Rosellini et al. [23] showed that in vitro degradation
behavior at 37 C of gelatin cross-linked with GA films in
PBS is quite similar to that obtained in PBS collagenase
solution. Electrospun cross-linked samples were immersed
in PBS solution and the extent of hydrolytic degradation
was determined (Fig. 2). It was found that cross-linked
electrospun gelatin fibers took less than 5 min to reach
the equilibrium swelling state (data not shown) and can
uptake as much as 14 times of its initial mass [28]. Gelatin
weight loss occurred rapidly during the first week of incubation,
losing around 50% of the sample initial mass
(Fig. 2a) after approximately 9 days. After 15 days, a residual
mass of 32% remained. Zhou et al. [31] suggested that
gelatin mass loss during in vitro and in vivo degradation
occurs primarily due to solvation and depolymerization of
polymeric chains. It was observed also that electrospun
cross-linked membranes still showed integrity after a week
in vitro degradation (Fig. 2b and c)