Pyrene-Based Fluorescent Porous Organic Polymers for Recognition and Detection of Pesticides

• Published in: Molecules (Basel, Switzerland) Vol. 27; no. 1; p. 126
• Main Authors: Yan, Zhuojun, Liu, Jinni, Miao, Congke, Su, Pinjie, Zheng, Guiyue, Cui, Bo, Geng, Tongfei, Fan, Jiating, Yu, Zhiyi, Bu, Naishun, Yuan, Ye, Xia, Lixin
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 26.12.2021; MDPI
• Subjects: Adsorption; Carbon; Chemical sensors; Chemoreceptors; Endocrine system; Fluorescence; fluorescence detection; Fourier transforms; Hydrocarbons; Microscopy; Organic pesticides; Pesticide residues; Pesticides; Pi-electrons; Poisoning; Polymers; porous organic polymers; pyrene group; Selectivity; Sensitivity; sensor; Solvents; Spectrum analysis; Trifluralin; sensor; pesticides; pyrene group; fluorescence detection; porous organic polymers
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27010126

Eating vegetables with pesticide residues over a long period of time causes serious adverse effects on the human body, such as acute poisoning, chronic poisoning, and endocrine system interference. To achieve the goal of a healthy society, it is an urgent issue to find a simple and effective method to detect organic pesticides. In this work, two fluorescent porous organic polymers, LNU-45 and LNU-47 (abbreviation for Liaoning University), were prepared using π-conjugated dibromopyrene monomer and boronic acid compounds as building units through a Suzuki coupling reaction. Due to the large π-electron delocalization effect, the resulting polymers revealed enhanced fluorescence performance. Significantly, in sharp contrast with the planar π-conjugated polymer framework (LNU-47), the distorted conjugated structure (LNU-45) shows a higher specific surface area and provides a broad interface for analyte interaction, which is helpful to achieve rapid response and detection sensitivity. LNU-45 exhibits strong fluorescence emission at 469 nm after excitation at 365 nm in THF solution, providing strong evidence for its suitability as a luminescent chemosensor for organic pesticides. The fluorescence quenching coefficients of LNU-45 for trifluralin and dicloran were 5710 and 12,000 (LNU-47 sample by ca. 1.98 and 3.38 times), respectively. Therefore, LNU-45 serves as an effective "real-time" sensor for the detection of trifluralin and dicloran with high sensitivity and selectivity.