Table 2.
Mechanical behavior of fully hydrated HAc-Alg hydrogels, and HAc-Alg/ 30wt% CaP composite hydrogels prepared by mixing and in situ precipitation (n>3).
| Specimen | Swelling ratio (g/g) | Bulk gela | 3D printed porous scaffold | |
|---|---|---|---|---|
| G’ (Pa)b | E (kPa) | σc (kPa)c | ||
| HAc-Alg | 31±2 | 298±58 | 3.3±0.6 | 18.9±2.1 |
| HAc-Alg/30wt% CaP (mixing)d | 28±1 | 502±62 | N.A. | N.A. |
| HAc-Alg/30wt% CaP (in situ precipitation) | 25±1 | 1397±194 | 6.4±1.2 | 35.9±2.9 |
a
hydrogel specimens fabricated by direct casting using a cylindrical mold and assessed by a rheometer,
b
storage modulus at frequency of 1 Hz,
c
maximum stress at compressive strain, ε=0.8,
d
HAc-Alg/ 30wt% CaP ink prepared by mixing CaP with HAc-Alg has very low printability due to high viscosity and inconsistent extrusion behavior; thus, its 3D printed scaffolds could not be fabricated for mechanical tests. HAc-Alg: Hyaluronic acid-alginate, CaP: Calcium phosphate, 3D: Three-dimensional