Near-infrared Rhodols-based fluorescent probe with large Stokes shift for tracking of H2S in food spoilage and living cells

• Published in: Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy Molecular and biomolecular spectroscopy, 2024-07, Vol.315, p.124250, Article 124250
• Main Authors: Yu, Qiangmin, Mao, Yanyun, Bai, Tianwen, Ye, Tianqing, Peng, Zhengyuan, Chen, Kan, Guo, Longhua, Li, Lei, Wang, Jianbo
• Format: Article
• Language: English
• Subjects: Food sample; H2S; Large Stokes shift; NIR probe
• ISSN: 1386-1425
• DOI: 10.1016/j.saa.2024.124250

[Display omitted] •A new near-infrared fluorescent probe HR for specially responses toward H2S was synthesized.•Probe displays a colormetric and NIR fluorescent response toward H2S with large Stokes shift, high selectivity and sensitivity.•Probe can be applied for sensing detection of H2S in food spoilage and living cells. Hydrogen sulfide (H2S), as a biomarker signaling gas, is not only susceptible to food spoilage, but also plays a key function in many biological processes. In this work, an activated near infrared (NIR) H2S fluorescent probe was designed and synthesized with quinoline-conjugated Rhodols dye as fluorophore skeleton and a dinitrophenyl group as the responsive moiety. Due to the quenching effect of dinitrophenyl group and the closed-loop structure of Rhodols fluorophore, probe itself has a very weak absorption and fluorescence background signal. After the H2S-induced thiolysis reaction, the probe exhibits a remarkable colormetric change and NIR fluorescent enhancement response at 716 nm with large Stokes shift (116 nm), and possesses high sensing selectivity and sensitivity with a low detection limits of 330 nM. The response mechanism is systematically characterized by 1H NMR, MS and DFT calculations. The colorimetric change allows the probe to be used as a test strips to detect H2S in food spoilage, while NIR fluorescent response helps the probe monitor intracellular H2S.