Chen Jiaqian, Meng Haimei, Fang Zhijia, Lukman Iddrisu, Gao Jialong, Liao Jianmeng, Deng Qi, Sun Lijun, Gooneratne Ravi
College of Food Science and Technology, Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Guangdong Provincial Engineering Technology, Research Center of Marine Food, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Continuing Education, Guangdong Ocean University, Zhanjiang, 524088, China.
Zhanjiang Institute for Food and Drug Control, Zhanjiang, 524022, China.
Heliyon. 2024 Feb 27;10(5):e26980. doi: 10.1016/j.heliyon.2024.e26980. eCollection 2024 Mar 15.
In this study, we have developed a novel fluorescent "OFF-ON" quantum dots (QDs) sensor based on CdTe/CdS/SiO cores. Ammonium pyrrolidine dithiocarbamate (APDC), ethylenediamine tetraacetic acid (EDTA), and 1,10-phenanthroline (Phen) served as potential chemical etchants. Among these three etchants, APDC exhibited the most pronounced quenching effect (94.06%). The APDC-etched CdTe/CdS/SiO QDs demonstrated excellent optical properties: the fluorescence of the APDC-etched CdTe/CdS/SiO QDs system (excitation wavelength: 365 nm and emission wavelength: 622 nm) was significantly and selectively restored upon the addition of cadmium ions (Cd) (89.22%), compared to 15 other metal ions. The linear response of the APDC-etched CdTe/CdS/SiO QDs was observed within the cadmium ion (Cd) concentration ranges of 0-20 μmol L and 20-160 μmol L under optimized conditions (APDC: 300 μmol L, pH: 7.0, reaction time: 10 min). The detection limit (LOD) of the APDC-etched CdTe/CdS/SiO QDs for Cd was 0.3451 μmol L in the range of 0-20 μmol L. The LOD achieved by the QDs in this study surpasses that of the majority of previously reported nanomaterials. The feasibility of using APDC-etched CdTe/CdS/SiO QDs for Cd detection in seawater, freshwater, and milk samples was verified, with average recoveries of 95.27%-110.68%, 92%-106.47%, and 90.73%-111.60%, respectively, demonstrating satisfactory analytical precision (RSD ≤ 8.26).
在本研究中，我们基于碲化镉/硫化镉/二氧化硅核开发了一种新型荧光“关-开”量子点（QDs）传感器。吡咯烷二硫代氨基甲酸铵（APDC）、乙二胺四乙酸（EDTA）和1,10-菲啰啉（Phen）用作潜在的化学蚀刻剂。在这三种蚀刻剂中，APDC表现出最显著的猝灭效果（94.06%）。经APDC蚀刻的碲化镉/硫化镉/二氧化硅量子点表现出优异的光学性质：与其他15种金属离子相比，在添加镉离子（Cd）后，经APDC蚀刻的碲化镉/硫化镉/二氧化硅量子点体系（激发波长：365nm，发射波长：622nm）的荧光显著且选择性地恢复（89.22%）。在优化条件下（APDC：300μmol/L，pH：7.0，反应时间：10分钟），在镉离子（Cd）浓度范围为0 - 20μmol/L和20 - 160μmol/L内观察到经APDC蚀刻的碲化镉/硫化镉/二氧化硅量子点的线性响应。在0 - 20μmol/L范围内，经APDC蚀刻的碲化镉/硫化镉/二氧化硅量子点对镉的检测限（LOD）为0.3451μmol/L。本研究中量子点实现的检测限超过了大多数先前报道的纳米材料。验证了使用经APDC蚀刻的碲化镉/硫化镉/二氧化硅量子点检测海水、淡水和牛奶样品中镉的可行性，平均回收率分别为95.27% - 110.68%、92% - 106.47%和90.73% - 111.60%，显示出令人满意的分析精密度（RSD≤8.26）。
