Figure 4. Dependence of the position of the microgel on the applied pressure difference.

(a) Effect of pressure difference on the position of the microgel front tip x_f along the x-axis in the microchannel, plotted at the same degree of confinement D₀/d_c = 2.24 ± 0.01 for the microgels with the Young’s modulus of 2.57 (), 8.26 () and 12.54 kPa () (corresponding to agarose concentration in the microgel of 2, 3, and 4 wt%, respectively). The results are obtained for microgels with corresponding diameters D₀ of 94, 101, and 100 μm, which were passing through the constriction with a diameter d_c of 42, 45 and 45 μm, respectively, at α = 15°. (b) A master curve of the relative microgel position x_f/d_c, plotted as a function of ΔP/E₀. The colors of symbols in (b) are the same as in (a). The black curve shows the result of numerical calculations with a fitting parameter κ = 0.365 (see Supplementary Fig. S7e). Inset shows the data for positive x_f on double-logarithmic scale. Red line with a slope 2.3 demonstrates agreement of data with scaling equations (2) and (6) for the constriction regime (x_f > 0).