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1.
A series of monostyryl boron dipyrromethenes appended with an NO(4), NO(2)S(2), N(3)O(4), or N(3)O(2)S(2)-type ligand have been prepared and characterised. While the UV-Vis spectra of the former three compounds in CH(3)CN/H(2)O (2?:?3 v/v) do not respond towards a wide range of metal ions, the derivative with an N(3)O(2)S(2)-ligand exhibits a highly selective and sensitive spectral response towards Hg(2+) ions. The absorption band is blue-shifted by 40 nm due to inhibition of the intramolecular charge transfer process upon metal complexation. The fluorescence is also turned on giving a strong emission band at 572 nm. The colour changes can be easily detected by the naked eye. The results suggest that this compound serves as a promising colourimetric and fluorescent sensor for Hg(2+) ions in this mixed aqueous medium.  相似文献   

2.
A simple highly sensitive and selective turn-on fluorescent chemosensor L based on bis-Schiff-base for Pb2+ ions was synthesized and characterized by spectroscopic techniques. L having high binding affinity towards Pb2+ ions of 2.10 × 104 M?1 selectively detects Pb2+ ions with almost no interference among various competitive ions by a 11-fold fluorescent enhancement in CH3CN/H2O (95:5, v/v) solution over a wide pH range. Moreover, sensor L displayed a lower detection limit of 3.80 × 10?7 M, which is low enough for sensing sub-millimolar concentration of Pb2+ encountered practically.  相似文献   

3.
An organoselenium-based NSe(3) type of tripodal system 2 as a Hg(2+)-selective fluorescence "turn-on" probe is described. The "turn-on" fluorescence behavior of this selenotripod 2 is significant because it depends on Hg-Se bond formation and acts as a reporting unit for this system. The system exhibits immediate response (15 s) with a subnanomolar detection limit (0.1 nM) for the Hg(2+) ion. It efficiently detects both aqueous and nonaqueous Hg(2+) at 2 nM concentration.  相似文献   

4.
A new fluorescein-based chemodosimeter (II) for Hg2+ ion was designed and synthesized, and it displayed excellent selective and sensitive toward Hg2+ ion over other commonly metal ions in aqueous media. II was a colorless, non-fluorescent compound. Upon addition of Hg2+ to the solution of II, the thiosemicarbazide moiety of II would undergo an irreversible desulfurization reaction to form its corresponding oxadiazole (IV), a colorful and fluorescent product. During this process, the spirocyclic ring of II was opened, causing instantaneous development of visible color and strong fluorescence emission in the range of 500-600 nm. Based on the above mechanism, a fluorogenic Hg2+-selective chemodosimeter was developed. The fluorescence increase is linearly with Hg2+ concentration up to 1.0 μmol L−1 with a detection limit of 8.5 × 10−10 mol L−1 (3σ). Compared with the rhodamine-type chemodosimeter, II is more stable in aqueous media and exhibits higher sensitivity toward Hg2+. The findings suggest that II will serve as a practical chemodosimeter for rapid detection of Hg2+ concentrations in realistic media.  相似文献   

5.
We report herein the first diaminocyclopent-2-enone-based catalytic chemodosimeter (3) for naked-eye and turn-on fluorescent detections of Cu2+ in pure aqueous solution. Compound 3 easily made available from furan-2-carbaldehyde and 2-aminobenzoic acid was found to show a highly selective and sensitive response toward Cu2+ by way of Cu2+-coordination promoted formation of Stenhouse salt and subsequent decomposition to highly fluorescent 2-aminobenzoate.  相似文献   

6.
A naphthylthiourea-modified cyclodextrin (1) and its urea derivative (2) were synthesized, and their fluorescence behaviors in the presence of various metal ions were investigated. Significantly, 1 showed a highly sensitive and selective fluorescence sensing ability for Hg(2+) over other metal ions in both water and living cells. That is, the addition of Hg(2+) to an aqueous solution of 1 gave a significantly enhanced fluorescence at ~380 nm. In contrast, the addition of other metal ions induced negligible fluorescence changes. The possible mechanism may be due to the transformation of thiourea to urea by Hg(2+)-induced desulfurization in water.  相似文献   

7.
A selective and sensitive fluorescent chemosensor for Hg2+, which was composed of two aminonaphthalimide fluorophores and a receptor of 2,6-bis(aminomethyl)pyridine, was synthesized through the reaction of 2,6-bis(chloromethyl)pyridine and N-[2-(2-hydroxyethoxy)ethyl]-4-piperazino-1,8-naphthalimide. The chemosensor showed an about 17-fold increase in fluorescence quantum yield upon addition of 1 equiv of Hg2+ in neutral buffer aqueous solution, and the other common metal ions did not notably disturb the detection of Hg2+.  相似文献   

8.
《中国化学快报》2023,34(4):107725
Extensive application of nuclear energy has caused widespread environmental uranium contamination. New detection approaches without complicated sample pretreatment and precision instruments are in demand for on-site and in-time determination of uranyl ions in environmental monitoring, especially in an emergency situation. In this work, a simple and effective fluorescent sensor (Z)-N'-hydroxy-4-(1,2,2-triphenylvinyl)benzimidamide (TPE-A) with aggregation-induced emission (AIE) character was established and studied. It could realize to detect UO22+ via quenching the fluorescence of its aggregation-induced emission, with good selectivity and sensitivity. Such strategy shows a wide linear range from 5.0 × 10?8 mol/L to 4.5 × 10?7 mol/L (R2 = 0.9988) with exceptional sensitivity reaching 4.7 × 10?9 mol/L, which is far below the limit for uranium in drinking water (30 μg/L, ca. 1.1 × 10?7 mol/L) stipulated by the WHO. A response time less than four minutes make it rapid for uranyl ion measurement. It was applied for detection of uranyl ion in spiked river water samples with recoveries in the range of 98.7%-104.0%, comparable to those obtained by ICP-MS. With the advantages of portable apparatus, rapid detection process and high sensitivity, TPE-A can serve as a promising fluorescent sensor for the detection of UO22+ in environmental water samples.  相似文献   

9.
Wu JS  Hwang IC  Kim KS  Kim JS 《Organic letters》2007,9(5):907-910
[reaction: see text] N-(Rhodamine-6G)lactam-N'-phenylthiourea-ethylenediamine (1) was developed as a fluorescent and colorimetric chemodosimeter in aqueous solution with a broad pH span (5 approximately 10) and high selectivity toward Hg2+ but no significant response toward other competitive cations, such as Fe2+, Co2+, Ni2+, Cu2+, Zn2+, Pb2+, Cd2+, Ca2+, Mg2+, K+, Na+, etc. The Hg2+-promoted ring opening of spirolactam of the rhodamine moiety induced cyclic guanylation of the thiourea moiety, which resulted in the dual chromo- and fluorogenic observation (OFF-ON).  相似文献   

10.
11.
Ma X  Wang J  Shan Q  Tan Z  Wei G  Wei D  Du Y 《Organic letters》2012,14(3):820-823
A "turn-on" fluorescent chemosensor with excellent selectivity and satisfactory sensitivity on Hg(2+) detection in 100% water media has been established employing a carbohydrate based Ferrier carbocyclization reaction. The probe has also presented satisfactory results for the imaging of Hg(2+) ions in cells and organisms.  相似文献   

12.
A novel sensitive and specific Hg(2+) chemodosimeter, derived from 1',3'-dithiane-substituted 2,1,3-benzoxadiazole, displays "turn-on" fluorescent and colorimetric responses via an Hg(2+)-triggered aldehyde recovery reaction. Its potential to monitor Hg(2+) in living organisms has been demonstrated using zebrafish larvae.  相似文献   

13.
Abstract

A new coumarin-based probe (HgP) with two “S” groups was designed and synthesized The probe HgP exhibited a fast response time (<2?min) and high selectivity (DL, 2.2?×?10?7?mol/L). Furthermore, its capability of biological application was stu died, and the results showed that it could be applied to recognize Hg2+ in living cells (HK2 cells).  相似文献   

14.
A novel S,S′-diallyl carbohydrazonodithioate derivative 3 of rhodamine B hydrazone was developed as a chemodosimeter for selective detection of mercury ions based on Hg2+ promoted cyclization. The allyl groups of 3 play a key role in the binding and selection of Hg2+ ions. The probe responds selectively to Hg2+ over various other competitive cations with marked chromo- and fluorogenic changes. The formation of stable oxadiazole derivative 8 was a strong driving force for this high selectivity. Practically, this probe is more promising because of the remarkable high selectivity, faster response, low detection limit, and aqueous solubility of 3.  相似文献   

15.
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   

16.
ABSTRACT

In this work, a new turn-on fluorescent probe 1 for Hg2+ ions detection based on rhodamine B spirolactam was reported. Among tested metal ions, probe 1 shows high selectivity towards Hg2+ in the the mixture solution of methanol and 0.02 M HEPES buffer (V/V = 9:1, pH = 7.2). No absorption and emission band of probe 1 was observed in the range from 450 to 700 nm. While only addition of Hg2+ to probe 1 could lead to appearance of a new absorption band centered at 553 nm and a fluorescence emission band around 577 nm upon excitation at 520 nm. Moreover, it exhibits excellent linear relationship (R2 = 0.9993) between fluorescence intensity at 577 nm and the concentration of Hg2+ from 1.6 to 32 μM. The sensing mechanism was proven to be spirolactam ring open induced by Hg2+ through 1H NMR, MS, absorption and fluorescence spectra. In addition, probe 1 could detect Hg2+ in real water samples and on filter paper, which demonstrates its application in environment science.  相似文献   

17.
A Schiff-base fluorescent sensor, 7-methoxychromone-3-carbaldehyde-(3′,4′-dimethyl)pyrrole hydrazone (MCPH), was synthesized. The new sensor showed high selectivity for Al3+ over other metal ions examined in acetonitrile. Upon binding Al3+, a significant fluorescence enhancement with a turn-on ratio over 101-fold was triggered. The detection limit of MCPH for Al3+ was 2.5?×?10?7?mol?L?1.  相似文献   

18.
A rhodamine-based fluorescent and colorimetric chemodosimeter for the rapid detection of Hg2+ ions in aqueous media was developed. The system, which utilizes an irreversible Hg2+-promoted oxadiazole forming reaction, responds instantaneously at room temperature in a 1:1 stoichiometric manner to the amount of Hg2+. The selectivity of this system for Hg2+ over other metal ions is remarkably high, and its sensitivity is below 2 ppb in aqueous solutions.  相似文献   

19.
Li Y  Zhang X  Zhu B  Xue J  Zhu Z  Tan W 《The Analyst》2011,136(6):1124-1128
In this paper, CN-DPA was prepared as an effective colorimetric and fluorescent probe for copper ions (Cu(2+)) in aqueous solution. It exhibits good sensitivity and selectivity for Cu(2+) over other metal ions both in aqueous solution and on a simple colorimetric paper-made test kit. Upon addition of Cu(2+), a remarkable color change from purple to colorless was easily observed by the naked eye, and a fluorescence quenching was also determined. Furthermore, CN-DPA can be used to quantitatively detect Cu(2+). The linear range was 0-5 μM determined by absorption spectrometry. All these selective and sensitive results indicate that CN-DPA could meet the selective requirements for biomedical and environmental application and be sensitive enough to detect Cu(2+) in environmental water samples, even in drinking water, which has a limit of 20 μM defined by the U.S. Environmental Protection Agency.  相似文献   

20.
A rhodamine B derivative 4 containing a highly electron-rich S atom has been synthesized as a fluorescence turn-on chemodosimeter for Cu(2+). Following Cu(2+)-promoted ring-opening, redox and hydrolysis reactions, comparable amplifications of absorption and fluorescence signals were observed upon addition of Cu(2+); this suggests that chemodosimeter 4 effectively avoided the fluorescence quenching caused by the paramagnetic nature of Cu(2+). Importantly, 4 can selectively recognize Cu(2+) in aqueous media in the presence of other trace metal ions in organisms (such as Fe(3+), Fe(2+), Cu(+), Zn(2+), Cr(3+), Mn(2+), Co(2+), and Ni(2+)), abundant cellular cations (such as Na(+), K(+), Mg(2+), and Ca(2+)), and the prevalent toxic metal ions in the environment (such as Pb(2+) and Cd(2+)) with high sensitivity (detection limit < or =10 ppb) and a rapid response time (< or =1 min). Moreover, by virtue of the chemodosimeter as fluorescent probe for Cu(2+), confocal and two-photon microscopy experiments revealed a significant increase of intracellular Cu(2+) concentration and the subcellular distribution of Cu(2+), which was internalized into the living HeLa cells upon incubation in growth medium supplemented with 50 muM CuCl(2) for 20 h.  相似文献   

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