Abstract: " The pollution of Sb(III) in printing and dyeing wastewater poses a serious threat to ecology and human health, necessitating the development of efficient detection technologies. To address the limitations of conventional detection methods, such as inadequate sensitivity and complex operations, this study focuses on the advantages of fluorescence-based approaches to design novel fluorescent probes for enhancing the recognition performance of Sb(III). Among common fluorescent chromophores, pyrene, with its stable chemical structure and dimer luminescence properties, is frequently utilized in the detection of heavy metal ions. When modified with Sb(III) coordination groups containing N and O atoms, probes employing pyrene as the fluorescent chromophore can achieve a fluorescence enhancement response to Sb(III). What's more, introducing electron-donating substituents into the coordination groups is expected to increase the electron cloud density at the Sb(III) complexation sites, and improve the detection efficacy for Sb(III). Based on this, this paper designs and synthesizes a fluorescent probe, Py-ph-OCH3, using pyrene as the fluorescent chromophore and 2-amino-4-methoxyphenol as the functional group. The p-π conjugation effect between the methoxy group and the benzene ring in the probe's functional group is leveraged to enhance the electron cloud density of the N and O atoms at the Sb(III) complexation sites, and augment the fluorescence detection performance of Py-ph-OCH3 for Sb(III). Firstly, Py-ph-OCH3 was successfully synthesized and its chemical structure was determined. Subsequently, its stability under different environmental conditions was tested. The results showed that Py-ph-OCH3 exhibited good thermal stability, with a thermal decomposition temperature of 280 °C and a melting temperature of 188 °C. Additionally, Py-ph-OCH3 demonstrated excellent solvent stability, as solutions prepared in organic solvents with varying polarities showed similar ultraviolet absorption and fluorescence spectra. When the pH was in the range of 5.5 to 9.0 and the temperature was between 25 °C and 75 °C, the fluorescence intensity of the Py-ph-OCH3 solution remained relatively unchanged, indicating that the probe possesses outstanding pH and temperature stability. Next, the fluorescent detection effect of Py-ph-OCH3 on Sb(III) was investigated in a DMSO/H2O mixed system. The results showed that Py-ph-OCH3 exhibited the optimal fluorescence detection effect for Sb(III) when the volume fraction of water in the system was 80% and the probe concentration was 100 mol/L. Under these conditions, as the Sb(III) concentration increased from 0 to 0.1 mmol/L, the fluorescence enhancement factor of Py-ph-OCH3 on Sb(III) increased with the Sb(III) concentration. The relationship between them followed the equation Y = 157.02682X + 0.17031, with an R² value of 0.99379. The detection limit was determined to be 1.185 mol/L, indicating that Py-ph-OCH3 possesses extremely high sensitivity for the detection of Sb(III). Furthermore, this detection process was not interfered by other common metal ions, showing good specificity and selectivity. In conclusion, this study successfully synthesized the fluorescent probe Py-ph-OCH3 using pyrene as the fluorescent chromophore and 2-amino-4-methoxyphenol as the functional group. The probe exhibits good stability and can achieve efficient, sensitive and specific detection of Sb(III) in the DMSO/H2O mixed system. The research may provide valuable insights for the detection of Sb(III) in industrial wastewater in the future."

Key words: detection of Sb(III), pyrene, dimer fluorescence, electron-donating effect, complexation, fluorescence enhancement response

摘要： 为了简便高效检测重金属离子Sb(III)，以芘为生色团、以2-氨基-4-甲氧基苯酚为功能基团制备了荧光探针Py-ph-OCH3，验证了Py-ph-OCH3的结构，测试了Py-ph-OCH3的稳定性，探究了Py-ph-OCH3在二甲基亚砜（DMSO）/H2O体系中的发光特性和Sb(III)荧光检测效果。结果表明：Py-ph-OCH3在不同有机溶剂、温度为25~75 ℃、pH值为5.5~9.0的体系中均保持良好的发光稳定性。在DMSO/H2O体系中，Py-ph-OCH3分子呈现出二聚体发光特性。当水的体积分数为80%、Py-ph-OCH3浓度为100 mol/L时，由于Py-ph-OCH3功能基团中N、O原子与Sb(III)的络合作用以及甲氧基的供电子效应，Py-ph-OCH3对Sb(III)表现出优异的荧光检测效果，荧光增强倍数最高可达15.29，检测浓度下限可以低至1.185 mol/L，且整个过程不受其他常见金属离子的干扰。研究结果可对印染废液中Sb(III)的精确检测提供参考。

关键词: Sb(III)检测, 芘, 二聚体荧光, 供电子效应, 络合作用, 荧光增强响应