Photo electron/energy transfer-reversible addition–fragmentation
chain transfer (PET-RAFT) has emerged as a powerful reversible-deactivation
radical polymerization technique, enabling oxygen-tolerant polymerizations
with exquisite spatiotemporal control through irradiation with visible
light. In contrast to traditional free radical photo-polymerization,
which often requires the use of DNA-damaging UV irradiation, PET-RAFT
offers a more cytocompatible alternative for the preparation of polymeric
materials in cell culture environments. Herein, we report the use
of PET-RAFT for the fabrication of self-healing hydrogels using commercially
available monomers, reaching high monomer conversions and cell encapsulation
efficiencies. Our hydrogels showed the expected rheological and mechanical
properties for the systems considered, together with excellent cytocompatibility
and spatiotemporal control over the polymerization process. Moreover,
hydrogels prepared through this method could be cut and healed again
by simply adding further monomer and irradiating the system with visible
light, even in the presence of mammalian cells. This study demonstrates
for the first time the potential of PET-RAFT polymerization as a viable
methodology for the synthesis of self-healing hydrogel scaffolds for
cell encapsulation.