Ji, Jin J.Rosenzweig, NitsaJones, ImanieRosenzweig, Zeev2021-04-192021-04-192002-07-01Ji, Jin J.; Rosenzweig, Nitsa; Jones, Imanie; Rosenzweig, Zeev; Novel fluorescent oxygen indicator for intracellular oxygen measurements; J. of Biomedical Optics, 7(3), (2002); https://www.spiedigitallibrary.org/journals/journal-of-biomedical-optics/volume-7/issue-03/0000/Novel-fluorescent-oxygen-indicator-for-intracellular-oxygen-measurements/10.1117/1.1483082.fullhttps://doi.org/10.1117/1.1483082http://hdl.handle.net/11603/21354Intracellular oxygen concentration is of primary importance in determining numerous physiological and pathological processes in biological systems. In this paper, we describe the application of the oxygen sensing indicator, ruthenium dibipyridine 4-(19-pyrenyl)-2,28-bipyridine chloride [Ru(bpy-pyr)(bpy)₂], for molecular oxygen measurement in J774 murine macrophages. Ru(bpy-pyr)(bpy)₂ exhibits strong visible absorption, efficient fluorescence, long excited state lifetime, large Stokes shift, and high photoand chemical stability. The fluorescence of Ru(bpy-pyr)(bpy)₂ is efficiently quenched by molecular oxygen. It is 13 fold higher in a nitrogenated solution than in an oxygenated one. The dye passively permeates into cells and maintains its oxygen sensitivity for at least 5 h when the cells are stored in a phosphate buffered saline solution at pH 7.4. The oxygen sensitivity, photostability, and chemical stability of the indicator and the effect of hypoxia and hyperoxia on the intracellular oxygen level in single macrophages are discussed.6 pagesen-USThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.©2002 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibitedText