Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluoresce...Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great challenge.Herein,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)ligand.TTP-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were proved.More importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).展开更多
The inclusion behaviors of three native or modified CDs including p-CD,2-hydroxypropyl-β-CD（2-Hp-β-CD） and 2,6-dimethyl-β-CD（Me-β-CD） toward 5-amino-6-methyl-2-benzimidazolone（AMBI） were comparatively invest...The inclusion behaviors of three native or modified CDs including p-CD,2-hydroxypropyl-β-CD（2-Hp-β-CD） and 2,6-dimethyl-β-CD（Me-β-CD） toward 5-amino-6-methyl-2-benzimidazolone（AMBI） were comparatively investigated by NMR and fluorescence titration in combination with IR spectra,X-ray diffractometry and scanning electron microphotographs.The experimental results jointly demonstrated that the phenyl ring of AMBI entered into the cavity of the CDs and located close to the narrow rims accompanied by the formation of the 1：1 inclusion complex with large stability constant in aqueous solution.The introduction of the hydroxypropyl unit to the host improved the solubility,ultimately effecting an obvious promoting in the fluorescence intensity and the stability constant展开更多
基金This study was financially supported by the National Natural Science Foundation of China(Nos.22001156 and 22271178)the Innovation Capability Support Program of Shaanxi(No.2022KJXX-88)the Technology Innovation Leading Program of Shaanxi(No.2020QFY07-05).
文摘Developing fluorescence porous probe for detecting and eliminating Cu^(2+) contamination in water or biosystem is an essential research project that has attracted considerable attention.However,improving the fluorescence detecting efficiency while enhancing the adsorption capacity of the porous probe is of great challenge.Herein,a bifunctional two-dimensional imine-based porous covalent organic framework(TTP-COF)probe was designed and synthesized from 1,3,5-tris(4-aminophenyl)benzene(TAPB)and 2,4,6-Triformylphloroglucinol(TP)ligand.TTP-COF displayed rapid detection of Cu^(2+)(limit of detection(LOD)=10 nmol·L^(−1) while achieving a high adsorption capacity of 214 mg·g^(−1)(pH=6)at room temperature with high reusability(>5 cycles).The key roles and contributions of highπ-conjugate and delocalized electrons in TABP and functional–OH groups in TP were proved.More importantly,the fluorescence quenching mechanism of TTP-COF was studied by density functional theory theoretical calculations,revealing the crucial role of intramolecular hydrogen bonds among C=N and–OH groups and the blocking of the excited state intramolecular proton transfer process in detecting process of Cu^(2+).
基金the National Natural Science Foundation of China (Nos. 21572177, 21272184, 21103137 and J1210057)the Shaanxi Provincial Natural Science Fund Project (No. 2015JZ003)+2 种基金the Xi’an City Science and Technology Project (No. CXY1511(3))the Northwest University Science Foundation for Postgraduate Students (No. YZZ14052)the Chinese National Innovation Experiment Program for University Students (No. 201510697004)
文摘The inclusion behaviors of three native or modified CDs including p-CD,2-hydroxypropyl-β-CD（2-Hp-β-CD） and 2,6-dimethyl-β-CD（Me-β-CD） toward 5-amino-6-methyl-2-benzimidazolone（AMBI） were comparatively investigated by NMR and fluorescence titration in combination with IR spectra,X-ray diffractometry and scanning electron microphotographs.The experimental results jointly demonstrated that the phenyl ring of AMBI entered into the cavity of the CDs and located close to the narrow rims accompanied by the formation of the 1：1 inclusion complex with large stability constant in aqueous solution.The introduction of the hydroxypropyl unit to the host improved the solubility,ultimately effecting an obvious promoting in the fluorescence intensity and the stability constant
