STED Fluorescence Nanoscopy

Abstract

The turn of the twenty-first century has witnessed the advent of far-field (lens-based) fluorescence nanoscopy, a fluorescence microscopy featuring a spatial resolution down to molecular scales. Lens-based optical microscopy is a very popular technique for investigating the living cell, but the spatial resolution of its standard versions is limited to about 200 nm due to diffraction, impeding the imaging of molecular assemblies at smaller scales. Being the first of such nanoscopy techniques, STED microscopy was for a long time considered as a very complex technique, hard to apply in everyday biological research. However, recent years have seen major improvements of the STED nanoscopy approach, and STED microscopes are becoming increasingly widespread, nowadays providing turnkey sub-diffraction resolution imaging in open imaging facilities. Based on recent publications, we give a brief overview of some of the improvements that made these developments possible, a short insight into successful applications, as well as a brief comparison to other far-field fluorescence nanoscopy techniques.