An in-situ strategy to construct uracil-conjugated covalent organic frameworks with tunable fluorescence/recognition characteristics for sensitive and selective Mercury(II) detection

Xi-Rui Deng; A-Wei Hu; Sheng-Qian Hu; Wen-Li Yang; Chen Sun; Sai-Jin Xiao; Gui-Ping Yang; Qiong-Qing Zheng; Ru-Ping Liang; Li Zhang; Jian-Ding Qiu

doi:10.1016/j.aca.2023.341056

An in-situ strategy to construct uracil-conjugated covalent organic frameworks with tunable fluorescence/recognition characteristics for sensitive and selective Mercury(II) detection

Anal Chim Acta. 2023 Apr 29:1252:341056. doi: 10.1016/j.aca.2023.341056. Epub 2023 Mar 6.

Authors

Affiliations

¹ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, PR China.
² State Key Laboratory of Nuclear Resources and Environment, East China University of Technology (ECUT), Nanchang, 330013, PR China.
³ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, PR China. Electronic address: zhangli8@ncu.edu.cn.
⁴ School of Chemistry and Chemical Engineering, Nanchang University, Nanchang, 330031, PR China; State Key Laboratory of Nuclear Resources and Environment, East China University of Technology (ECUT), Nanchang, 330013, PR China. Electronic address: jdqiu@ncu.edu.cn.

PMID: 36935154
DOI: 10.1016/j.aca.2023.341056

Abstract

Previous researches of covalent organic frameworks (COFs) have shown their potential as fluorescent probes, but the regulation of their optical properties and recognition characteristics still remains a challenge, and most of reports required complicated post-decoration to improve the sensing performance. In this context, we propose a novel in-situ strategy to construct uracil-conjugated COFs and modulate their fluorescence properties for sensitive and selective mercury(II) detection. By using 1,3,6,8-tetrakis(4-formylphenyl)pyrene (TFPPy) and 1,3,6,8-tetrakis(4-aminophenyl)pyrene (TAPPy) as fundamental blocks and 5-aminouraci (5-AU) as the functional monomer, a series of COFs (Py-COFs and Py-U-COFs-1 to Py-U-COFs-5) with tunable fluorescence were solvothermally synthesized through an in-situ Schiff base reaction. The π-conjugated framework serves as a signal reporter, the evenly and densely distributed uracil acts as a mercury(II) receptor, and the regular pores (channels) make the rapid and sensitive detection of the mercury(II) possible. In this research, we manage to regulate the crystalline structure, the fluorescence properties, and the sensing performance of COFs by simply changing the molar ratio of precursors. We expect this research to open up a new strategy for effective and controllable construction of functionalized COFs for environmental analysis.

Keywords: Covalent organic frameworks; Fluorescence; In-situ modification; Mercury(II) detection; Uracil.