Hg^2+@CDs的荧光传感体系检测水质中的I-  

Detection of I^-in Water by the Hg^2+@CDs Fluorescent Sensor

作　　者：叶嘉文 常晶晶 耿乙迦 崔媛 徐抒平[2] 徐蔚青[2] 陈奇丹 YE Jia-wen;CHANG Jing-jing;GENG Yi-jia;CUI Yuan;XU Shu-ping;XU Wei-qing;CHEN Qi-dan(School of Chemical and Environmental Engineering,Changchun University of Science and Technology,Changchun 130022,China;State Key Laboratory of Supramolecular Structure and Materials,Institute of Theoretical Chemistry,Jilin University,Changchun130012,China;School of Chemical Industry and New Energy Materials,Zhuhai College,Jilin University,Zhuhai 519041,China)

机构地区：[1]长春理工大学化学与环境工程学院,吉林长春13002 [2]吉林大学超分子结构与材料国家重点实验室,吉林长春130012 [3]吉林大学珠海学院化工与新能源材料学院,广东珠海519041

出　　处：《光谱学与光谱分析》2020年第11期3489-3493,共5页Spectroscopy and Spectral Analysis

基　　金：广东省普通高校重点领域专项基金项目(2020ZDZX2036);广东省基础与应用基础研究基金项目(2019A1515010596);国家自然科学基金项目(21573087,21573092,21873039)资助。

摘　　要：在人体内部环境中,碘是合成甲状腺激素的关键原料之一,而甲状腺激素主要功能是促进人体生长发育以及调节新陈代谢,因此碘对人体内部环境正常运转起到至关重要的作用。碘在人体内主要以碘化氨基酸的形式存在于甲状腺中,对其常用的检测手段有很多种。而这些方法虽然具有较高精度以及灵敏度高,但检测过程较为复杂且检测周期较长。因此,发展一种成本较低、操作简单、快速准确的I-检测方法具有应用意义。研究设计一种简便且快速精准的I-检测方法,利用荧光"Off-On"传感体系对溶液中I-进行定量检测。以柠檬酸为碳源、乙二胺为氮源,通过水热法一步合成水溶性较好且具有良好荧光性质的碳点(CDs)。利用荧光光谱仪以及紫外-可见光光谱仪对该CDs的光学性能进行表征。通过分析CDs的光谱可知该CDs的激发波长为345 nm,发射波长为470 nm。另外,通过傅里叶-红外光谱仪以及高分辨紫外光电子能谱对该CDs表面的官能团以及元素进行分析检测。通过荧光光谱进行检测,可以发现当CDs溶液中存在Hg^2+时, CDs的荧光发生猝灭现象。其原因是CDs与Hg^2+的d轨道间非辐射电子转移或Hg^2+与CDs表面的氨结合形成非荧光复合物,导致CDs的荧光强度下降。通过将最佳浓度的Hg^2+与CDs溶液进行混合,来制备Hg^2+@CDs的荧光传感体系溶液。分析Hg^2+@CDs的荧光传感体系溶液的荧光光谱图可以发现,当Hg^2+@CDs的荧光传感体系溶液中存在I-时,体系荧光强度随着I-浓度的上升而逐渐增强。该原因可以归根于I-与Hg^2+之间存在较强的相互作用可将Hg^2+从CDs表面脱附,使CDs的荧光重新恢复,从而实现I-的荧光"Off-On"检测。利用该方法来检测溶液中的I-,其检测范围在5.0~75μmol·L^-1,而检测限为0.25μmol·L^-1。实验最后还利用荧光光谱仪对Hg^2+@CDs的荧光传感体系的选择性以及抗干扰能力进行分析,结果�In the human body,iodine is the key raw material for thyroid hormone.Moreover,thyroid hormone had a critical role in human growth and development and regulated metabolism,so iodine was played a vital role in the normal operation of the human body.The iodine was mainly in the form of iodinated amino acids presented in the thyroid gland.Furthermore,many methods were used to detect I^-with high precision and accuracy.However,most of the approaches lie in complicated operations and high detection cost.Therefore,it is of great significance to develop a method for detecting I-with low cost,fast,accuracy and simple operation.In this study,a simple and convenient fluorescence“Off-On”detection method was used for I-testing in solution.The carbon nanodots(CDs)were synthesized by a simple hydrothermal method,which citric acid and ethane diamine were used as the carbon source and the nitrogen source.The optical properties of the CDs were characterized by a fluorescence spectrometer and an ultraviolet-visible spectrometer,which emitted bright blue light at an excitation wavelength of 350 nm.Additionally,the groups on the surface of the CDs were characterized by the Fourier-infrared spectroscopy and high resolution ultraviolet photoelectron spectroscopy.The fluorescence of the prepared CDs can be pre-quenched by Hg^2+.And the fluorescence quenching may be due to the non-radiative electron-transfer from the excited states to the d orbital of Hg 2+.Another possible explanation is attributed to the Hg^2+ions combine with a large amount of nitrogen on the surface of the CDs to form a non-fluorescent complex,which leads to fluorescence quenching of CDs.The optimal concentration condition of Hg^2+was selected by analyzing the fluorescence spectrum of CDs solution with different concentration Hg 2+.Once they meet I^-in the solution,Hg^2+on the surface of the CDs will be released due to the strong interaction between Hg^2+and I^-,and the fluorescence of CDs can be restored.Thus,I^-in the solution can be detectable by this fluoresc

关 键 词：碳点(CDs) 相互作用力 I- “关-开” 荧光检测 竞争 

分 类 号：O661.1[理学—分析化学]