Visible Light as a Benign Stimulus for Additive Manufacturing of Hydrogels

Light as an energy source has enabled transformative technologies in imaging, lithography, adhesives, and 3D printing. Its broad utility arises from the unparalleled spatiotemporal control over chemical transformations that it offers. However, contemporary methods rely on high energy UV light (&lt; 400 nm), which limits biocompatibility due to degradation and attenuation that occurs upon absorption and/or scattering. Excitingly, the recent commercialization of inexpensive light emitting diodes has opened up an avenue to examine mild visible-light induced reactions in the fabrication of biologically relevant scaffolds. This presentation will focus on how the <i>ZAP Group</i> has developed low energy light driven reactions to create macroscopic water-swollen scaffolds (i.e., hydrogels) with unprecedented speed and precision. Specifically, catalyst design principles to enable rapid solidification of photopolymer resins using visible-light will be discussed, along with their utility and optimization in high resolution additive manufacturing.