation by optical microscopy bringing greater level of detail about possible interactions with the analytes. Therefore, confocal optical microscopy, phase contrast and fluorescence microscopy are then used as characterization tools. The idea is to add the analytes to the vesicle outside and analyze possible modifications in phospholipid membrane as a function of their interaction. This project is part of the Ph.D project (FAPESP 2010/17965-0) titled " Layer-by-Layer (LbL) and Langmuir-Blodgett (LB) films of phospholipids as mimetic systems aplied in the intecation and sensing of xanthenes derivatives" in development at UNESP of Presidente Prudente. (AU)