共查询到20条相似文献,搜索用时 15 毫秒
1.
A new 7-nitrobenz-2-oxa-1,3-diazole (NBD) based colorimetric and fluorescence chemosensor for Zn2+, an ion involved in many biological processes, was designed and synthesized. The NBD-probe 1 displays a red-to-yellow color change and an enhancement of fluorescent intensity in the presence of an aqueous solution of Zn2+ ions (pH 7.2). Internal charge transfer (ICT) and photoinduced electron transfer (PET) mechanisms are responsible for these changes. The practical use of this probe was demonstrated by its application to the biologically relevant detection of Zn2+ ions in pancreatic β-cells. 相似文献
2.
Liulei Ma Taohua Leng Kai Wang Chengyun Wang Yongjia Shen Weihong Zhu 《Tetrahedron》2017,73(10):1306-1310
A novel coumarin-based compound 1 featuring thiosemicarbazone as binding unit, was reported as a colorimetric and fluorescent probe for the detection of fluoride anion. The addition of F? to a solution of probe 1 in tetrahydrofuran resulted in evident naked-eye color change from green-yellow to orange-red under daylight and obvious fluorescence quenching within 3 s. And the detection limit toward F? was calculated to be as low as 2.16 × 10?7 mol/L. 1H NMR titrations proved that the interaction between 1 and fluoride ion: hydrogen bond at low fluoride ion concentration, deprotonation at high fluoride ion concentration. Besides, it exhibited highly sensitivity and selectivity for F? over other examined ions (Cl?, Br?, I?, AcO?, NO3?, HSO4?, H2PO4?) in tetrahydrofuran solution. 相似文献
3.
Acridinium salt based fluorescent and colorimetric chemosensor for the detection of cyanide in water
A new, selective chemosensor has been developed to detect cyanide in water at micromolar concentrations. The acridinium salt used in this sensor system is prepared in a single step from an acridine orange base. Detection is based on the irreversible, 1:1 stoichiometric, nucleophilic addition of cyanide to the 9-position of the acridinium ion. This process induces a large decrease in fluorescence intensity and a marked color change. The selectivity of the system in aqueous media for CN- over other anions is remarkably high. Also, the sensitivity of both the fluorescence- and colorimetric-based assay is below the 1.9 microM suggested by the World Health Organization (WHO) as the maximum allowable cyanide concentration in drinking water. Thus, the chemodosimeter should be applicable as a practical system for the monitoring of CN- concentrations in aqueous samples. [structure: see text] 相似文献
4.
Kyung Beom Kim Dong Min You Jun Hwi Jeon Yo Han Yeon Jong Ha Kim Cheal Kim 《Tetrahedron letters》2014
We have synthesized a new Schiff base 1, which detects Al3+ through fluorescence and naked eye in aqueous solution. The sensor 1 exhibited selective and sensitive recognition toward Al3+ via significant fluorescence enhancement (31-fold). Moreover, it showed a significant color change from colorless to yellow. The complex formation was proposed to be 1:1 ratio, based on the Job plot, ESI-mass spectrometry analysis, 1H NMR titration, and IR analysis. The detection limit was 1.00 μM, which is below the WHO acceptable limit (1.85 μM) in drinking water. In addition, the sensor 1 could be recyclable simply through treatment with a proper reagent such as EDTA. 相似文献
5.
Xianglin TangWeimin Liu Jiasheng WuWenwen Zhao Hongyan ZhangPengfei Wang 《Tetrahedron letters》2011,52(40):5136-5139
A TCNQ-based triphenylamine derivative (1) with strong intramolecular charge transfer (ICT) character was designed as a colorimetric sensor for thiols. Upon addition of thiols, the absorption spectrum of sensor 1 in aqueous solution was remarkably changed because the adduct of 1 with thiol decreased its ICT character. Sensor 1 showed highly selective and sensitive sensing ability toward thiols over other analytes. This selectivity could be easily observed by naked eyes, indicating that sensor 1 is a potential colorimetric sensor for thiols. 相似文献
6.
The synthesis and complexing properties of a calix[4]arene derivate (6) carrying two spirobenzopyran moieties are described. The addition of lanthanide ions resulted in significant UV-vis spectral shifts (68-84 nm) in visible region. It indicates that the synthetic receptor can recognize lanthanide ions by naked eyes over other cations including Na+, K+, Mg2+, Ca2+, Fe3+, Cu2+ and Zn2+. The mechanism of recognition was studied with 1H NMR, UV-vis spectra and emission spectra. The receptor may be applied to sense lanthanide ions. 相似文献
7.
Electrostatic interactions between anions and a new water-soluble, cationic, affinitychromic poly(3-alkoxy-4-methylthiophene) derivative provide a new tool for a selective optical detection method (colorimetric or fluorometric) for iodide ions. 相似文献
8.
A fluorescent and colorimetric receptor (L) for specific recognition of TNP was described. The origins of this remarkable affinity was disclosed by the crystal structure of corresponding host-guest complex L·TNP. 相似文献
9.
A new highly selective colorimetric chemosensor for Co(2+) was developed based on coumarin-conjugated thiocarbanohydrazone. The ligand senses Co(2+) in solution by changing its color from light yellow to deep pink. The sensor has been used in the development of practically viable colorimetric kits and as a staining agent for Co(2+) in microorganisms. 相似文献
10.
Sodium diethyldithiocarbamate (DDTC-Na) was demonstrated to be a new colorimetric cyanide chemosensor by utilizing an indirect
trick. First, some copper ions were added to the colorless aqueous solution of DDTC-Na. Then, the resultant brown solution
was studied upon the addition of different anions, including Cl−, I−, IO3−, SO42−, NO2−, Br−, H2PO4−, F−, SCN−, HSO4−, ClO4− and CN−. It was observed by naked eyes that the brown solution changed to colorless immediately after the addition of the trace cyanide,
but there were no changes towards other anions, making DDTC-Na a good selective cyanide chemosensor in pure water.
Supported by the National Natural Science Foundation of China (Grant Nos. 20674059 & 20402011) 相似文献
11.
A pyrene-based dual chemosensor for colorimetric detection of Cu2+ and fluorescent detection of Fe3+
Yuxin Guo Lei Wang Jiezhen Zhuo Bo Xu Xue Li Jianyu Zhang Zhiqiang Zhang Haijun Chi Yan Dong Gonghao Lu 《Tetrahedron letters》2017,58(42):3951-3956
A pyrene based chemosensor was designed and synthesized. The pyrene fluorophore was connected with a pyridine unit through a Schiff base structure to give the sensor (L). L was tested with a variety of metal ions and exhibited high colorimetric selectivities for Cu2+ and Fe3+ over other ions. Upon binding with Cu2+ or Fe3+, L showed an obvious optical color change from colorless to pink for Cu2+ or orange for Fe3+ over a wide pH range from 3 to 12. Moreover, the fluorescence of L at 370 nm decreased sharply after bonding with Fe3+, while other metal ions including Cu2+ had no apparent interference. Thus, using such single chemosensor, Cu2+ and Fe3+ can be detected independently with high selectivity and sensitivity. The limits of detection toward Cu2+ and Fe3+ were 8.5 and 2.0 μM, respectively. DFT calculation results also proved the formation of stable coordination complexes and the phenomenon of fluorescence quenching by Fe3+. Furthermore, L was also successfully used as a bioimaging reagent for detection of Fe3+ in living cells. 相似文献
12.
A novel vitamin B6 cofactor derived anion sensor L for the selective colorimetric detection of acetate has been developed by the condensation of pyridoxal and 2-aminothiophenol. The sensor L showed a noteworthy change in the visible region of the spectrum and was detected by the ‘naked-eye’ for both acetate and fluoride anions in DMSO but selectively for acetate in DMSO/H2O (88:12, v/v). The anion recognition ability of L was investigated by spectroscopic (UV–vis and 1H NMR) and DFT methods. 相似文献
13.
Honglei Mu 《Tetrahedron letters》2007,48(31):5525-5529
A novel two-channel metal ion sensor has been synthesized from macrocyclic dioxotetraamine and 1,8-naphthalimide derivative. The metal ion-selective signaling behaviors of the sensor were investigated. The sensor presented the selective coloration for Cu2+ and Hg2+ that can be detected by the naked-eye, respectively. Besides, the addition of Cu2+ and Hg2+ quenched the fluorescence of 1 obviously and the detection limit was found to be 3 × 10−7 M for Cu2+ and 7 × 10−7 M for Hg2+. This sensor can be utilized for the visual and spectroscopic detection of Cu2+ or Hg2+ in the presence of the other competing metal ions. 相似文献
14.
Herein, we unveiled the first zinc complex based chemosensor for cyanide (CN(-)). The changed visual color from light reddish orange to dark reddish orange, the enhanced fluorescence intensity at approximately 600 nm and the near-linear correlation A(495)/A(325)versus the cyanide concentration were observed after adding CN(-). 相似文献
15.
16.
Colorimetric azobenzene based chemosensors 1 and 2 were designed for detection of transition-metal ions such as Cu(II) under physiological pH conditions. The internal charge transfer (ICT) sensors are highly colored, absorbing in the green. For 1, the Cu(II) recognition gives rise to red-to-yellow color changes that are visible to the naked-eye and reversible upon addition of EDTA, whereas for 2, which lacks the aromatic o-methoxy chelating group, no such changes were observed. 相似文献
17.
A new tailor-made colorimetric chemosensor 1, containing pyridine and benzothiazole moieties connected through an azo (–N = N–) linkage has been synthesised. In 9:1 (v/v) aqueous THF (pH 7.0 HEPES buffer), it showed a conspicuous naked-eye colour change upon binding to Ni2+ (colourless to light green) and AcO? (colourless to orange) resulting in their ratiometric sensing. The cation and anion recognition property of the chemosensor 1 was monitored by UV–vis spectral analysis and 1H NMR titrations. 相似文献
18.
Zhou LL Sun H Zhang XH Wu SK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(1-2):61-65
The fluorescent compound N-substituted 2,6-bis(benzimidazol-2-yl)pyidine (1) has been synthesized. The fluorescent characteristics of the compound 1 and 2,6-bis(benzimidazol-2-yl)pyidine (2) and the complexes formed between the two compounds and different metal ions have also been investigated. The results show that the compound 1 possesses a specific ability to form complex with Cu(2+) ion, but the compound 2 have not such a property. It is proposed that the specific recognition ability of compound 1 to Cu(2+) may be attributed to the cyclic configuration of this compound in polar solvent. 相似文献
19.
Cheol Gyu Lee Seungyoon Kang Jinyoung Oh Min Sik Eom Jusung Oh Min-Gon Kim Woon Seob Lee Sukwon Hong Min Su Han 《Tetrahedron letters》2017,58(46):4340-4343
In this study, a colorimetric and fluorescent chemosensor for mercury ions (Hg2+) was developed. Cationic polydiacetylene (PDA) vesicles with a quaternary ammonium cation and iodide as a counterion show a blue-to-red color transition; the color change is accompanied by a fluorescence enhancement in selective response to Hg2+ ions because of a perturbation of the ene–yne conjugated backbone induced by counterion exchange. It allows for selective detection of Hg2+ with the naked eye and the sensor is used to determine Hg2+ concentrations in tap water samples. 相似文献
20.
Twenty natural amino acids can be distinguished with high fidelity using an array of indicator displacement assays in combination with a multivariate analysis. The array is easily constructed by mixing of commercially available building blocks at different pH. 相似文献