Fig. 4: Four-colour STED imaging based on electrochemical fluorescence modulation.
From: Electrochemical fluorescence modulation enables simultaneous multicolour imaging
a, A U-2 OS cell was co-immunostained with STAR RED-tubulin, ATTO 655-phalloidin, SiR-DNA and STAR 635-paxillin. The raw image was generated by summing a total of six image frames. b, EC spectra of four dyes were measured at the respective labelled potential values; the STED images were captured at a frame rate of approximately 27 s. c, Electrochemical unmixed images of U-2 OS cells showing the structures for actin filaments, nucleus, paxillin and microtubules. d, The merged unmixed image was colour coded, with yellow representing the microtubules, magenta representing paxillin, red representing the nucleus and blue representing actin. e, Box plot (n = 6) showing the cross-talk factor for unmixed images. The boxes extend from the 25th to 75th percentiles, with the centre lines representing the median values. The whiskers reach out to the largest and smallest values, not exceeding 1.5 times the IQR from the upper- and lower-box hinges, respectively. f, Zoomed-in region of the unmixed microtubule structure. Scale bars, 10 µm (c and d); 2 µm (f).
