Coumarin-based fluorescence turn-on probes for high selectivity peroxynitrite detection and imaging in living cells and γ-carrageenan-induced inflammatory tissue and mice

Peroxynitrite anion (ONOO-), a type of reactive nitrogen species (RNS), profoundly implicated in the physiological and pathological processes of a series of oxidative stress-related diseases. Thus, construction of reliable tools to track peroxynitrite (ONOO-) in biosystems is urgently desired. In this work, based-on D-pi-D-structure of coumarin derivative and 2-(4-nitrophenyl)-2-oxoacetamide (also served as the fluorescence quencher) as flourophore and response group, respectively, two fluorescence turn-on probes CMONOO1 and CMONOO2 were constructed for rapidly detection and imaging of ONOO- in living cells, and inflammatory tissues and mice. These two probes had fast response time for ONOO- (similar to 60 s), and exhibited highly selectivity and sensitivity detection performance for ONOO- over other ROS and RNS. Also they had excellent detection limits in the ranges of 0-1.0 mu M as low as 23.3 nM and 21.4 nM respectively. In addition, both probes have markedly biocompatibility, which could be beneficial to the imaging analysis of ONOO- in living biosystems. Therefore, CMONOO2 was selected as a representative for ONOO- imaging analysis in living cells, and inflammatory tissues and mice with satisfactory results, demonstrating these two robust probes have great potential to further elucidate ONOO--related diseases.

Automated summary

In this study, two fluorescence turn-on probes were constructed based on the D-pi-D structure, which were capable of rapidly detecting and imaging peroxynitrite (ONOO-) in living cells. These probes exhibited fast response time, highly selective and sensitive detection performance for ONOO-, and excellent detection limits. Moreover, they demonstrated remarkable biocompatibility, making them suitable for imaging analysis of ONOO- in living biosystems. Therefore, these probes have great potential in further elucidating ONOO--related diseases.