title: Imaging of membrane proteins using antenna-based optical microscopy.
abstract: The localization and identification of individual proteins is of key importance for the understanding of biological processes on the molecular scale. Here, we demonstrate near-field fluorescence imaging of single proteins in their native cell membrane. Incident laser radiation is localized and enhanced with an optical antenna in the form of a spherical gold particle attached to a pointed dielectric tip. Individual proteins can be identified with a diffraction-unlimited spatial resolution of ∼50 nm. Besides determining the concentration and distribution of specific membrane proteins, this approach makes it possible to study the colocalization of different membrane proteins. Moreover, it enables a simultaneous recording of the membrane topology. Protein distributions can be correlated with the local membrane topology, thereby providing important information on the chemical and structural organization of cellular membranes.
authors.affiliation: The Institute of Optics and Department of Biomedical Engineering, University of Rochester, Rochester, NY 14627, USA.
authors.forename: Christiane
authors.initials: C
authors.lastname: Höppener
authors.forename: Lukas
authors.initials: L
authors.lastname: Novotny