Switchable aptamer-fueled colorimetric sensing toward agricultural fipronil exposure sensitized with affiliative metal-organic framework

• Published in: Food chemistry 2023-05, Vol.407, p.135115, Article 135115
• Main Authors: Zhang, Xinai, Zhou, Yue, Huang, Xueyue, Hu, Xuetao, Huang, Xiaowei, Yin, Limei, Huang, Qilin, Wen, Yunbo, Li, Bin, Shi, Jiyong, Zou, Xiaobo
• Format: Article
• Language: English
• Subjects: Affiliative nanozyme; Agricultural pesticide exposure; Agriculture; Aptamer; Colorimetric probe; Colorimetry - methods; Ecosystem; Food safety supervision; Humans; In-field monitoring; Limit of Detection; Metal-Organic Frameworks - chemistry; Oligonucleotides; Pesticides
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2022.135115

[Display omitted] •Affiliative and biomimetic ZIF-8 is used to design switchable colorimetric probe.•The aptamer-attached ZIF-8 preferred to adsorb TMB rather than ABTS.•The attached aptamer could fuel catalytic activity of ZIF-8 toward TMB oxidation.•Smartphone-based model allows for on-site fipronil assay in agricultural matrices.•The pragmatic platform expands application prospect in food safety supervision. Persistent usage of pesticides in agriculture has posed serious damage to overall ecosystem and human health, and thereby it is imperative to develop sensitive and efficient tools to evaluate residual pesticides in food and environmental setting. Herein, we reported a switchable colorimetric probe toward fipronil residue sensitized with aptamer-fueled catalytic activity of affiliative ZIF-8. Innovatively, it was found that the attached aptamer preferred to adsorb 3,3′,5,5′-tetramethylbenzidine (TMB) rather than 2,2-azinobis (3-ethylbenzothiazo-line-6-sulfonic acid) (ABTS), greatly promoting catalytic oxidation of ZIF-8 toward TMB for further improving sensitivity. Aiding with smartphone-based image acquisition, fipronil-responsive discoloration degree was converted into the ratio of green and blue (G/B) with limit of detection as low as 0.036 μM (0.016 μg·g−1). Moreover, it allowed for fipronil analysis in water, soil and vegetable samples with good recovery between 87 % and 110 %, verifying extension application prospect of the aptamer-fueled colorimetry for on-field pesticide evaluation in food safety supervision.