Vesicle adhesion depicted at nanoscale with normalized total internal reflection fluorescence microscopy

Abstract

We propose a novel fluorescence microscopy technique to study the adhesion of Giant Unilamellar Vesicles. Their adhesion is assessed through the normalization of Total Internal Reflection Fluorescence (TIRF) images by epi-fluorescence ones. This can be achieved by using a motorized rotatable mirror to switch from epi-fluorescence to TIRF. This method allows us to study the vesicle adhesion from ultra-weak to strong membrane surface interactions and to measure the absolute distance between the vesicles and various chemically functionalized glass substrates at the nanoscale.