Scholarlink

<p>The accurate quantification of tea polyphenols (TP) is crucial for health and safety monitoring. While iron doping can enhance sensing performance, conventional iron-doped fluorescent probes are constrained by short emission wavelengths (below 600&#xa0;nm) and heterogeneous metal distribution. To overcome these limitations, we developed a novel synthesis strategy for red-emissive iron-doped carbon dots (Fe-CDs), employing EDTA-Fe coordination complexes as controlled dopant carriers and Azure A-derived carbon frameworks as tunable emission matrices. The resulting Fe-CDs enable sequential detection of TP and Mn(VII) via a smart “off–on” fluorescence switching mechanism. In this system, TP quenches the fluorescence of Fe-CDs through ground-state complex formation, affording two linear response ranges (0.05–2.5&#xa0;µM and 2.5–9&#xa0;µM) with a detection limit of 28.7&#xa0;nM. The subsequent introduction of Mn(VII) restores the fluorescence signal due to the stronger affinity between TP and Mn(VII), allowing Mn(VII) quantification across two linear intervals (2–42.5&#xa0;µM and 47.5–130&#xa0;µM) with a limit of detection of 191.9&#xa0;nM. Practical applicability was confirmed through spike-recovery tests, yielding recoveries of 98.81–107.0% for TP in tea samples and 101.7–108.1% for Mn(VII) in environmental water. This work establishes an atomic-level iron-doping approach that allows precise modulation of the electronic structure and surface functionality of carbon dots, thereby providing a robust dual-analyte fluorescence platform for food quality control and environmental surveillance.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

A Switchable Fluorescent Nanosensor Based on In Situ Iron-Doped Carbon Dots for Sequential Detection of Tea Polyphenols and Mn(VII)

  • 期刊论文

  • 发表日期：

    2026年7月28日

查看全文
  • Xuewen Miao,
  • Chao Liu,
  • Xiaona Liu,
  • Yifang Gao,
  • Junmei Guo,
  • Tianwei Qian,
  • Yuan Jiao

摘要

The accurate quantification of tea polyphenols (TP) is crucial for health and safety monitoring. While iron doping can enhance sensing performance, conventional iron-doped fluorescent probes are constrained by short emission wavelengths (below 600 nm) and heterogeneous metal distribution. To overcome these limitations, we developed a novel synthesis strategy for red-emissive iron-doped carbon dots (Fe-CDs), employing EDTA-Fe coordination complexes as controlled dopant carriers and Azure A-derived carbon frameworks as tunable emission matrices. The resulting Fe-CDs enable sequential detection of TP and Mn(VII) via a smart “off–on” fluorescence switching mechanism. In this system, TP quenches the fluorescence of Fe-CDs through ground-state complex formation, affording two linear response ranges (0.05–2.5 µM and 2.5–9 µM) with a detection limit of 28.7 nM. The subsequent introduction of Mn(VII) restores the fluorescence signal due to the stronger affinity between TP and Mn(VII), allowing Mn(VII) quantification across two linear intervals (2–42.5 µM and 47.5–130 µM) with a limit of detection of 191.9 nM. Practical applicability was confirmed through spike-recovery tests, yielding recoveries of 98.81–107.0% for TP in tea samples and 101.7–108.1% for Mn(VII) in environmental water. This work establishes an atomic-level iron-doping approach that allows precise modulation of the electronic structure and surface functionality of carbon dots, thereby providing a robust dual-analyte fluorescence platform for food quality control and environmental surveillance.