2024 AIChE Annual Meeting
Processing and Characterization of Alginate Tubes for Use in Vascular Tissue Grafting
Alginate is a naturally occurring polysaccharide derived from brown algae, which is normally extracted into a sodium alginate (NaAlg) form. NaAlg will crosslink when reacted with a bivalent cation. This reaction gives NaAlg several distinct features allowing for use in biomedical applications such as wound dressings, drug delivery, and tissue engineering. To this end, shear rheology was used to characterize the viscosity of NaAlg to assess the processability of NaAlg into tubes for use in cardiovascular grafting. A co-flow setup was utilized to fabricate NaAlg tubes by pumping NaAlg around an 8-gauge flow of aqueous CaCl2 into a CaCl2 bath for complete crosslinking. The data was used to construct a phase-shift diagram documenting several hundred extrusion points, outlining the boundaries for successful extrusion of NaAlg tubes. The tubes were characterized by burst pressure and tensile strength tests to measure the mechanical properties of the material. This work aims to establish relationships between rheological properties of different concentration alginate solutions, extrusion limits of NaAlg tubes, and their subsequent mechanical properties, thereby defining process-structure-property-performance relationships for NaAlg.