Chemical Stimulation Sustains Bioluminescence of Living Light Materials
Bioluminescence offers a powerful tool for real-time, label-free sensing for living materials. However, conventional approaches often rely on mechanical stimulation, which is difficult to standardize, spatially localize, and sustain over time. Here, we introduce a chemical strategy to stimulate and sustain bioluminescence in the marine dinoflagellate Pyrocystis lunula, enabling the fabrication of robust, adaptive, light-emitting living materials. By embedding P. lunula into 3D-printed, ionically crosslinked alginate hydrogel scaffolds, we engineered architecturally stable living materials with long-term cellular retention, viability, and light-emitting capacity. Exposure to acidic and basic environments enabled chemically resolved sensing and response via distinct bioluminescent signatures: acid triggers intense, localized, and persistent emission up to 25 minutes, while base induces a diffuse, biphasic emission indicative of cellular stress. Notably, coupling chemical with mechanical stimulation yields a synergistic enhancement of bioluminescence, achieving significantly greater amplitude and duration of light emission without compromising cell reactivity. Longitudinal studies over four weeks demonstrated that our living-light materials retain responsiveness and structural integrity across repeated stimulation cycles, overcoming the limitations of single-use mechanical activation. Together, these findings establish a robust new platform for programmable, light-emitting living materials with applications in biosensing, soft robotics, and environmental monitoring.