Dansyl-appended Cu^II-complex-based nitroxyl (HNO) sensing with living cell imaging application and DFT studies

Abstract

We introduce herein, a novel copper complex-based fluorescent probe [CuII(DQ468)Cl]+ that exhibits a significant fluorescence turn-on response towards nitroxyl with high selectivity over other biological reactive oxygen, nitrogen and sulfur species, including nitric oxide.

Azanone (HNO): generation, stabilization and detection

“… 195 In the recent years, many other Cu-based fluorescent probes for HNO detection have been developed, which have helped to understand the photophysical properties of these systems. 196,197 …”

“…195 In the recent years, many other Cubased fluorescent probes for HNO detection have been developed, which have helped to understand the photophysical properties of these systems. 196,197 Nitroxide compounds, which are organic compounds bearing an unpaired electron in an NO • motif, can also act as fluorogenic species, since they can act as quenchers when bound to a fluorophore. Nitroxides can be oxidized to the oxoammonium cations and are easily reduced by several compounds, including HNO, to yield the corresponding hydroxylamine.…”

Bioimaging agents based on redox-active transition metal complexes

“…Additionally, 73 could detect HNO effectively in the biological pH range, and the properties of water friendliness, low cytotoxicity and cell permeability, make 73 useful for the detection of HNO in living cells. 114 …”

Reaction-Based Luminescent Probes for Reactive Sulfur, Oxygen, and Nitrogen Species: Analytical Techniques and Recent Progress

“…Azanone (nitroxyl, HNO) has the most recent history of detection with reaction-based probes. The most common triggers are copper-based, − phosphine-based, − thiol-based, or nitroxide-based . Recent reviews have been written highlighting the advantages and disadvantages of these triggers, , and we will briefly summarize the salient points here.…”

“…The feasibility of using luminescent reaction-based probes for tracking azanone delivery via Angeli’s salt into living cells, − zebrafish, − , and mice ,, has been demonstrated in a number of recent studies. The endogenous production of azanone has been postulated, but in our view, this is still far from established.…”