A convenient colorimetric approach for visual detection of melamine in raw milk was realized by using gold nanoparticles(AuNPs)stabilized by an unsymmetrical terpyridyl zinc complex with a thymine fragment at one term...A convenient colorimetric approach for visual detection of melamine in raw milk was realized by using gold nanoparticles(AuNPs)stabilized by an unsymmetrical terpyridyl zinc complex with a thymine fragment at one terminal and a quaternary ammonium salt at the other.Even without pre-addition of melamine or relative additives,obvious color change from red to blue was observed by naked eye in the presence of trace amount of melamine,which was attributed to the alternation of aggregation state of AuNPs caused by the selective binding between the thymine fragment and melamine via triple hydrogenbonding interactions.Remarkably,the detection limit for melamine was as low as 2.4 ppb,providing a highly sensitive and efficient approach for the visual detection of melamine.展开更多
Two new compounds（1 and 2）based on indole were successfully synthesized and characterized.They display highly selective response to Fàin aqueous DMSO medium and pure DMSO with remarkable color and fluorescent c...Two new compounds（1 and 2）based on indole were successfully synthesized and characterized.They display highly selective response to Fàin aqueous DMSO medium and pure DMSO with remarkable color and fluorescent changes.Therefore,both receptors may serve as colorimetric sensors for Fàby visual detection.展开更多
A colorimetric anion receptor was synthesized by a simple method where the phenylhydrazone moiety was need as binding sites. The anion recognition via hydrogen-bonding interactions can be easily monitored by anion com...A colorimetric anion receptor was synthesized by a simple method where the phenylhydrazone moiety was need as binding sites. The anion recognition via hydrogen-bonding interactions can be easily monitored by anion complexation induced changes in UV-vis absorption spectra. Moreover, the hydrogen bond formation between the phenylhydrazone N-H and acetate or fluoride anion was described on the basis of ^1H NMR experiments.展开更多
A new colorimetric recognition receptor 1 based on the dual capability containing NH binding sites of selectively sensing anionic vip species has been synthesized. Compared with other halide anions, its UV/Vis absor...A new colorimetric recognition receptor 1 based on the dual capability containing NH binding sites of selectively sensing anionic vip species has been synthesized. Compared with other halide anions, its UV/Vis absorption spectrum in dimethyl sulfoxide showed the response toward the presence of fluoride anion with high selectivity, and also displayed dramatic color changes from colorless to yellow in the presence of TBAF （5 × 10^-5 mol/L）. The similar UV/Vis absorption spectrum change also occurred when 1 was treated with AcO^- while a little change with H2PO^-4 and OH^-. Receptor 1 has almost not affinity abilities to Cl^-, Br^- and I^-. The binding ability of receptor 1 to fluoride with high selectivity over other halides contributes to the anion size and the ability of forming hydrogen bonding. While the different ability of binding with geometrically triangular （AcO^-）, tetrahedral （H2PO^-4 ） and linear （OH^-） anions maybe result from their geometry configuration.展开更多
基金Financial support from the State General Administration of the People’s Republic of China for Quality Supervision and Inspection and Quarantine(No.2016QK122)the Science and Technology Projects of Jiangxi Province(No.20181BBH80007)+1 种基金Shanghai Institute of Quality Inspection and Technical Researchthe Department of Chemistry,Fudan University。
文摘A convenient colorimetric approach for visual detection of melamine in raw milk was realized by using gold nanoparticles(AuNPs)stabilized by an unsymmetrical terpyridyl zinc complex with a thymine fragment at one terminal and a quaternary ammonium salt at the other.Even without pre-addition of melamine or relative additives,obvious color change from red to blue was observed by naked eye in the presence of trace amount of melamine,which was attributed to the alternation of aggregation state of AuNPs caused by the selective binding between the thymine fragment and melamine via triple hydrogenbonding interactions.Remarkably,the detection limit for melamine was as low as 2.4 ppb,providing a highly sensitive and efficient approach for the visual detection of melamine.
基金the fnancial supports from NSF of China (Nos. 21031002 21202088, and 51073079)the China Postdoctoral Science Foundation (No. 2012M520570)the Fundamental Research Funds for the Central Universities
文摘Two new compounds（1 and 2）based on indole were successfully synthesized and characterized.They display highly selective response to Fàin aqueous DMSO medium and pure DMSO with remarkable color and fluorescent changes.Therefore,both receptors may serve as colorimetric sensors for Fàby visual detection.
基金Project supported by the National Natural Science Foundation of China （No. 20371028, 20671052） and the Natural Science Foundation of Tianjin of China （No. 023605811）.
文摘A colorimetric anion receptor was synthesized by a simple method where the phenylhydrazone moiety was need as binding sites. The anion recognition via hydrogen-bonding interactions can be easily monitored by anion complexation induced changes in UV-vis absorption spectra. Moreover, the hydrogen bond formation between the phenylhydrazone N-H and acetate or fluoride anion was described on the basis of ^1H NMR experiments.
文摘A new colorimetric recognition receptor 1 based on the dual capability containing NH binding sites of selectively sensing anionic vip species has been synthesized. Compared with other halide anions, its UV/Vis absorption spectrum in dimethyl sulfoxide showed the response toward the presence of fluoride anion with high selectivity, and also displayed dramatic color changes from colorless to yellow in the presence of TBAF （5 × 10^-5 mol/L）. The similar UV/Vis absorption spectrum change also occurred when 1 was treated with AcO^- while a little change with H2PO^-4 and OH^-. Receptor 1 has almost not affinity abilities to Cl^-, Br^- and I^-. The binding ability of receptor 1 to fluoride with high selectivity over other halides contributes to the anion size and the ability of forming hydrogen bonding. While the different ability of binding with geometrically triangular （AcO^-）, tetrahedral （H2PO^-4 ） and linear （OH^-） anions maybe result from their geometry configuration.
