Impedimetric aptasensor based on highly porous gold for sensitive detection of acetamiprid in fruits and vegetables. (30th August 2020)

• Record Type: Journal Article
• Authors: Xu, Yiwei; Zhang, Wen; Shi, Jiyong; Li, Zhihua; Huang, Xiaowei; Zou, Xiaobo; Tan, Weilong; Zhang, Xinai; Hu, Xuetao; Wang, Xin; Liu, Chao
• Is Part Of: Food chemistry. Volume 322(2020)
• Publication Date: 2020-08-30
• Subjects: Acetamiprid -- Aptasensor -- Porous gold -- Aptamer -- Electrochemical impedance spectroscopy; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2020.126762
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: A novel electrochemical aptasensor was developed for the impedimetric determination of acetamiprid. The aptasensor was prepared by electrodeposition of highly porous gold and self-assembly of acetamiprid-binding aptamer. The aptasensor exhibited high sensitivity and selectivity for acetamiprid detection. The aptasensor was successfully applied to detect acetamiprid in fruits and vegetables. Abstract: A novel electrochemical aptasensor modified with highly porous gold and aptamer was prepared for the determination of acetamiprid in fruits and vegetables. Highly porous gold was synthesized by electroreduction at −4 V in an electrolyte containing 2.5 mol/L NH4 Cl and 10 mmol/L HAuCl4 . Acetamiprid-binding aptamer was immobilized on highly porous gold by self-assembly. Acetamiprid could be captured by aptamer on the sensing interface, resulting in an increment of electron transfer resistance. Thanks to the large specific surface area of highly porous gold and the high affinity of aptamer, the aptasensor exhibited a highly sensitive impedance response for acetamiprid. Under optimal condition, the aptasensor displayed a linear response for acetamiprid in the concentration range of 0.5–300 nmol/L, and the detection limit was 0.34 nmol/L. Furthermore, the aptasensor showed high selectivity, good reproducibility and stability. Finally, the aptasensor was applied for the determination of acetamiprid in fruits and vegetables with satisfactory results.