Novel Dimethylhydrazine-Derived Spirolactam Fluorescent Chemodosimeter for Tracing Basal Peroxynitrite in Live Cells and Zebrafish

The precise cellular function of peroxynitrite (ONOO–) in biosystems remains elusive, primarily owing to being short of ultrasensitive techniques for monitoring its intracellular distribution. In this work, a novel rhodamine B cyclic 1,2-dimethylhydrazine fluorescent chemodosimeter RDMH-PN for highly specific and ultrasensitive monitoring of basal ONOO– in biosystems was rationally designed. The fluorescence titration experiments demonstrated that RDMH-PN was capable of quantitatively detecting 0–100 nM ONOO– (limit of detection = 0.68 nM). In addition, RDMH-PN has outstanding performances of ultrafast measurement, naked-eye detection, and preeminent selectivity toward ONOO– to accurately detect intracellular basal ONOO–. Finally, it has been confirmed that RDMH-PN could not only map the intracellular basal ONOO– level by inhibition tests but also trace the fluctuations of endogenous and exogenous ONOO– levels with diverse stimulations in live cells and zebrafish