Fig. 4
From: Measurement of nanoscale three-dimensional diffusion in the interior of living cells by STED-FCS
SPLIT-FLCS of tubulin-EGFP in the cytoplasm of live cells. a Representative filtered ACFs of tubulin-EGFP in the cytoplasm of HeLa cells at a STED power of 50 mW for different values of the parameter r 1 (r 1 = 11w 0, 4w 0, 2w 0, w 0, respectively, from top to bottom). Shown are two experimental measurements taken as representative of fast (left) and slow (right) diffusion, respectively. Solid lines are a fit of the data to Eq. (15). Residuals are shown on the right axis. The image of a cell is shown in the inset (scale bar 10 μm). b Transit time t D and apparent diffusion coefficient D for different spatial scales, obtained as the average of single-point measurements in the cytoplasm of HeLa cells (n = 32, mean ± s.d.). The solid red line is a linear fit to the data. The dashed line represents a Brownian motion with D = 25 μm2 s−1. c Transit time t D at different spatial scales for all the single-point measurements. The data have been grouped into three categories depending on the value of transit time t D measured at the smallest spatial scale (w = 104 nm): t D < 0.4 ms (blue), 0.4 ms < t D < 0.7 ms (green), t D > 0.7 ms (black). The dashed lines are linear fits of the average of each group
