Summary: This Cell Intracellular Fluorimetric Hydrogen Peroxide Assay Kit uses our unique Green Peroxide Sensor to quantify hydrogen peroxide in live cells. Green peroxide sensor is cellpermeable, and generates the green fluorescence when it reacts with hydrogen peroxide. This kit provides a sensitive tool to monitor hydrogen peroxide level in living cells. The kit is also optimized with "mix and read" assay format for solution based assay. It provides a sensitive, one-step fluorimetric assay to detect as little as 0.3 nanomoles of H2O2 in a 100 µL assay volume (3 µM). The assay can be performed in a convenient 96-well or 384-well microtiterplate format. Its signal can be easily read by either a fluorescence microplate reader at Ex/Em = 490/520 nm for H2O2 detection in solution or a fluorescence microscopy and a flow cytometry for live cell H2O2 detection.