biostudies-literatureRapp TLU.S. Department of Health &amp; Human Services | NIH | National Institute of General Medical SciencesWashington Research FoundationNIGMS NIH HHSNational Science Foundation5250https://www.ebi.ac.uk/biostudies/studies/S-EPMC10462736biostudies-literatureUnknown14(1)Photodynamic hydrogel biomaterials have demonstrated great potential for user-triggered therapeutic release, patterned organoid development, and four-dimensional control over advanced cell fates in vitro. Current photosensitive materials are constrained by their reliance on high-energy ultraviolet light (<400 nm) that offers poor tissue penetrance and limits access to the broader visible spectrum. Here, we report a family of three photolabile material crosslinkers that respond rapidly and with unique tricolor wavelength-selectivity to low-energy visible light (400-617 nm). We show that when mixed with multifunctional poly(ethylene glycol) macromolecular precursors, ruthenium polypyridyl- and ortho-nitrobenzyl (oNB)-based crosslinkers yield cytocompatible biomaterials that can undergo spatiNature communicationsTricolor visible wavelength-selective photodegradable hydrogel biomaterials.PMC10462736R35GM138036N/ADMR 1652141DMR 1807398R35 GM138036Rapp TLDeForest CAfalseTricolor visible wavelength-selective photodegradable hydrogel biomaterials.Photodynamic hydrogel biomaterials have demonstrated great potential for user-triggered therapeutic release, patterned organoid development, and four-dimensional control over advanced cell fates in vitro. Current photosensitive materials are constrained by their reliance on high-energy ultraviolet light (<400 nm) that offers poor tissue penetrance and limits access to the broader visible spectrum. Here, we report a family of three photolabile material crosslinkers that respond rapidly and with unique tricolor wavelength-selectivity to low-energy visible light (400-617 nm). We show that when mixed with multifunctional poly(ethylene glycol) macromolecular precursors, ruthenium polypyridyl- and ortho-nitrobenzyl (oNB)-based crosslinkers yield cytocompatible biomaterials that can undergo spati2023-01-01T00:00:00Z2023 Aug2026-06-04T06:50:37.735Z2025-04-06T14:39:17.796ZS-EPMC104627363764070710.1038/s41467-023-40805-w