Scholarlink

<p>A novel Schiff base compound, 3-hydroxy-(2-hydroxy-3,5-dichlorobenzylidene)-2-naphthohydrazide (<b>HDN</b>), was successfully synthesized through the condensation of 3-hydroxy-2-naphthoylhydrazide with 3,5-dichlorosalicylaldehyde. The molecular structure was comprehensively characterized using NMR, HR-MS, and FT-IR analysis. Spectroscopic investigations revealed that <b>HDN</b> demonstrates a selective “turn-off” fluorescent response towards Co<sup>2+</sup> ions in a PBS: DMF (4:6, v/v) medium with minimal interference from competing metal ions. Mechanistic investigations, including Job’s plot analysis and ¹H NMR titration, confirmed a 1:1 binding stoichiometry between <b>HDN</b> and Co<sup>2+</sup>. Density functional theory (DFT) calculations suggested that fluorescence quenching is due to enhanced self-absorption effects upon complex formation. A linear calibration curve was established between fluorescence intensity and Co<sup>2+</sup> concentration within the range of 0.1–10 µM, with a detection limit of 5.57 × 10<sup>−8</sup> mol/L. Additionally, <b>HDN</b> exhibited significant viscosity-sensitive emission behavior during chitosan cross-linking processes. These findings establish <b>HDN</b> as a dual-functional probe for both environmental Co<sup>2+</sup> monitoring and real-time viscosity detection in polymer matrix systems.</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 New Fluorescence Probe Based on Self-absorption for Detection of Co2+ and Viscosity

  • 期刊论文

  • 发表日期：

    2025年10月14日

查看全文
  • Huizhen Wang,
  • Dingxin Qiu,
  • Yan Tang,
  • Pengbo Wang,
  • Pei Wu,
  • Guanjun Chang

摘要

A novel Schiff base compound, 3-hydroxy-(2-hydroxy-3,5-dichlorobenzylidene)-2-naphthohydrazide (HDN), was successfully synthesized through the condensation of 3-hydroxy-2-naphthoylhydrazide with 3,5-dichlorosalicylaldehyde. The molecular structure was comprehensively characterized using NMR, HR-MS, and FT-IR analysis. Spectroscopic investigations revealed that HDN demonstrates a selective “turn-off” fluorescent response towards Co2+ ions in a PBS: DMF (4:6, v/v) medium with minimal interference from competing metal ions. Mechanistic investigations, including Job’s plot analysis and ¹H NMR titration, confirmed a 1:1 binding stoichiometry between HDN and Co2+. Density functional theory (DFT) calculations suggested that fluorescence quenching is due to enhanced self-absorption effects upon complex formation. A linear calibration curve was established between fluorescence intensity and Co2+ concentration within the range of 0.1–10 µM, with a detection limit of 5.57 × 10−8 mol/L. Additionally, HDN exhibited significant viscosity-sensitive emission behavior during chitosan cross-linking processes. These findings establish HDN as a dual-functional probe for both environmental Co2+ monitoring and real-time viscosity detection in polymer matrix systems.