The current progress, design principles in bioimaging and therapeutic applications, and future perspectives of various chemiluminescent platforms are reviewed.

This perspective article aims to introduce the design principles and recognition strategies of small-molecule fluorescent probes which are applied for the detection of gas signaling molecules including NO, CO and H2S in biological systems.

Singlet oxygen ( 1 O 2 ) plays a vital role in metabolism. However, because of its extremely high reactivity and short-lived state, the in vivo detection of 1 O 2 is challenging. To address this issue, for the first time, we herein constructed a nearinfrared (NIR) chemiluminescent probe (CL-SO) by caging the precursor of phenoxy-dioxetane scaffolds and a dicyanomethylchromone acceptor for selective 1 O 2 detection. This probe can detect 1 O 2 in vitro with a tremendous turn-on chemiluminescence signal in the NIR region (700 nm) and image intracellular 1 O 2 produced by the photosensitizer during the simulated action of photodynamic therapy (PDT). Notably, 1 O 2 level changes in the abdominal cavity and tumor of the various mice model under different stimulations and PDT action were effectively monitored by CL-SO, providing a novel chemiluminescence imaging platform to explore 1 O 2 generation in PDT-associated applications.