Figure 3

Different regimes of protein accumulation at liquid edge obtained by slowing down the evaporation kinetics. Variation in Raman intensity of the 750 cm⁻¹ signal of 100 μM cytC as obtained by radial Raman mapping (15 μm stepped) from the liquid edge position (0 μm) toward the solution phase at 25 °C (A) and 5 °C (B). Measurements are repeated at different times after the formation of the first liquid edge phase followed by adjusting the temperature at 25 °C or at 5 °C (defined as t = 0). (C) Raman intensity of the 750 cm⁻¹ signal at the liquid edge monitored by repeated acquisitions over a total of 10 min at T = 25 °C and of 60 min at T = 5 °C. Values represent the average of 3 random points of the liquid edge from 3 replicates. The relative standard deviation (RSD) on Raman intensity is 5%. (D) Comparison between Raman profiles of 100 μM cytC at the liquid edge site collected during 60 min at 5 °C and averaged over 165 accumulations (red line) and during 5 min at 25 °C and averaged over 10 accumulations (black line). Inset: enlargement of the 1100–1280 cm⁻¹ spectral region to highlight the intensity and quality differences between the two profiles. See Supplementary Fig. S5 for an analogous comparison on HSA.