基于氮掺杂石墨烯量子点和二硫苏糖醇的比率型检测铜离子的荧光探针  

A ratiometric fluorescent probe based on nitrogen-doped graphene quantum dots and dithiothreitol for copper ions determination

作　　者：申婧翔[1] 白建良 马珑珑 秦立波 苏静[1] SHEN Jingxiang;BAI Jianliang;MA Longlong;QIN Libo;SU Jing(Department of Chemistry,Changzhi University,Changzhi 046011,China)

机构地区：[1]长治学院化学系,长治046011

出　　处：《分析试验室》2025年第4期517-523,共7页Chinese Journal of Analysis Laboratory

基　　金：山西省高等学校科技创新项目(2023L330)资助。

摘　　要：以柠檬酸和尿素为前驱体,通过一步水热法合成了发射蓝光(445 nm)的氮掺杂石墨烯量子点(N-GQDs);通过与含有巯基(-SH)的二硫苏糖醇(DTT)直接混合,构建了比率型检测铜离子(Cu^(2+))的复合荧光探针体系N-GQDs/DTT。当向该复合探针体系中加入目标分析物Cu^(2+)时,一方面,基于静态猝灭效应,N-GQDs于445 nm处的荧光强度逐渐降低;另一方面,由于-SH与Cu^(2+)的强键合作用,DTT与Cu^(2+)立即发生原位反应生成发射红光(666 nm)的铜纳米颗粒(DTT-Cu NPs),且666 nm处的荧光强度逐渐增加。666 nm及445 nm处荧光强度的比值(F_(666)/F_(445))与加入的Cu^(2+)浓度分别在1~20μmol/L和20~360μmol/L范围内呈线性,线性拟合方程分别为y=0.00558x+0.00992(R^(2)=0.998)和y=0.00262x+0.0855(R^(2)=0.996)。据此实现了Cu^(2+)的比率型检测,检出限为0.05μmol/L。Herein,blue emissive(445 nm)nitrogen-doped graphene quantum dots(N-GQDs)were synthesized via one-step hydrothermal method using citric acid and urea as raw materials.The composite fluorescent probe system N-GQDs/DTT was constructed by direct mixing N-GQDs with dithiothreitol(DTT)containing sulfhydryl(-SH)to construct a ratiometric fluorescent probe for detecting copper ions(Cu^(2+)).With the addition of target Cu^(2+)in the probe system,the fluorescence intensity at 445 nm decreased gradually because of static quenching effect;on the other hand,the fluorescence intensity at 666 nm increased gradually due to the in-situ formation of red emitting copper nanoparticles(DTT-Cu NPs),which was attributed to the strong bond affinity between?SH and Cu^(2+).The ratio of fluorescence intensity at 666 nm and 445 nm(F_(666)/F_(445))showed linear relationships with Cu^(2+)concentration in the ranges of 1?20μmol/L and 20?360μmol/L,and the linear equations were expressed as y=0.00558x+0.00992(R^(2)=0.998)and y=0.00262x+0.0855(R^(2)=0.996),respectively.The limit of detection(LOD)for ratiometric detection of Cu^(2+)was 0.05μmol/L.

关 键 词：氮掺杂石墨烯量子点 二硫苏糖醇 铜纳米颗粒 铜离子 比率型荧光探针 

分 类 号：O657.3[理学—分析化学] TS207.3[理学—化学]