碳点固定化荧光毛细传感器在线测定痕量铬(Ⅵ)  

On-line determination of trace-level Cr(Ⅵ)by carbon dots-immobilized fluorescent capillary sensor

作　　者：曹红艳 李永生[1] CAO Hongyan;LI Yongsheng(School of Chemical Engineering,Sichuan University,Chengdu 610065)

机构地区：[1]四川大学化学工程学院,成都610065

出　　处：《分析试验室》2022年第3期317-321,共5页Chinese Journal of Analysis Laboratory

摘　　要：将柠檬酸/乙二胺荧光碳点(CDs)通过与γ-氨丙基三乙氧基硅烷(KH550)的交联反应修饰在玻璃毛细管的内表面,开发了一种新的固定化碳点荧光毛细传感器(CDs-FCAS)。基于CDs与Cr(Ⅵ)之间的荧光猝灭反应,用于Cr(Ⅵ)含量的在线检测;并用PBS对反应后的传感器进行清洗,恢复传感器的荧光,实现了CDs-FCAS的重复利用。传感器荧光稳定性良好(RSD<3.5%)。对测定条件进行了优化:反应溶液pH 8.0、泵流量为1 mL/min。CDs-FCAS测定Cr(Ⅵ)的线性范围为0.1~2.0 mg/L,检出限为0.05 mg/L。该方法成功用于环境水中Cr(Ⅵ)的测定,回收率为95.1%~104.7%。A new carbon dots-immobilized fluorescent capillary sensor(CDs-FCAS)was developed by immobilizing CDs on the inner surface of glass capillary through cross-linking with KH550.CDs-FCAS was used for on-line detection of Cr(Ⅵ)based on fluorescence quenching reaction between CDs and Cr(Ⅵ).After reaction,the sensor was simply cleaned with PBS to recover its fluorescence.Therefore,the reuse of CDs-FCAS was realized.The fluorescence stability of the sensor was good(RSD<3.5%).At the same time,the determination conditions were optimized.The pH of reaction solution was 8.0 and pump flow rate was 1 mL/min.Under the optimized conditions,the linear range of CDs-FCAS for the determination of Cr(Ⅵ)was 0.1-2.0 mg/L with the detection limit of 0.05 mg/L.The method has been successfully applied to determine Cr(Ⅵ)in environmental water with recoveries of 95.1%-104.7%.

关 键 词：荧光碳点 固定化 荧光毛细传感器 在线测定 六价铬 

分 类 号：O657.31[理学—分析化学] X832[理学—化学]