A mitochondria-targeted chemiluminescent probe for detection of hydrogen sulfide in cancer cells, human serum and in vivo

Hydrogen sulfide (H(2)S) as a critical messenger molecule plays vital roles in regular cell function. However, abnormal levels of H(2)S, especially mitochondrial H(2)S, are directly correlated with the formation of pathological states including neurodegenerative diseases, cardiovascular disorders, and cancer. Thus, monitoring fluxes of mitochondrial H(2)S concentrations both in vitro and in vivo with high selectivity and sensitivity is crucial. In this direction, herein we developed the first ever example of a mitochondria-targeted and H(2)S-responsive new generation 1,2-dioxetane-based chemiluminescent probe (MCH). Chemiluminescent probes offer unique advantages compared to conventional fluorophores as they do not require external light irradiation to emit light. MCH exhibited a dramatic turn-on response in its luminescence signal upon reacting with H(2)S with high selectivity. It was used to detect H(2)S activity in different biological systems ranging from cancerous cells to human serum and tumor-bearing mice. We anticipate that MCH will pave the way for development of new organelle-targeted chemiluminescence agents towards imaging of different analytes in various biological models.