Dai, Chun-Guang Wang, Ji-Long Fu, Ying-Long Zhou, Hong-Ping Song, Qin-Hua Selective and Real-Time Detection of Nitric Oxide by a Two-Photon Fluorescent Probe in Live Cells and Tissue Slices Nitric oxide (NO) is an important signaling molecule involved in many physiological and pathological processes. To understand these NO-mediated processes, it is a key to develop rapid and specific detection methods for NO. In the past 2 decades, numerous excellent fluorescent probes for NO have been designed; however, it still remains limitations such as slow response, low selectivity, and short excitation wavelength (<600 nm). In this Article, a two-photon fluorescent probe, <b>NO-QA5</b>, has been developed with 3-dimethylaminophenyl linking at the 6-position of 5-aminoquinoline as both the active site and prefluorophore for detection of NO. The nonfluorescent <b>NO-QA5</b> can fast react with NO via a diazonium intermediate to generate two azoic regioisomers, one of which exhibits intramolecular charge transfer (ICT) emission, and two-photon absorption behavior (δΦ = 57 GM), giving a turn-on fluorescence rapid response. The sensing reaction is pH-insensitive in the range of 6–11 and highly selective and well sensitive (LOD = 15 nM), possible undergoing the same intermediate diazonium with the reaction under diazotization condition (NaNO<sub>2</sub>/HCl). Also, as a nitrite fluorescent probe <b>NO-QA5</b> exhibits highly sensitive (LOD = 7 nM). Therefore, <b>NO-QA5</b> can serve as a dual functional fluorescent probe for NO and NO<sub>2</sub><sup>–</sup>. Furthermore, <b>NO-QA5</b> as a specific imaging agent has been demonstrated by achieving both exogenous and endogenous detections of NO in living cells under both one- and two-photon excitation and high resolution in tissue slices under two-photon excitation. GM;exhibits intramolecular charge transfer;detection;probe NO-QA 5 exhibits;Tissue Slices Nitric oxide;diazonium;NO-QA 5;nM;LOD;response;two-photon excitation;ICT;nonfluorescent NO-QA 5 2017-09-11
    https://acs.figshare.com/articles/journal_contribution/Selective_and_Real-Time_Detection_of_Nitric_Oxide_by_a_Two-Photon_Fluorescent_Probe_in_Live_Cells_and_Tissue_Slices/5434912
10.1021/acs.analchem.7b02680.s001