Fig. 3: High-resolution photo-patterned formation within the hydrogel, induced by exposure to 445 nm light, showcasing the precise control over spatiotemporal scales at the micron level.

a Spatial heterogeneity of ALYDS-hydrogel patterned by photomasks. b Fluorescence microscope images showcasing a pattern formed on the hydrogel surface through the thiol-ene reaction, utilizing a photomask and 30 min of light exposure. Scale bars represent 100 μm. c Stress-relaxation measurements of the ALYDS hydrogel were performed using atomic force microscopy (AFM). The hydrogel in illuminated region B relaxed faster than in non-illuminated region A. The inset (image) shows the τ’_1/2 and 1-F_p/F_max of the hydrogel. n = 7 per group from 3 independent hydrogels (dark, light). d Illustration of the ALYDS hydrogel’s stress relaxation rates under alternating light (5 mW/cm²) and dark conditions by rheology. The gray area indicates a resting period of 6000 s. e Graph depicting the cyclic stress relaxation behavior (τ_1/2) of the ALYDS hydrogels under various conditions, as measured by rheology. Each cycle involved applying a 15% strain to the hydrogel for 3000 s at an intensity of 20 mW/cm², followed by a 6000-s recovery period in darkness. This process was repeated over five cycles. n = 3 per group from 3 independent hydrogels. The data (c, e) are present as mean values ± S.D.