ABSTRACT
This chapter describes how to manipulate giant unilamellar vesicles (GUVs) with optical traps, and especially with a dual-beam laser trap—called an optical stretcher, to extract their mechanical and thermodynamic properties. After a brief general introduction to optical traps, the chapter presents the basic principles of the optical stretcher that enables the deformation of vesicles without any contact. The chapter explains how to use the optical stretcher with an appropriate laser source, either to deform and extract mechanical properties of GUVs, or to heat GUVs intentionally in order to perform some thermodynamic characterization. When several wavelengths are combined in one setup, it is also possible to manipulate vesicles optically and to control their temperature almost independently.
