Synthesis and application of purine-based fluorescence probe for continuous recognition of Cu2+ and glyphosate

Xu Chen; Yanxia Mao; Anguan Wang; Linchuan Lu; Qi Shao; Chunhui Jiang; Hongfei Lu

doi:10.1016/j.saa.2023.123291

Synthesis and application of purine-based fluorescence probe for continuous recognition of Cu²⁺ and glyphosate

Spectrochim Acta A Mol Biomol Spectrosc. 2024 Jan 5:304:123291. doi: 10.1016/j.saa.2023.123291. Epub 2023 Aug 23.

Authors

Xu Chen¹, Yanxia Mao¹, Anguan Wang¹, Linchuan Lu¹, Qi Shao¹, Chunhui Jiang², Hongfei Lu³

Affiliations

¹ School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003, China.
² School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003, China. Electronic address: chemjiang@just.edu.cn.
³ School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang, Jiangsu 212003, China. Electronic address: zjluhf1979@just.edu.cn.

PMID: 37639808
DOI: 10.1016/j.saa.2023.123291

Abstract

In this study, a novel fluorescent sensor, N,N-dimethyl-4-((2-(8-m-ethyl-9-(naphthalen-1-yl)-9H-purin-6-yl)hydrazineylidene)methyl)aniline(PHA), which was constructed via Schiff base reaction of purine derivatives and dimethylaminobenzaldehyde. This probe showed significant selective fluorescence quenching of Cu²⁺, and accompanying with an increase in Cu²⁺ concentration and a change in solution color from colorless to yellow. The outstanding features of PHA include low detection limit (0.429 μM), strong anti-interference ability and fast response time. We further investigated the chelation mechanism of PHA and Cu²⁺ by Job's plot experiment, density generalization theory (DFT), and the probe PHA can form a 1:2 complex with Cu²⁺ ions, leading to a fluorescence quenching process, thus realizing the rapid detection of Cu²⁺. In addition, this new fluorescent sensor [PHA-Cu²⁺] can be used to detect pesticide residues in solution. When the [PHA-Cu²⁺] system was mixed with glyphosate solution, that a fluorescence recovering was observed. This may be because glyphosate chelates more strongly with Cu²⁺ ions, making the copper ions dissociated from the [PHA-Cu²⁺] system. The detection limit of the fluorescent sensor [PHA-Cu²⁺] for glyphosate was 18.77 nM. Finally, the sensor system has been successfully applied in fluorescence imaging of glyphosate in living cells.

Keywords: Fluorescence sensor; Glyphosate; Metal copper ions; Pesticide residues.