Fig. 3: Rheological behavior and mechanical properties of hydrogel using ZnO NPs of different morphologies.

a Comparison of the viscosity of different morphologies of ZnO with the shear rate from 0.1 to 100 s⁻¹. Inset: Photographs of the injectability of GelMA/str-ZnO hydrogel through the needle. b Schematic of the effect of different morphology of ZnO on the rheological behavior and mechanical properties of hydrogels. c Left: TEM images; Middle: Scheme of NPs; Right: Curvature distribution. a for the apical endpoint, b for the blunt endpoint. d Apical mean curvatures of sph-ZnO and str-ZnO. Data were presented as the mean ± SD (n = 3 independent experiments). e Trajectories of sph-ZnO in hydrogel at a syringe pump pressure of 100 µL/min. f Trajectories of str-ZnO in hydrogel at a syringe pump pressure of 100 µL/min. g The diffusion coefficient of sph-ZnO and str-ZnO in hydrogel. Data were presented as the mean ± SD (n = 5 independent samples). h Comparison of strain at the flow point between different morphologies of ZnO. i Comparison of storage modulus between different morphologies of ZnO. Inset: Schematic of oscillatory rheological testing. j Comparison of compressive modulus between different morphologies of ZnO. Data are presented as the mean ± SD (n = 3 independent experiments). *P < 0.05, **P < 0.01, ***P < 0.001, and ****P < 0.0001. Statistical comparisons were performed using the unpaired two-sided Student’s t-test in d, g, j. Source data are provided as a Source Data file.