Fig. 3: Dronpa-2 for characterization of illumination in confocal microscopy equipped with a pulsed laser in the raster scanning mode.
a–f, Dronpa-2-labeled nucleus of a fixed U-2 OS cell. a, Initial image. b, Time evolution of the averaged fluorescence over the whole nucleus (circles, experimental data; solid line, monoexponential fit, τ = 1.9 µs). The corresponding evolution from a central portion of the overall image of a 10 μM Dronpa-2 solution sandwiched between two glass slides is shown with triangles (τ = 2.1 µs). c–f, Maps (c,e) and histograms (d,f) of the characteristic time τ (c,d) and light intensity (e,f) (Supplementary Table 3). g,h, Setup (g) and map of light intensity retrieved from Dronpa-2-labeled E. coli bacteria imaged at the surface or through a 2% agarose pad by changing the sample orientation (h). Solvent was Tris buffer pH 7.4 (50 mM Tris, 150 mM NaCl); T = 293 K. λexc = 488 nm; 500 nm < λem < 550 nm. Scale bar, 12 μm (a,c,e) (text and Supplementary Tables 1–3). Independent repeats, 4 (a,c,e); 3 (h).
