3D Printing for Biological Scaffolds using Poly(Ionic Liquid)/Gelatin/Sodium Alginate Ink

The poly(ionic liquid)s (PILs) have attracted a wide range of applications in thermo-responsive materials, carbon materials, catalysis, porous polymers, separation and absorption materials, and biological field due to their favorable tunability and biological functions. However, the applications of PILs in bio-scaffold are rarely studied. In the present work, the ionic liquid (IL) monomer (1-vinyl-3-butylimidazolium chloride, [VBIM]Cl) is cross-linked with other three compounds, respectively, to synthesize three kinds of PILs (PIL1, PIL2, and PIL3). Furthermore, individually cross-linked PILs are added into gelatin (Gel)/sodium alginate (SA) solution aiming to prepare biological inks (bio-inks) for 3D printing. The water absorption, degradation rate, and porosity of the bio-scaffolds are measured to evaluate the physicochemical characteristics, while the PC12 cell line is used to evaluate the biocompatibility of the bio-scaffolds through cell proliferation. These results demonstrate that the biological activity of the bio-scaffold can be varied at the tendency of PIL1 < PIL3 < PIL2, providing a potential prospect for the application of PILs in tissue-engineered bio-scaffolds.