An ultra-sensitive electrochemical aptasensor for simultaneous quantitative detection of Pb2+ and Cd2+ in fruit and vegetable. (15th July 2022)

• Record Type: Journal Article
• Authors: Yuan, Min; Qian, Shiquan; Cao, Hui; Yu, Jinsong; Ye, Tai; Wu, Xiuxiu; Chen, Limin; Xu, Fei
• Is Part Of: Food chemistry. Volume 382(2022)
• Publication Date: 2022-07-15
• Subjects: Cadmium ion -- Lead ion -- Electrochemical aptasensor -- Aptamer -- Heavy metal ions detection -- Fruit and vegetable; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.132173
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: An ultrasensitive electrochemical aptasensor was developed to detect Pb 2+ and Cd 2+ simultaneously. The proposed sensor is used to selectively and sensitively determine trace Pb 2+ and Cd 2+ in fruit and vegetable. The aptasensor displayed low detection limit of 16.44 pmol/L for Pb 2+ and 89.31 pmol/L for Cd 2+ . Abstract: An electrochemical aptasensor based on aptamer was designed for the first time to simultaneously detect Cd 2+ and Pb 2+ in fruit and vegetable. The double-stranded DNA including aptamers were immobilized on the electrode via Au-S bond. Due to the specific binding of aptamer and metal ions, the aptamers labelled with methylene blue or ferrocene were competed off the gold electrode, and the electrochemical signal was decreased. Under the optimal conditions, the electrochemical aptasensor showed linear response to Cd 2+ and Pb 2+ in the range of 0.1 to 1000 nmol/L, and the detection limits of Cd 2+ and Pb 2+ achieved 89.31 and 16.44 pmol/L (3σ), respectively. Excellent stability and reproducibility were exhibited with RSD 2.27% (Cd 2+ ) and 3.61% (Pb 2+ ). The digested fruit and vegetable were also tested, and the recoveries were in the range of 90.06% to 97.24%. Thus, this strategy held great potential in monitoring cadmium and lead pollution.