Light at 617 nm, 530 nm, and 405 nm at 5, 10, and 20 mW cm -2 were used for the QY determination. As expected, faster photocleavage for each compound accompanied higher light intensities. When extent of photolysis was normalized to total light dosage (i.e., the product of intensity and exposure time), cleavage traces collapsed onto a single curve for each species (Fig. ). Rubpy has the highest QY of the three (0.29 ± 0.04), consistent with prior reports for Ru(bpy)2L2 complexes under visible light irradiation . Rubiq's QY (0.016 ± 0.009) was found to be lower than that of Rubpy, due to the bathochromic shift decreasing intersystem crossover efficiency into the metal-centered antibonding orbital . Though oNB has a very low QY at 405 nm (0.004 ± 0.003), its higher molar absorptivity enables photocleavage under visible irradiation with reasonable efficiency. Finding photolysis to be complete for all three crosslinkers within 30 minutes at 10 mW cm -2 intensity (Fig. ), these irradiation conditions were used for all gel degradation experiments. Significant color change accompanied photolysis for each compound, particularly for Rubiq, providing a useful handle for qualitative crosslinker cleavage determination in hydrogel formulations (Fig. ). ). Results highlight that the gels can be photodegraded in a visible wavelength-selective manner as designed.