Imaging of endogenous hydrogen peroxide during the process of cell mitosis and mouse brain development with a near-infrared ratiometric fluorescent probe.

Hydrogen peroxide (H2O2) is emerging as a new second messenger, which plays vital roles in intracellular signaling, thereby triggering physiological variations in terms of proliferation, differentiation, and migration. As known, cell mitosis has closely association to the intracellular level of H2O2, which contribute to the significant effects on the brain development, especially during the critical period of immaturity. To further investigate the biological roles of endogenous H2O2 in cells mitosis, we develop a near-infrared ratiometric fluorescent probe BCy-PFS for specifically imaging of endogenous H2O2 in cells and in vivo. Employing the probe BCy-PFS, we examine the critical effects of endogenous H2O2 on cells proliferation in live hippo-campal neurons cells, our results provide strong evidences for H2O2 signaling in cell mitosis through growth factor signaling. Furthermore, we successfully demonstrate the close association of endogenous H2O2 level changes with the brain develop-ment at various stages. We envision that this present probe has potential as a promising useful chemical imaging tool for exploring the roles of H2O2 in cell mitosis.