Fig. 3.

a) Photopolymerized oxime-based hydrogels can be partially crosslinked by limiting UV exposure. Subsequent photomasked irradiation dictates the location and extent of additional crosslinking. b) Storage modulus evolution of hydrogel solutions increases in response to an initial 10 s of UV exposure (10 mW/cm²), followed by 3 successive pulsed light exposures (5 s each). Purple lines denote times of UV exposure. c) Hydrogel after exposure to UV light through a parallel-line photomask. Opaque regions correspond to areas of NPPOC cleavage and oxime ligation, while dark regions correspond to the unreacted polymer solution (scale bar = 1 mm). d) Brightfield microscope image of a hydrogel patterned to display light 25 μm-wide sol regions dispersed throughout the dark gel (scale bar = 100 μm).