Adbioink offers methacrylated hyaluronic acid bioink. Hyaluronic acid (HA) [α-1,4-D-glucuronic acid-β-1,3-N-acetyl-D glucosamine]n, is a naturally occurring high molecular weight hydrophilic glycosaminoglycan. It is an abundant polymer in the extracellular matrix, where it provides mechanical support. Hyaluronan also provides to tissue hydrodynamics, movement and proliferation of cells, and participates in a number of cell surface receptor interactions. It is a cell-friendly material and oftenly used natural polymer for cell scaffolding.

The chemical structure of hyaluronic acid allows (primary) hydroxyl groups to be easily replaced by esterification. Modification with methacrylate groups followed by the addition of a photoinitiator leads to polymerization upon UV exposure, resulting in network formation. Methacrylated hyaluronic acid (HaMA) is more resistant to degradation and more rigid than non-derived hyaluronic acid hydrogels, while retaining its biocompatibility. Methacrylation increases the final mechanical strength of hyaluronic acid and this results in hyaluronic acid-based hydrogels that can be 3D bioprinted. These hydrogels shows good primary cell survival and superb spontaneous osteogenic differentiation in vitro. HaMA-based hydrogels with intrinsic osteogenicity are promising scaffold materials for application in 3D printed, tissue engineered bone replacements.