Fig. 2 |.

Characterization of the expansion and contraction behaviour of ferritin crystal-hydrogel hybrids. a, Structural evolution of a ferritin crystal-hydrogel hybrid during the polymerization-expansion-contraction process. Black arrows indicate the addition of different solutions or water to the crystal. The numbered images (i-vi) in the top panels correspond to the selected time points shown as red circles in the bottom panel. The separation between the major ticks of the ruler is 100 μm. b, SAXS profiles of hydrogel-infused ferritin crystals during lattice expansion, plotted against the scattering vector length q. The progression of scattering peaks to lower angles is indicated with grey dashed lines. Peaks corresponding to the original lattice parameters (designated with red asterisks) are visible throughout the process. c, Changes in the unit-cell parameter a during lattice expansion, calculated from the SAXS profiles shown in b. The schematics correspond to the red circles and are drawn to scale. The error bars were determined from the full-widths at halfmaximum of the scattering peaks. d, Expansion and contraction of a single crystal, monitored using SAXS.