Enhancement of alginate/gelatin/polyvinyl alcohol hydrogels for multi-crosslinked 3D printed blood vessels

Given the significant social and clinical challenges posed by the increasing incidence of cardiovascular diseases (CVDs), the development of small-diameter artificial blood vessels utilizing biomacromolecular materials has emerged as a promising therapeutic strategy for addressing CVDs. In this paper, sodium alginate/gelatin/polyvinyl alcohol (SA/Gel/PVA) porous composite hydrogel ink is firstly prepared by multiple crosslinking method, aiming to solve the problems of poor mechanical properties and unsatisfactory printing effect of small diameter blood vessels. The effect of crosslinking order on the mechanical properties of the materials is explored by adjusting the ratio of SA/Gel/PVA hydrogel. In results, the mechanical strength (>20 %), swelling property (>250 %) and water content (>81 %) of the materials can be improved by appropriate crosslinking method and concentration ratio. Through comprehensive characterization encompassing mechanical properties, moisture content, and microscopic morphology analysis, this study investigates the influence of microscopic pore architecture on the physicochemical characteristics of hybrid hydrogels, aiming to optimize the hydrogel formulation for enhanced performance. Finally, the self-developed 3D printing equipment is utilized to verify the printing feasibility. This study can not only advance the performance of SA/Gel/PVA hydrogel, but also further advance the application of SA/Gel/PVA hydrogel in the field of vessel printing and molding.