FIGURE 3.

Preparation and characterization of granular gel. (a) HA‐LA microgels were assembled by silver ions through coordination to form bulk granular gels, which were stable in water. (b) The SEM image of dry granular gel (scale bar: 20 μm). (c) The wet granular gel observed by stereomicroscope (scale bar: 200 μm). (d) SEM image processing to show gap among microgels at dry state. (e) Image processing to show spaces among microgels at wet state (pink lines were used to draw the outline of the microspheres; the blue area indicated the gap among microgels). (f) Water absorption of granular gel prepared with different concentrations of Ag⁺. (g) The rheological test confirms that it is a solid‐state hydrogel. (h) The rheological test showed yield when the shear force reaches a certain degree. (i) The rheological test showed shear‐thinning feature. (j) Evaluation of self‐recovery of the granular gels under alternating strains of 1% and 100%. (k) The extrusion test and the stability of extruded filament in PBS, and the general observation of extruded granular gel with solid state. (l) The SEM images of extruded filament with densely packed microgels (scale bar: 100 μm for left, 20 μm for right). The data represent the mean ± SD. * indicates that these data showed significant differences with other data. HA‐LA, hyaluronic acid‐g‐lipoic acid; SEM, scanning electron microscopy