Fig. 2

Casein hydrogels characterization. (a) SEM images of different hydrogels, scale bar: 100 μm; (b) Pore size distribution of different hydrogels; (c) FTIR spectrum of casein powder and casein hydrogels; (d) Rheology analyses, gelation time and storage modulus of casein solution with different concentrations (5%, 10%, 15%), upon exposure to visible light at 450 nm (n = 3); (e) Gelation time of casein hydrogels with different light intensity at 450 nm; (f) Compression modulus of casein solution concentrations (5%, 10%, 15%) (n = 3), (g) Mass swelling ratio with casein hydrogels (5%, 10%, 15%) at different time point (mean ± SD; n = 3); (h) Snowflake, mesh and eagle patterned hydrogels prepared by 3D printing