Highly Selective and Sensitive Two-Photon Fluorescence Probe for Endogenous Peroxynitrite Detection and Its Applications in Living Cells and Tissues.

A new two-photon fluorescence probe for endogenous peroxynitrite (ONOO(-)) detection was designed and synthesized. The probe exhibits good selectivity and sensitivity for ONOO(-) in phosphate-buffered saline solution with a low detection limit (3.5 × 10(-8) M). Furthermore, the probe displays good performance in detecting endogenous ONOO(-), not only in RAW 264.7 cells but also in rat hippocampal tissue, with a high two-photon cross-section value (δ ≈ 100 GM) at a deep depth of 120 μm.