Light without electricity? Glowing algae could make it possible

CU Boulder researchers have developed 3D-printable hydrogel materials embedded with living bioluminescent algae (Pyrocystis lunula) that can produce sustained light without electricity. By exposing the algae to acidic (pH 4) or basic (pH 10) chemical solutions, they triggered light production lasting up to 25 minutes — a first for sustained bioluminescence. Structures printed with the algae retained 75% brightness after four weeks. Potential applications include lighting for autonomous robots in dark environments, water quality sensors that glow in the presence of toxins, and carbon-storing light sources.