A highly selective and sensitive europium-organic framework sensor for the fluorescence detection of fipronil in tea. (1st July 2023)

• Record Type: Journal Article
• Authors: Liu, Xinfang; Song, Junya; Zhang, Xiaoyu; Huang, Shijie; Zhao, Beibei; Feng, Xun
• Is Part Of: Food chemistry. Volume 413(2023)
• Publication Date: 2023-07-01
• Subjects: Metal organic complex -- Visual detection -- Tea-leaf -- Fluorescence test paper -- Smartphone; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2023.135639
• Languages: English
• ISSNs: 0308-8146

Abstract

Graphical abstract: Eu-TFPA-MOF was designed, characterized and used in the fluorescence detection of fipronil in tea. The red fluorescence of Eu-TFPA-MOF suspension was quenched by fipronil and the "turn off" approach exhibited high sensitivity and selectivity. In addition, a smartphone-assisted test strip was designed and applied in the on-site and visual detection of fipronil in tea samples. Highlights: Eu-TFPA-MOF was designed and characterized. The fluorescence detection of Eu-TFPA-MOF toward fipronil were studied. The quenching mechanism of Eu-TFPA-MOF toward fipronil was analyzed. The sensor was used for fipronil detection in real green tea and oolong tea. Smartphone-assisted test strip was designed and used for the detection of fipronil in real tea samples. Abstract: A europium-based metal organic framework (Eu-TFPA-MOF) was used for the fluorescence detection of fipronil in green tea and oolong tea for the first time. The red fluorescence of Eu-TFPA-MOF could be quenched significantly by low concentration (0.24 mM) of fipronil, and the "turn off" process exhibited quick response time (2 min), high sensitivity and selectivity, low detection limits (4.4 nM) and wide linear range (0–0.15 mM). The mechanism of fluorescence quenching was mainly attributed to static quenching process and the competitive absorption of excitation energy. Besides, the spiked and recovery test indicated that Eu-TFPA-MOF could be used in the fluorescence detection of fipronil in real green tea and oolong tea sample and the process had the advantages of simple pretreatment and satisfactory recoveries (98.33–106.17 %). More importantly, a simple, portable and low-cost smartphone-assisted test strip were designed for the visual detection of fipronil in real tea samples. The detection platform will be beneficial for tea quality safety and human heath, and is expected to be applied in other agricultural product safety field.