氮掺杂碳量子点的合成及作为荧光探针对Hg^(2+)的检测  

Synthesis of Nitrogen-Doped Carbon Quantum Dots and Its Application as Fluorescent Sensor for Hg^(2+)

作　　者：李玲玲[1] 倪刚[1] 王嘉楠[1] 李静[1] 李微[1] 

机构地区：[1]宁夏大学化学化工学院,宁夏银川750021

出　　处：《光谱学与光谱分析》2016年第9期2846-2851,共6页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(21567021;21365016);宁夏高校科学研究基金项目(2012);宁夏大学提升综合实力建设项目(8016-18);宁夏大学2015年度研究生创新项目(GIP2015012)资助

摘　　要：与传统量子点相比,碳量子点作为一种新型的荧光碳纳米材料,由于其良好的生物相容性、易于表面功能化、低毒性等优点受到了广泛关注。采用柠檬酸为碳源,氨水为氮源,热解法制备出水溶性好的氮掺杂碳量子点(NCDs)。透射电镜(TEM)观察NCDs的粒径在3nm左右;X射线光电子能谱(XPS)和傅里叶红外光谱(FIIR)证明NCDs的表面被羧基、氨基、羟基、羰基等官能团功能化,说明NCDs有很好的水溶性。研究还发现Hg^(2+)对NCDs的荧光有良好的猝灭作用,可作为荧光探针检测水中Hg^(2+)含量。在PBS缓冲液中(0.1mol·L^(-1) pH 7.0),NCDs的荧光猝灭率(F/F0)与汞离子浓度在0.001~0.1μmol·L^(-1)之间存在良好的线性关系,检出限为2.1nmol·L^(-1)。该方法灵敏度高、选择性好、方法简便,可应用于Hg^(2+)快速、灵敏的检测。Compared with traditional quantum dots,carbon quantum dots （CQDs）have aroused tremendous research interest among scientists as new fluorescent carbon nanomaterials due to their unique properties （easy surface functionalization,good bio-compatibility,and low toxicity）.The nitrogen-doped carbon quantum dots （NCDs）was synthesized with one-step hydrothermal treatment with citric acid as carbon source,and ammonia as nitrogen source.The obtained NCDs exhibited excellent water-solu-bility and high stability.High-resolution Transmission electron microscopy （HRTEM）image showed that the diameter of parti-cles was about 3nm.Fourier transform infrared （FIIR）and X-ray photoelectron spectroscopy （XPS）spectra analysis demonstra-ted that the NCDs are functionalized with hydroxyl,amino,carbonyl,and carboxylic acid groups,which indicated NCDs has better water-solubility.It was further demonstrated that such NCDs can serve as effective fluorescent sensing platform for Hg2＋ ions detection with sensitivity and selectivity.In a PBS butter solution （0.1 mol·L-1 pH 7.0）,the fluorescence quenching ratio （F/F0 ）indicated linear responses with Hg2＋ concentration ranging from 0.001 to 0.1 μmol·L-1 ,with the detection limit of 2.1 nmol·L-1 .The fluorescence technique was superior in terms of sensitivity,selectivity and simplicity.It was successfully applied to determination of Hg2＋ in samples.

关 键 词：碳量子点 氮掺杂 荧光探针 汞离子 

分 类 号：O657.3[理学—分析化学]