Nanocellulose and Elastin Act as Plasticizers of Electrospun Bioinspired Scaffolds

In this work, we produced cross-linked electrospun hybrid scaffolds composed of gelatin/poly-d,l-lactide (PDLLA), gelatin/PDLLA/nanocellulose, and gelatin/PDLLA/cellulose nanocrystals/elastin. Fourier-transform infrared spectroscopy, X-ray diffraction, and high-performance liquid chromatography demonstrated the complete embedding of each component in the hybrid scaffolds. The degree of cross-linking was quantified by the 2,4,6-trinitrobenzenesulfonic acid assay, and attenuated total reflectance spectroscopy revealed the effectiveness of the cross-linking reaction. Notably, the interconnected porous structure revealed in uncross-linked scaffolds persisted even after cross-linking. Scaffolds were characterized in water through their contact angle showing total wettability. We investigated their mechanical properties by uniaxial tensile testing, which showed that even in the dry state, nanocellulose- and elastin-containing scaffolds exhibit higher elongation at rupture compared to those with pure gelatin/PDLLA. Therefore, we succeeded in tuning the toughness of the scaffolds by modulating the composition. In order to use scaffolds as medical devices, we assayed fibroblasts on scaffold extraction media, indicating that they were noncytotoxic. Finally, the attachment and proliferation of fibroblasts on the surface of different scaffolds were evaluated.