共查询到20条相似文献,搜索用时 15 毫秒
1.
LuTao He Qian Jiang RongZhao Gao XinShi Yang Wen Feng ShunZhong Luo YanQiu Yang Liang Yang LiHua Yuan 《中国科学:化学(英文版)》2014,57(9):1246-1256
A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using Lawesson's reagent. The X-ray structure of a trimeric analogue(13) revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations(Zn2+, Cd2+, Co2+, Ni2+, Pb2+, and Cu2+) and alkali and alkaline earth metal cations(Li+, Na+, K+, Rb+, Cs+, Ca2+, and Sr2+) demonstrated high efficiency(83.5%–96.4%) and superior selectivity for Cu2+ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order: 6 4 18 15. This is in stark contrast to the oligoamides that only gave much lower extractability(5.9%–16.4%), suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu2+. The complexation behavior of 4, 6, and 8 with Cu2+ was also examined by UV-Vis and NMR techniques. 相似文献
2.
A new benzoimidazole-naphthalimide derivative 4 was synthesized and its photophysical properties were studied. This compound showed highly selectively and sensitive colorimetric and ratiometric sensing ability for fluoride anion. 相似文献
3.
Cheng X Li S Jia H Zhong A Zhong C Feng J Qin J Li Z 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(6):1691-1699
A new series of intramolecular-charge-transfer (ICT) molecules (compounds 1, 2, and 3) were synthesized by attaching various electron-donating thiophenes groups to a triphenylamine backbone with an aldehyde group as the electron acceptor. Based on the protection reaction between ethanethiol and aldehyde, the corresponding dithioacetals (compounds S1, S2, and S3) were prepared to serve as novel colorimetric and fluorescent chemosensors for Hg(2+) ions. Also, compound S1 was further utilized to construct the chemical-reaction-based conjugated polymer probe (PS1) towards Hg(2+) ions. In the presence of as little as 10 nM Hg(2+), compound PS1 displayed an apparent change in the fluorescent intensity. The sensing processes were revealed to be mediated by ICT, as confirmed by time-dependent DFT calculations. Furthermore, compound S1 was successfully applied to microscopic imaging for the detection of Hg(2+) in HeLa cells with ratiometric fluorescent methods. 相似文献
4.
A dual colorimetric and luminescent sensor based on a heteroleptic ruthenium dye[Ru(Hipdpa)(Hdcbpy)(NCS)_2]~-·0.5H~+ 0.5[N(C_4H_9)_4]~+ Ru(Hipdpa) {where Hdcbpy = monodeprotonted-4,4'-dicarboxy-2.2'-bipyridineand Hipdpa = 4-(1H-imidazo[4,5-f][l,10]phenanthroIin-2-yl)-N,N-diphenylaniIine} for selective detection of Hg~(2+) is presented.The results of spectrophotometric titrations revealed an evident luminescence intensity enhancement(I/I_0 =11) and a considerable blue shift in visible absorption and luminescence maxima with the addition of Hg~(2+).The sensitive response of the optical sensor on Hg~(2+) was attributed to the binding of the electron-deficient Hg~(2+) to the electron-rich sulfur atom of the thiocyanate(NCS) ligand in the Ru(Hipdpa).which led to an increase in the energy gap between the highest occupied molecular orbital(HOMO) and the lowest unoccupied molecular orbital(LUMO).Accordingly,the blue shift in the absorption spectrum of Ru(Hipdpa) due to the binding of Hg~(2+) was obtained.Ru(Hipdpa) was found to have decreased Hg~(2+) detection limit and improved linear region as compared to di(tetrabutylammonium) ris-bis(isothiocyanato)bis(2,2'-bipyridine-4-carboxylic acid-4'-carboxylate)ruthenium(Ⅱ) N719.Moreover,a dramatic color change from pink to yellow was observed,which allowed simple monitoring of Hg~(2+) by either naked eyes or a simple colorimetric reader.Therefore,the proposed sensor can provide potential applications for Hg~(2+) detection. 相似文献
5.
A C3-ethynylated chlorophyll derivative was prepared from methyl pyropheophorbide-d possessing a 3-formyl group by treatment of Bestmann-Ohira reagent. The mono-substituted acetylene was subjected to coupling reactions at the terminal acetylenic carbon atom to form a series of π-extended chlorophyll derivatives. Replacement of the terminal hydrogen to phenyl, phenylethynyl and C3-chlorin-ethynyl caused red-shifts of their Qy (0,0) maxima from 675 to 679, 686, and 696 nm, respectively. Optical properties of C32-substituted 3-ethynyl-chlorophyll derivatives including chlorophyll dyads were investigated in comparison with those of their related compounds. Partial quenching of the fluorescence emission (Φflu=0.14) was observed for ortho-substituted dyad, compared to meta- (Φ=0.27) and para-dyads (Φ=0.29), suggesting a through-space interaction between the two chlorin macrocycles in a molecule. 相似文献
6.
Cholesterol-based Schiff base 1 has been designed and synthesised. The Schiff base 1 forms yellow coloured gel in DMF:H2O (2:1, v/v) and the gel is anion responsive. Among different anions, the gel phase of 1 is selectively transformed into sol in the presence of CN– ions and validates its visual sensing. 1H NMR, FTIR and HRMS spectroscopic techniques were adopted to study the gelation of 1 and its responsive behaviour towards anions. 相似文献
7.
Guangjie Song Di Jiang Lei Wang Xiangzhong Sun Hongtian Liu Yanqing Tian Meiwan Chen 《中国化学快报》2022,33(1):339-343
Colorimetric and fluorescent probes have emerged as a potent tool for pH sensing due to easy operation and high sensitivity. However, most of the existing bimodal probes require complicated synthesis,which greatly limits their wide applications. Herein, a simple fluorescent dye(called BFCUR) featuring a D-π-A-π-D conjugated system was developed from the natural polyphenol curcumin(CUR). BFCUR exhibited significant red-shift in UV absorption and fluorescence emission as pH increased because of th... 相似文献
8.
ZENG Xi WU Chong DONG Lei MU Lan XUE SaiFeng & TAO Zhu College of Chemistry Chemical Engineering Guizhou University Guiyang China Key Laboratory of Macrocyclic Supramolecular Chemistry of Guizhou Province Guiyang 《中国科学B辑(英文版)》2009,(4)
A new tripodal rhodamine B derivative 2 was designed and synthesized by tripodal trialdehyde and rhodamine B hydrazide for the first time. This derivative could be used as a fluorescent chemosensor for the selective and sensitive determination of copper(II) in Tris-HCl buffer and ethanol aqueous mixed media. Under the optimum conditions described herein,fluorescence enhancement at 557/577 nm was linearly related to the concentration of copper(II) in the range of 0.10 to 10.00×10-5 mol·L-1,with a corre-latio... 相似文献
9.
Jiangao Li Hanlin Ou Jing Li Xiaodi Yang Congwu Ge Dan Ding Xike Gao 《中国科学:化学(英文版)》2021,(12):2180-2192
Semiconducting polymers (SPs) with intensive near-infrared (NIR) absorption and high photothermal conversion efficiencies have been employed as a new generation... 相似文献
10.
In an attempt to obtain a model of copper(II) ion-selective sensors, a new 1,8-naphthalimide-based fluorescence chemosensor, N-allylamine-4-[(E)-4-(([2-aminoethyl]imino)methyl) benzene-1,3-diol]-1,8-naphthalimide (NABN), was designed and synthesized. The sensor NABN is fully characterized by melting point analysis, fourier transform infrared spectra, Ultraviolet–visible (UV–vis) spectra, fluorescence spectra, 1H NMR and 13C NMR spectroscopy, and mass spectrometry. NABN showed an unrivaled sensing behavior and an ardent selectivity toward copper(II) ion over other competitive metal ions tested in solution (N,N-Dimethylformamide (DMF)/Tris–HCl buffer, 1:1, v/v, pH = 7.2). The sensor showed a linear fluorescence quenching toward copper(II) ion in the range 0–50 μM, with a detection limit of 1.92 × 10−7 M estimated. Job's method indicated the formation of a 2:1 coordinative mode of the sensor with copper(II) ion with a high threshold of binding constant of 4 × 1012 M−1. Combining the above results, the quenching response of NABN toward Cu(II) ions could be ascribed to the strong, intrinsic paramagnetic behavior of Cu(II). 相似文献
11.
In this Letter, we synthesize highly soluble push–pull type fluorescent 2-(2-thienyl)benzothiazole dyes and evaluate their photophysical properties. The key step is the synthesis of 2-(5′-bromothien-2′-yl)-6-alkoxybenzothiazole (2) via oxidative cyclization of 2-thienylthioanilide using PhI(OAc)2 as the oxidant. The target dyes could be easily synthesized by the Suzuki–Miyaura cross-coupling reaction of 2 and an appropriate π-donor. The photophysical properties of the 2-thienylbenzothiazole chromophore were controlled by the π-donor moiety. It was found that 2 exhibited large Stokes shifts (5345 cm−1) and a high quantum efficiency for fluorescence (ΦF = 0.94 in CH2Cl2). Therefore, it can be expected to be a useful photofunctional material in liquid crystal laser dyes and nonlinear optical materials. 相似文献
12.
《Arabian Journal of Chemistry》2022,15(8):104000
A fast, simple, sensitive, and selective colorimetric method for the detection of Cu2+ was developed using Prussian blue/Turnbull’s blue nanoparticles (PBNPs/TBNPs) as the probe. The colorimetric sensor is based on the following principle. Cu2+ can induce the aggregation of L-cysteine (L-cys) modified-PBNPs/TBNPs (L-cys-PBNPs/TBNPs), resulting in an obvious red shift of its maximum absorption peak. Thus, the concentration of Cu2+ can be determined based on the peak shift in the UV–Vis spectra. The optimal pH, concentration of L-cys, reaction temperature between L-cys-PBNPs/TBNPs and Cu2+, the formation time of L-cys-PBNPs/TBNPs, and the reaction time between L-cys-PBNPs/TBNPs and Cu2+ of the method were determined to be pH 4.5, 2.0 mM, 20 °C, 5.0 min, and 2.0 min, respectively. A good linearity for the colorimetric determination of Cu2+ at the range of 0.25–2.5 μM (R2 = 0.986) was obtained, with a limit of detection (LOD) of 0.12 μM. Moreover, the negligible response of other metal ions demonstrates good selectivity and specificity of the sensor. In addition, the method was employed in the detection of Cu2+ in lake water samples, and the spiked recoveries are in the range of 96.7–106.6% with a relative standard deviation less than 7.4%. Therefore, the colorimetric method is applicable for Cu2+ detection in real water samples of high sensitivity and selectivity. 相似文献
13.
A new selective Zn^2+ fluorescent chemosensor, o-vanillin-4-ethoxybenzoylhydrazone (1), was designed and prepared. Free 1 mainly displayed very weak fluorescence at 480 nm upon excitation at 403 nm. It displayed high selectivity for Zn^2+ and had a 518- fold fluorescent enhancement upon binding of Zn^2+, while the other cation ions had only little influence on the fluorescence of 1. Mechanism of enhancement of l's fluorescence by Zn^2+ was briefly discussed. 相似文献
14.
《Arabian Journal of Chemistry》2022,15(11):104176
In this work, a new highly selective and sensitive fluorescent sensor for detecting Cu2+ was developed based on rhodamine fluorophore. It displayed strong fluorescence “turn-on” effect upon addition of Cu2+, and possessed the function of naked eye recognition. The fluorescence enhancement also enabled the sensor to quantitatively analyze Cu2+ due to the formation of a stable 1:1 metal–ligand complex in a short time, and the complex possesses relatively good pH stability. In addition, the density functional theory calculations were adopted to investigate the molecular orbitals as well as the spatial structure. Simultaneously, the cell imaging and zebra fish experiments provided a broader application prospect in biological system. 相似文献
15.
Xiangcao Li Xuejian Xing Shaojing Zhao Shaohua Zhu Benhua Wang Minhuan Lan Xiangzhi Song 《中国化学快报》2022,33(3):1632-1636
Benzoyl peroxide(BPO) has been added in wheat flour because of its bleaching effect. However, the abnormal used BPO has caused increasing concern due to its strong oxidization capability which may have adverse effects on living organisms. Herein, we present a carbon dot(CD)-based fluorescent and colorimetric probe for visually, sensitively and selectively sensing BPO. The addition of BPO could quench the red fluorescence of CDs peaked at 622 and 677 nm, and decrease the absorbance at 613 nm, whi... 相似文献
16.
Water-soluble cadmium sulfide (CdS) quantum dots (QDs) capped by mercaptoacetic acid were synthesized by aqueous-phase arrested
precipitation, and characterized by transmission electron microscopy, spectrofluorometry, and UV-Vis spectrophotometry. The
prepared luminescent water-soluble CdS QDs were evaluated as fluorescence probes for the detection of highly reactive hydrogen
selenide ions (HSe− ions). The quenching of the fluorescence emission of CdS QDs with the addition of HSe− ions is due to the elimination of the S2− vacancies which are luminescence centers. Quantitative analysis based on chemical interaction between HSe− ions and the surface of CdS QDs is very simple, easy to develop, and has demonstrated very high sensitivity and selectivity
features. The effect of foreign ions (common anions and biologically relevant cations) on the fluorescence of the CdS QDs
was examined to evaluate the selectivity. Only Cu2+ and S2− ions exhibit significant effects on the fluorescence of CdS QDs. With the developed method, we are able to determine the
concentration of HSe− ions in the range from 0.10 to 4.80 μmol L−1, and the limit of detection is 0.087 μmol L−1. The proposed method was successfully applied to monitor the obtained HSe− ions from the reaction of glutathione with selenite. To the best of our knowledge, this is the first report on fluorescence
analysis of HSe− ions in aqueous solution.
Figure CdS quantum dots as fluorescence probes for the sensitive and selective detection of highly reactive HSe- ions in aqueous
solution 相似文献
17.
A series of new heterocyclic chromophores 3-6 were synthesized in moderate to excellent yields by condensation of 5,6-phenantroline-dione with formyl-thiophene derivatives 1-2 in the presence of ammonium acetate in glacial acetic acid. These chromophores possess an (oligo)thienyl π-conjugated system attached to an imidazo-phenanthroline moiety. These derivatives were evaluated concerning their solvatochromic properties, thermal stabilities, and molecular optical nonlinearities. 相似文献
18.
With current concerns of the global threat from tuberculosis, it has become important to rapidly identify the bacteria. Traditional technologies involving isolation and amplification of the pathogenic bacteria are complicated and time-consuming. In this work, we describe a sensitive NMR-based detection method to identify bacteria via bacteria-induced self-assembly of magnetic nanoparticles. Bacillus Calmette-Guérin (BCG) was used as a surrogate for Mycobacterium tuberculosis. We prepared the probes by covalent immobilization of the anti-BCG monoclonal antibody onto carboxylic acid-functionalized magnetic nanoparticles. Once a solution containing BCG was introduced, the probes switched from a well dispersed state to an aggregated one, leading to a distinct and dose-dependent change in the spin-spin relaxation time (T2) of the solution. Thus the qualitative and quantitative detection method for BCG was established. The method provides specific detection of as few as 8 bacterial cells per millilitre in experimental samples within 1 hour, which will be promising for rapid detection of M. tuberculosis in clinical samples. 相似文献
19.
The π-extended rhodamine derivative aminobenzopyranoxanthene ABPX was synthesized by condensation of 2-4-diethylamino-2-hydroxybenzoylbenzoic acid with resorcinol in H2 SO4 solutionthen the derivative reacted with hydrazine monohydrate to obtain ABPX-hydrazideABPX-hyand its structure was characterized by ESI-MSFT-IR and NMR spectroscopy. The UV-Vis adsorption spectra at 500-600 nm tended to increase in the presence of Hg2+ in ABPX-hy ethanol solutionand the color of the solution changed from colorless to pink and gradually deepenedenabling visual colorimetric detection of Hg2+ by naked eye. Under the coexistence of 10 common metal ionsthe recognition of Hg2+ at 533 nm showed good anti-interference sensing performance. The absorption intensity of ABPX-hy had a good exponential relationship with the addition of Hg2+. The continuous coordination of Hg2+ to the N and O binding sites of ABPX-hy formed 21 stoichiometry of the ABPX-hy-Hg2+ complex. The orbital energy and spatial distribution levels of the closed-cycle to the open-cycle form were obtained by density functional theoryDFTcalculation. © 2022, Youke Publishing Co.,Ltd. All rights reserved. 相似文献
20.
Evaluation of α-pyrones and pyrimidones as photoaffinity probes for affinity-based protein profiling
α-Pyrones and pyrimidones are common structural motifs in natural products and bioactive compounds. They also display photochemistry that generates high-energy intermediates that may be capable of protein reactivity. A library of pyrones and pyrimidones was synthesized, and their potential to act as photoaffinity probes for nondirected affinity-based protein profiling in several crude cell lysates was evaluated. Further "proof-of-principle" experiments demonstrate that a pyrimidone tag on an appropriate scaffold is equally capable of proteome labeling as a benzophenone. 相似文献