Visible Light Photo-initiators for Biofabrication in Tissue Engineering and Regenerative Medicine Applications

Photo-initiated radical polymerisation which is combining light and photo-initiators to generate radicals for crosslinking photo-polymerisable macromers, has been employed in 3D biofabrication of cell-laden hydrogel constructs. The major advantage of using this technology is the spatio-temporal control over the crosslinking process, as well as being able to fabricate constructs with tailorable physico-mechanical properties. However, most commonly used water-soluble photo-initiator such as Irgacure®2959 (I2959) absorb in the UV region (300-400nm), which can potentially cause cellular DNA damage. In order to address this drawback, our group has focused on the development of alternative photo-initiators that absorb in the visible light region. In addition, we have utilised this newly developed photo-initiators for a number for biofabrication approaches, such as 3D bioassembly, extrusion-based bioplotting and lithography based bioprinting.