Fig. 5. Stimulated emission depletion (STED) nanoscopy. Representative data showing section planes of full-volume cells deconvoluted diffraction-limited (d-LCSM, green) and 3D super-resolution images (Red, d-3D STED). Zoomed in areas of the white square are shown in adjacent images, as well as the orthogonal representation of every axis (XY, XZ and YZ), where the increased resolution and better localization of 4⁴⁺ is shown in red. This reveals accumulation at specific locations within the cell membrane. Conditions: after 60 minute treatment with 4 μM 4⁴⁺, cells were washed with PBS before fixing with paraformaldehyde (4%).