Fig. 2
a The 3D ear cartilage-shaped template printed by an FDM 3D printer. b The PDMS negative mold for the production of the 3D ear cartilage-shaped hydrogel collector. c 3D ear cartilage-shaped hydrogel collector made of a mixture of alginate and gelatin. d Strain–stress curve of the 4 specimens with the different mixing ratios of alginate and gelatin. e Young's modulus of the 4 specimens and the range of Young’s modulus of native ear cartilage (gray region). All scale bars are 1 cm