Single Fluorescent Probe Distinguishes Hydrogen Peroxide and Nitric Oxide in Cell Imaging

In combination with synthetic fluorescent probes, fluorescence microscopy has emerged as a powerful technique to investigate the production, localization, trafficking, and function of biomolecules in living systems in a noninvasive manner. Prompted by our interest in providing a molecular tool to disentangle the complicated interrelationship between H2O2 and NO in the signal transduction and oxidative pathways, our laboratory has developed a single fluorescent probe, FP H2O2 NO, that can report H2O2, NO, and H2O2/NO with three different sets of fluorescence signal patterns. In this chapter, we provide essential information about the probe FP-H2O2-NO in order to assist researchers interested to apply our probe to investigate H2O2 and NO biology. We describe the use of FP H2O2 NO with the representative examples of imaging both exogenous and endogenous H2O2 and NO in live He la and RAW 264.7 macrophage cells by fluorescence microscopy.