Details

Autor(en) / Beteiligte

• Wang, Huizhen
• Li, Xingdong
• Li, Jiajun
• Xie, Zhengfeng
• Chang, Guanjun

Titel

Synthesis of a “Turn-On” Mg2+ fluorescent probe and its application in hydrogel adsorption

Ist Teil von

• Journal of molecular structure, 2023-06, Vol.1281, p.135085, Article 135085

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •A compound HMN with an acylhydrazones structure was synthesized which can be used for detection and removal of Mg2+ in DMSO/H2O solution.•The probe HMN can specifically recognize Mg2+ in DMSO/H2O solution, with a color change from green to yellow, visible to the naked eyes.•The mechanism of probe HMN and its complex with Mg2+ were successfully optimized by density functional theory (DFT) calculations.•The adsorbent material PAM-HMN prepared by doping HMN into PAM gel can efficiently remove Mg2+ from water, with color change from violet to bright green clearly observed under UV light.•The probe HMN can be used for the quantitative detection of Mg2+ in actual water samples. A compound with a Schiff base structure, (E)-3-hydroxy-N'-(2-hydroxybenzaldehyde) (HMN), was synthesized using 3‑hydroxy-2-naphthoic acid hydrazine and 2-hydroxy-4-methoxybenzaldehyde as raw materials. The structure of probe HMN was characterized by 1H NMR, 13C NMR, HR-MS, IR and X-ray single crystal diffraction. This study found that the probe HMN can rapidly and highly selectively recognize Mg2+ in a water system with DMSO=1:9 (water system: 20% triethanolamine + 0.1 mol•L−1 L-cysteine). We used fluorescence spectroscopy and ultraviolet-visible spectroscopy to study the spectral properties of the probe HMN. The results showed that the combination of probe HMN and Mg2+ produced an obvious fluorescence enhancement effect which was negligibly affected by other metals and anions. After that, we used Job's curve, NMR titration, MS and DFT calculations to explore the binding mechanism of probe HMN and Mg2+, and found that they were coordinated in a 1:1 manner. We fitted a linear equation to different Mg2+ concentrations and fluorescence intensities, and the calculated detection limit (LOD) was 8.4802×10−8 mol/L. The standard addition and recovery experiments showed that the probe can be used for the qualitative detection of Mg2+ in water samples. A hydrogel (PAM-HMN) was prepared by doping HMN into polyacrylamide (PAM). We found that PAM-HMN had an efficient absorption performance for Mg2+, and the removal rate of Mg2+ from water reached 97.99%. The color change before and after adsorption of Mg2+ was easily identified by the naked eye under UV light. The microstructure and composition of PAM-HMN before and after adsorption were analysed by SEM-EDS. The probe and hydrogel derivatives have potential application value in environmental detection and pollution prevention. The experimental study of standard addition recovery showed that probe HMN could be used for the quantitative detection of Mg2+in actual water samples. [Display omitted]