2.3 Rheology of A-SA-Gel hydrogel
The rheological properties of the A-SA-Gel hydrogel were analyzed by using a rotational rheometer (DHR-3, TA Instruments, USA). A cone plate geometry was adopted according to the manufacturer’s protocol, in which the diameter and interpolate gap were 30 and 1 mm, respectively. The steady-shear rate sweeps were conducted on the hydrogel sample, which was carefully loaded onto the plate fixture without the air bubbles at room temperature. Before performing the shear test, all samples were held for 15 min to eliminate thermal and shear histories. The storage and loss modulus of the hydrogel samples were measured as a function of strain amplitude sweep test and frequency.