High sensitivity electrochemical detection of ultra-trace imidacloprid in fruits and vegetables using a Fe-rich FeCoNi-MOF. (15th May 2023)

• Record Type: Journal Article
• Authors: Shu, Hui; Lai, Tingrun; Yang, Zhichao; Xiao, Xuechun; Chen, Xiumin; Wang, Yude
• Is Part Of: Food chemistry. Volume 408(2023)
• Publication Date: 2023-05-15
• Subjects: Ultra-trace imidacloprid -- Electrochemical sensor -- Fe-rich FeCoNi-MOF -- Catalytic activity -- Detection mechanism; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.135221
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Fe-rich FeCoNi-MOF was in-situ grown on nickel foam working electrode. The electrochemical sensor was constructed using Fe-rich FeCoNi-MOF nickel foam. The electrochemical sensor has high sensitivity to ultra-trace imidacloprid. The detection mechanism was revealed by valence states and theoretical calculations. The electrochemical sensor was applied to detect imidacloprid in vegetables and fruits. Abstract: High sensitivity and ultra-trace detection of imidacloprid are important and challenging in the field of food. In this study, we prepared a Fe-rich FeCoNi-MOF in-situ modified nickel foam working electrode by one-step hydrothermal method, and achieved a highly sensitive detection of the imidacloprid. The characterization techniques confirmed that Fe-rich FeCoNi-MOF had excellent crystallinity, tighter structure, and exposed rich active sites. The detection results showed that Fe-rich FeCoNi-MOF electrochemical sensor had a minimum detection limit of 0.04 pmol/L (100 times lower than that of the bioelectrochemical sensors), a wide response range (1 pmol/L–120 μmol/L), and high sensitivity (124 μA pmol/L -1 cm −2 ). These advantages of the electrochemical sensor were revealed theoretically by the valence change of active metal and the first principle calculation. Lastly, the Fe-rich FeCoNi-MOF electrochemical sensor was applied to detect imidacloprid in apple, fresh tea leaves, tomato, cucumber, and had an excellent recovery of 98–102.8 %.