Printability Of Hydrogel Composites Using Extrusion-Based 3D Printing And Post-Processing With Calcium Chloride

of Composites Using 3D Abstract Bioprinting is a promising technique in processing hydrogels to fabricate different matrices with active agents in the pharmaceutical industry. This study investigated the printability of gelatin-algi-nate hydrogel by extrusion-based 3D printing. 3D printed structures were thenpost-processed with calcium chloride solution to improve surface smoothness and gel strength. In this study, we aimed to fabricate bioscaffold using natural biopolymers with different ratios of Gelatin and Alginate (G/A) to deliver pharmaceutical or supplemental ingredients. The G/A influenced the rheology properties, which were strongly correlated to the 3D printability and deformability of the materials. There was a shear-thinning behavior for all three materials tested with G/A of 1:4, 1:1, and 4:1. All materials showed the magnitude of G’ higher than G”, and the loss factor tan δ<1. Furthermore, the viscoelastic properties of materials with G/A 1:1 and 1:4 were within the range of the loss factor tan δ 0.3 to 0.5, which was poten tially 3D printable. The best 3D printability and the least deformation were both observed for G/A of 1:1, making it superior than G/A 1:4 and 4:1 for 3D printing purposes. Also, the soaking time for post-pro-cessing also affected the surface smoothness and gel strength. When 3D printed matrices were immersed in CaCl 2 solution (0.1M) for a longer time, the surface smoothness was highly improved, but the deformation also increased. Overall, the material with G/A ratio 1:1 and post-processed with CaCl 2 for a shorter length of time should have a huge potential to be used for extrusion-based 3D printing for delivering pharmaceutical and supplemental ingredients.