Investigation of the Relationship Between H₂O₂ and HClO in Living Cells by a Bifunctional, Dual-ratiometric Responsive Fluorescent Probe

Abstract

As two important reactive oxygen species, hydrogen peroxide (H 2 O 2 ) and hypochlorous acid (HClO) play vital roles in many physiological and pathological processes. However, the relationship between these two species is seldom investigated, in part, because of the lack of robust molecular tools that can simultaneously visualize HClO and H 2 O 2 in biosystems. In this work, we present a design strategy to construct a single fluorescent probe that can detect H 2 O 2 and HClO by simultaneously monitoring two distinct detection channels. In the design, one phenothiazine-based coumarin serves as a chromophore and sensor for HClO, while a second coumarin precursor containing a boronate ester acts as a sensor for H 2 O 2 . After a head-to-head screening of three candidates differing in their coumarin precursor moieties, probe CSU1 was found to have the optimal characteristics. As shown experimentally, it is able to detect them selectively and sensitively to generate distinct fluorescence signals and patterns in living cells. Furthermore, the endogenous generation of HClO from H 2 O 2 and Cl − catalyzed by myeloperoxidase enzyme in living cells can be clearly monitored by the probe. These studies demonstrate the potential of the probe as a powerful tool to investigate the interplay of HClO and H 2 O 2 in oxidative stress.

Inner filter effect between upconversion nanoparticles and Fe(ii)–1,10-phenanthroline complex for the detection of Sn(ii) and ascorbic acid (AA)

“…6 Han et al constructed a multifunctional uorescent probe capable of detecting H 2 O 2 and cholesterol by simultaneously monitoring two different detection channels. 7 We found that both Sn(II) and AA can reduce Fe(III) to Fe(II) without further reducing Fe(II) to Fe, so the platform designed by us can be used to detect Sn(II) and AA.…”

Recent Progress in Organic Small-Molecule Fluorescent Probe Detection of Hydrogen Peroxide

“…Wang’s group constructed a dual-ratiometric fluorescent probe (example 18) that can simultaneously detect HClO and H 2 O 2 by two channels ( Figure 23 ). 20 In probe 18, coumarin was the fluorescent parent, and the recognition group of HClO and H 2 O 2 was skillfully combined. The probe had high selectivity and sensitivity to H 2 O 2 and HClO and meanwhile could be used to monitor the generation of endogenous H 2 O 2 and HClO.…”

A BODIPY‐Diaminomaleonitrile Based Water‐Soluble Fluorescent Probe for Selective “Off‐On” Detection of Hypochlorite**

“…Fluorescent probes have been widely used in ClO À fluorescence imaging in recent years due to their advantages of simplicity, high sensitivity, high selectivity and real-time monitoring. [13][14][15][16][17][18][19][20][21][22] Various fluorophores used to design ClO À fluorescent probes mainly include coumarin, [23][24][25] rhodamine, [26][27][28] cyanine, [29][30][31] 1,8-naphthalimide [32][33] and boron-dipyrromethene (BODIPY). [34][35] Among them, BODIPY is often used in the design of in vivo imaging probes due to its excellent photostability, low cytotoxicity, polarity and pH insensitivity, and chemical robustness.…”