Swelling rate.
Hydrogel swelling rate characterizes its capacity to absorb aqueous
fluids in an in vivo environment, which may be directly
associated to the exchange of waste and nutrients. (Peng, 2019).
Hydrogel samples were immersed in water and weighed to obtain the four
SR curves (Figure 5 ). As a result, each hydrogel swelled a high
volume of water during the first hour, independently of the polymeric
composition. Then, water absorption slowed down reaching an equilibrium
after 4 hours.
Starch-PVA hydrogel, consistent with its rigid appearance and smaller
channel diameters, showed lower SR values. On the contrary, starch and
starch-CS hydrogels presented similar properties, increasing its weight
approximately five times. In the case of starch hydrogel, a tendency to
lost water in time was observed; this could be related to a loss of
structural integrity (Biduski, 2018). A higher swelling rate, which
doubles the values of the other hydrogels, was observed for
starch-CS-GA. This property is highly convenient for the absorption of
water-dispersed drugs and particles; and also an appropriate feature for
exudate incorporation in tissue engineering applications.