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Updated: Feb 6, 2026

Application of Membrane and Cell Wall Selective Fluorescent Dyes for Live-Cell Imaging of Filamentous Fungi
Published on: November 28, 2019
A new selective fluorescence probe with a quinoxalinone structure (QP-1) for cysteine and its application in
Bing Yang1, Jing Xu1, Zeng-Hui Yuan1
1State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210023, China.
Abstract:
A new selective probe with a quinoxalinone structure, QP-1, has been developed for detection of Cys from biothiols. QP-1 features superb selectivity to Cys and a wide pH range. QP-1 has selectivity to Cys over Hcy, GSH, other amino acids and ions. HRMS spectra confirmed that the detection process was a conjugate addition-addition-elimination reaction. Moreover, QP-1 has been successfully applied in the imaging of Cys in living cells. Finally, QP-1 has been used to detect Cys in rat urine samples.
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