A Bioluminescent Probe for Imaging Endogenous Peroxynitrite in Living Cells and Mice

Peroxynitrite (ONOO–), an extremely reactive nitrogen species (RNS), is implicated in diverse pathophysiological conditions, including cancer, neurodegenerative diseases, and inflammation. Sensing and imaging of ONOO– in living systems remains challenging due to the high autofluorescence and the limited light penetration depth. In this work, we developed a bioluminescent probe BP-PN, based on luciferase–luciferin pairs and the ONOO–-responded group α-ketoamide, for highly sensitive detection and imaging of endogenous ONOO– in living cells and mice for the first time. Attributed to the BL without external excitation, the probe BP-PN exhibits a high signal-to-noise ratio with relatively low autofluorescence. Furthermore, we examine the application of the probe BP-PN using the mice model of inflammation, and BP-PN shows high sensitivity for imaging endogenous ONOO– in inflamed mice. This newly developed bioluminescent probe would be a potentially useful tool for in vivo imaging of ONOO– in wider physiological and pathological processes.