An “off-on” fluorescent nanosensor for the detection of cadmium ions based on APDC-etched CdTe/CdS/SiO2 quantum dots
Jiaqian Chen,
Haimei Meng,
Zhijia Fang,
Iddrisu Lukman,
Jialong Gao,
Jianmeng Liao,
Qi Deng,
Lijun Sun,
Ravi Gooneratne
Affiliations
Jiaqian Chen
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
Haimei Meng
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
Zhijia Fang
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; Corresponding author.
Iddrisu Lukman
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
Jialong Gao
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
Jianmeng Liao
Zhanjiang Institute for Food and Drug Control, Zhanjiang, 524022, China
Qi Deng
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
Lijun Sun
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
Ravi Gooneratne
Department of Wine, Food and Molecular Biosciences, Lincoln University, Lincoln, Canterbury, 7647, New Zealand
In this study, we have developed a novel fluorescent ''OFF-ON'' quantum dots (QDs) sensor based on CdTe/CdS/SiO2 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/SiO2 QDs demonstrated excellent optical properties: the fluorescence of the APDC-etched CdTe/CdS/SiO2 QDs system (excitation wavelength: 365 nm and emission wavelength: 622 nm) was significantly and selectively restored upon the addition of cadmium ions (Cd2+) (89.22%), compared to 15 other metal ions. The linear response of the APDC-etched CdTe/CdS/SiO2 QDs was observed within the cadmium ion (Cd2+) concentration ranges of 0–20 μmol L−1 and 20–160 μmol L−1 under optimized conditions (APDC: 300 μmol L−1, pH: 7.0, reaction time: 10 min). The detection limit (LOD) of the APDC-etched CdTe/CdS/SiO2 QDs for Cd2+ was 0.3451 μmol L−1 in the range of 0–20 μmol L−1. 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/SiO2 QDs for Cd2+ 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).
