Fig. 4.

Microstructure analysis of human bone ECM hydrogels using scanning electron microscope (SEM) and micro-computed tomography (μ-CT). (a) SEM images of cross-sections of lyophilised ECM hydrogels were observed by SEM (scale bar = 300 μm), showing the presence of porous and fibrous structures in all types of ECM hydrogels. (b) 3-dimensional visualization of the ECM hydrogel structure using μ-CT demonstrates the porous nature of the hydrogels. (c) Measurement of pore sizes in ECM hydrogels using ImageJ software reveals no significant differences between the hydrogels (n = 3). Statistical significance was determined using a two-way ANOVA test with Tukey's multiple comparisons test (∗p < 0.05 ∗∗p < 0.005 ∗∗∗p < 0.0005∗∗∗∗). Data represent mean ± SD, N = 4.