Chemiluminescence chitosan hydrogels based on the luminol analog L-012 for highly sensitive detection of ROS

Chemiluminescence probes have been widely used in a very broad field including immunoassay or non-immunoassay diagnostic and monitoring techniques as well as biosensors. The luminol analog L012 as a chemiluminescence probe was applied in the detection of reactive oxygen species (ROS). However, the short chemiluminescence time of L012 limits its application in imaging in vivo. In this study, we developed chemiluminescence chitosan hydrogels L012-Cs-Co²⁺ based on a slow-diffusion-controlled heterogeneous catalytic mechanism. The hydrogels can emit strong chemiluminescence in the presence of H₂O₂, which can be observed by naked eyes in the darkroom within 60 min. They also exhibited high sensitivity towards H₂O₂ with the calculated detection limit of 8.7 × 10^-8 M. In addition, it was successfully applied in imaging of H₂O₂ in vivo.