In-situ photopolymerization of monodisperse and discoid oxidized methacrylated alginate microgels in a microfluidic channel

We present a simple microfluidic technique to in-situ photopolymerize (by 365 nm ultraviolet) monodisperse oxidized methacrylated alginate (OMA) microgels using a photoinitiator (VA-086). By this technique, we generated monodisperse sphericalOMA beads and discoid non-spherical beads with better shape consistency than ionic crosslinking methods do. We found that a high monomer concentration (8 w/v%), a high photoinitiator concentration (1.5w/v %), and absence of oxygen are critical factors to cure OMA microgels. This photopolymerizing method is an alternative to current methods to form alginate microgels and is a simpler approach to generatenon-spherical alginate microgels.