Fig. 3: Dielectric permittivity mapping of coexisting phases across PEG-dextran and glycinin phase diagrams.

a Sketch of the PEG-dextran phase diagram, see ref. ⁴⁴ for experimental values. Crosses (1–2) represent homogeneous PEG-dextran solutions. Black dots indicate the total polymer concentration of the tested phase-separated mixtures. The binodal is shown by a black curve and grey dotted lines represent the tie lines. The endpoints of the tie lines indicate the dextran-rich phase compositions (crosses 3–6) and the PEG-rich phase compositions (7–10). b Permittivities of homogeneous and phase separated solutions at different total polymer concentration. The labels next to the data points correspond to the compositions schematically presented in (a), see Fig. S5 for hyperspectral maps and Table S4 for exact compositions. c Phase diagram of glycinin condensation as a function of protein and NaCl concentrations⁶⁸. Grey regions indicate homogeneous mixtures and the green region denotes phase separation (condensate formation). Points 1, 2, and 3 correspond to NaCl concentrations of 12.5, 100, and 400 mM, respectively, at a constant protein concentration of 10 g/L. d Example permittivity maps for glycinin solutions at three NaCl concentrations indicated in (c). Color bar: rescaled permittivity. Scale bars: 10 µm. e Quantified permittivity of all phases at points 1, 2, and 3 in (c, d). Boxplots show median (central line) and interquartile range (box); whiskers extend to the furthest datapoint within 150% of the interquartile range (point 1: n = 3, point 2: n = 9, and point 3: n = 2).