可视化辅助双碳点比率荧光检测水中银离子  

Detection of Silver Ions in Water by Dual Carbon Dots Based on Vi⁃sualization-assisted Ratiometric Fluorescent

作　　者：韩雍[1] 马艳鑫 汪慧[1] 王雅[2] HAN Yong;MA Yan-xin;WANG Hui;WANG Ya(College of Agriculture and Forestry,Longdong University,Qingyang 745000,China;School of Life Sciences and Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]陇东学院农林科技学院,甘肃庆阳745000 [2]兰州理工大学生命科学与工程学院,甘肃兰州730050

出　　处：《分析测试学报》2023年第12期1623-1630,共8页Journal of Instrumental Analysis

基　　金：国家自然科学基金(32060571);甘肃省科技厅项目(21JR7RM186,22JR5RM204,23CXGM0001);中国科学院“西部之光”人才基金(2020XBZGXBQNXZ-A);甘肃省陇原创新人才(团队)(2022LQTD36)。

摘　　要：该文以柠檬酸、L-半胱氨酸(L-Cys)和邻苯二胺(OPD)为前体通过一步水热法分别合成了蓝光碳点(B-CDs)与黄光碳点(Y-CDs),将两者杂化形成双碳点(d-CDs),并基于该d-CDs构建了快速检测环境水样中Ag^(+)的可视化比率荧光传感器。采用透射电子显微镜、红外光谱、X射线光电子能谱、紫外吸收光谱、荧光光谱对d-CDs的结构和光学性能进行表征。考察了pH值、反应温度、孵育时间等因素对传感器检测效果的影响并进行了优化。d-CDs呈球形,分散性好且分布均匀,平均粒径为2.14 nm,含有巯基和芳香环结构,并存在大量的羟基和羧基基团。Ag^(+)能与d-CDs表面的官能团发生官能团配位形成d-CDs/Ag^(+)复合物,并可通过光致能量转移(PET)猝灭d-CDs的蓝色荧光。另外Ag^(+)能够与d-CDs含有的巯基结合产生絮凝物。随着蓝色荧光的减弱,体系呈现出黄色荧光增强的现象。该传感器在Ag^(+)浓度0~40μmol/L范围内呈良好的线性响应,相关系数(r^(2))为0.9967,检出限(LOD)为1.26μmol/L,加标回收率为98.2%~105%,相对标准偏差(RSD)为0.49%~3.8%。该方法具有快速、简便、灵敏度和可靠性高的优势,并可实现环境水样中Ag^(+)的可视化半定量检测。In this work,blue carbon dots(B-CDs)and yellow carbon dots(Y-CDs)were synthe⁃sized through a hydrothermal method using citric acid,L-cysteine(L-Cys)and o-phenylenediamine(OPD)as precursors respectively,then hybridized dual carbon dots to form a visual ratiometric fluo⁃rescent sensor(d-CDs)for the rapid detection of Ag^(+)in environmental water samples.The structural and optical properties of d-CDs were characterized using transmission electron microscope(TEM),Fourier transform infrared(FTIR),X-ray photoelectron spectroscopy(XPS),X-ray diffraction(XRD),ultraviolet absorption spectroscopy and fluorescence spectroscopy.The effects of pH,reac⁃tion temperature and incubation time of the sensor were investigated and optimized.The d-CDs are spherical with an average particle size of 2.14 nm,which were well dispersed and uniformly distrib⁃uted in the solution.The d-CDs contain mercapto and aromatic ring structures and a large number of hydroxyl and carboxyl groups,which can induce d-CDs/Ag^(+)complexes in the presence of Ag^(+)and quenched the blue fluorescence of d-CDs by photoinduced energy transfer(PET).As the blue fluores⁃cence decreases,yellow fluorescence significant increases in the ratiometric fluorescent system.The sensor showed good linear response in the range of Ag^(+)concentration 0-40μmol/L with the r^(2) of 0.9967 and the limit of detection(LOD)of 1.26μmol/L.The spiked recoveries were 98.2%-105%with the rel⁃ative standard deviations of 0.49%-3.8%in practical test.The method is rapid,simple,sensitive and reliable,and can realize the visual semi-quantitative detection of Ag^(+)in environmental water samples.

关 键 词：碳点 比率荧光 可视化检测 银离子 水 

分 类 号：O657.3[理学—分析化学] O661.1[理学—化学]