Firefly-mimicking intensive and long-lasting chemiluminescence hydrogels.

Most known chemiluminescence (CL) reactions exhibit flash-type light emission. Great efforts have been devoted to the development of CL systems that emit light with high intensity and long-lasting time. However, a long-lasting CL system that can last for hundreds of hours is yet-to-be-demonstrated. Here we show firefly-mimicking intensive and long-lasting CL hydrogels consisting of chitosan, CL reagent N-(4-aminobutyl)-N-ethylisoluminol (ABEI) and catalyst Co2+. The light emission is even visible to naked eyes and lasts for over 150 h when the hydrogels are mixed with H2O2. This is attributed to slow-diffusion-controlled heterogeneous catalysis. Co2+ located at the skeleton of the hydrogels as an active site catalyzes the decomposition of slowly diffusing H2O2, followed by the reaction with ABEI to generate intensive and long-lasting CL. This mimics firefly bioluminescence system in terms of intensity, duration time and catalytic characteristic, which is of potential applications in cold light sources, bioassays, biosensors and biological imaging.Great efforts have been devoted to the development of chemiluminescence systems that emit light with high intensity over long periods of time. Here the authors show, firefly-mimicking intensive and long-lasting chemiluminescence hydrogels consisting of chitosan, N-(4-aminobutyl)-N-ethylisoluminol (ABEI) and catalyst Co2+.