Figure 5.

STED nanoscopy with exchanging probes. (a) Fluorophores that dynamically bind and unbind from their target structure ensure a constant exchange and allow long-term STED imaging. (b) Repeatedly acquired STED nanoscopy images using regular and reversibly binding labels targeting the E. coli membrane or nucleoid. Cells were labeled with immobile (left images) or exchanging probes (right images). A high concentration of the exchangeable dyes JF₆₄₆-Hoechst and Nile Red was applied for the dynamic labeling of DNA (red) and E. coli membranes (green), respectively. Graphs on the right show intensity time trace of regular STED image, using exchanging probes at high and low STED laser intensities. Reprinted (adapted) with permission from [97].