AUTHOR=Weber Maria, Yamada Namiko, Tian Xue, Bull Steven D., Minoshima Masafumi, Kikuchi Kazuya, Mackenzie Amanda B., James Tony D. TITLE=Sensing Peroxynitrite in Different Organelles of Murine RAW264.7 Macrophages With Coumarin-Based Fluorescent Probes JOURNAL=Frontiers in Chemistry VOLUME=8 YEAR=2020 URL=https://www.frontiersin.org/articles/10.3389/fchem.2020.00039 DOI=10.3389/fchem.2020.00039 ISSN=2296-2646 ABSTRACT=The elucidation of biological processes involving reactive oxygen species (ROS) facilitates a better understanding of the underlying progression of non-communicable diseases. Fluorescent probes are a powerful tool to study various ROS and have the potential to become essential diagnostic tools. We have developed a series of coumarin fluorescent probes for the selective and sensitive detection of peroxynitrite (ONOO), a key ROS. Coumarin based probes exhibit good photostability, large Stokes shift and high quantum yields. The three ratiometric probes all contain a boronate ester motif for the detection of ONOO and a distinctive organelle targeting group. The study of ONOO generation in a particular organelle will allow more precise disease profiling. Hence, targeting groups for the mitochondria, lysosome and endoplasmic reticulum were introduced into a coumarin scaffold. The three ratiometric probes displayed sensitive and selective detection of ONOO over other ROS species. All three coumarin probes were evaluated in murine RAW264.7 macrophages for detection of basal and stimulated ONOO formation.