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1.
A novel turn-on rhodamine B-based fluorescent chemosensor ( RBCS) was designed and synthesized by reacting N-(rhodamine B)lactam-1,2-ethylenediamine and carbon disulfide. Upon addition of Fe 3+ in EtOH/H 2O solution (2:1, v/v, HEPES buffer, 0.6?mM, pH 7.20), the RBCS displayed a significant fluorescence enhancement at 582?nm and a dramatic color change from colorless to pink, which can be detected by the naked eye. Significantly, the RBCS exhibited a highly selective and sensitive ability toward Fe 3+. The detection limit of the probe was 2.05?×?10 ?7?M. Job's plot indicated the formation of 1:1 complex between the RBCS and Fe 3+. Moreover, the practical use of the RBCS is demonstrated by its application in the detection of Fe 3+ in HeLa cells. 相似文献
2.
A new lawsone-based azo-dye 2-hydroxy-3-((pyridin-2-ylmethyl)diazenyl)naphthalene-1,4-dione ( 1) was synthesized and applied for sensing of metal ions. Receptor 1 showed selective fluorescent and colorimetric response for the detection of Cu 2+ and Fe 3+ over other tested metal ions. The fluorescence intensity of 1 was significantly quenched allowing detection of Fe 3+ and Cu 2+ down to 0.61 and 6.06 μM, respectively. The binding has been established by fluorescence spectroscopic method. Receptor 1 provided a 1?:?1 binding scaffold for recognition of Fe 3+ and Cu 2+ ions with the association constant of 3.33 × 10 6 and 3.33 × 10 5 M ?1, respectively. The B3LYP/6-31G/LANL2DZ method was employed for the optimization of 1 and 1·Fe 3+ and 1·Cu 2+. 相似文献
3.
A furan-2-carbonyl chloride modified rhodamine B derivative (RBFC) has been designed and synthesized. The probe RBFC exhibited excellent sensitivity and selectivity for detection of Fe 3+ with a 1:1 stoichiometry over other tested metal ions in a MeOH/H 2O (1:1, v/v, pH 7.36, HEPES buffer, 1.3?mM) solution. The association constant and the detection limit were calculated to be 7.28?×?10 3?M ?1 and 0.437?μM based on fluorescence titration analysis. Furthermore, the probe RBFC was successfully applied in living cells, and the results indicated that the probe could monitor intracellular Fe 3+ in MCF-7 cells. 相似文献
4.
By rationally introducing glutathione functionalized 1, 8–naphthalimide, a novel fluorescent chemosensor ( NG) was successfully synthesized. NG can high selectively and sensitively recognize Fe 3+/Hg 2+ ions through quenching of fluorescence among all kinds of common metal ions in aqueous medium. The binding stoichiometry ratio of NG–Fe3+ is verified as 2:1and NG–Hg2+ as 1:2 confirmed by Job's plot method, FT-IR, 1H NMR and ESI–MS spectrum, and the possible sensing mechanism were also proposed. The chemosensor NG toward Fe 3+ and Hg 2+ displays the excellent advantages of high selectivity and sensitivity, low detection limits (7.92?×?10 ?8 and 4.22?×?10 ?8?M), high association constants (3.37?×?10 8 and 8.14?×?10 4?M ?2), instataneous response (about 10s) and wide pH response range (3.0–8.0). Importantly, the chemosensor NG was successfully applied to determine Hg 2+ in tap water. Meanwhile, the test strips based on NG were prepared, which could conveniently and efficiently detect Fe 3+ and Hg 2+. Moreover, the complex of NG and Fe 3+ ( NG–Fe3+) showed high selectivity and sensitivity for H 2PO 4 ̄ over many other anions in the same medium. 相似文献
5.
A novel compound hexa-rhodamine substituted phosphazene (HRP) with six active centers on a cyclotriphosphazene ring was synthesized using the alkyne-azide “click” reaction. The structure of HRP was characterized using spectroscopic techniques. The optical sensor properties of HRP for metal ions were investigated using UV-Vis and Fluorescence spectroscopy. It was determined that HRP is a selective sensor with colorimetric and fluorescent properties for Fe 3+ ions. Limit of detection (LOD) of HRP was determined as 6.94?×?10 ?9 M using fluorescence intensities in the presence of different concentrations of Fe 3+ ions. It was determined that HRP-Fe 3+ complex has high quantum yield and excellent photostability. 相似文献
6.
2,2′‐Bisbenzimidazole derivative ( L ) was designed as a fluorescent chemosensor for Fe 3+. This structurally simple chemosensor displays significant fluorescence quenching with increasing concentrations of Fe 3+. L exhibited high selectivity and antidisturbance for Fe 3+ among environmentally relevant metal ions in aqueous media. The method of Job's plot indicated the formation of 1:2 complex between L and Fe 3+, and the possible binding mode of the system was also proposed. In addition, further study demonstrates the detection limit on fluorescence response of the sensor to Fe 3+ is down to 10 ?7 mol·L ?1 range. The binding mode was investigated by fluorescence spectra, ESI‐MS, IR data, 1H NMR, 13C NMR and crystal data. 相似文献
7.
A type of fluorescent–magnetic dual‐function nanocomposite, Fe 3O 4@SiO 2@P‐2, was successfully obtained by Cu +‐catalyzed click reaction between acetylene (C?C? H)‐substituted carbazole‐based conjugated polymer ( P‐2) and azide‐terminated silica‐coated magnetic iron oxide nanoparticles (Fe 3O 4@SiO 2–N 3). Optical and magnetization analyses indicate that Fe 3O 4@SiO 2@P‐2 exhibits stable fluorescence and rapid magnetic response. The fluorescence of Fe 3O 4@SiO 2@P‐2 was quenched significantly in the presence of I? and gave a detection limit (DL) of ~8.85 × 10 ?7 M. Given the high binding constant and matching ratio between Hg 2+ and I?, the fluorescence of Fe 3O 4@SiO 2@P‐2/ I? complex recovered efficiently with the addition of Hg 2+. A DL of ~4.17 × 10 ?7 M was obtained by this probing system. Recycling of Fe 3O 4@SiO 2@P‐2 probe was readily achieved by simple magnetic separation. Results indicate that Fe 3O 4@SiO 2@P‐2 can be used as an “on–off–on” fluorescent switchable and recyclable Hg 2+ probe. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 3636–3645 相似文献
8.
A new chemosensor based on coumarin FB has been designed and synthesized for the detection of Fe 3+ and PPi. FB displayed a high affinity to Fe 3+ in the presence of other competing cations. The resulting FB-Fe 3+ complex displayed highly sensitivity to PPi via Fe 3+ displacement approach. The Fe 3+ and PPi recognition processes is rapid and reversible, the detection limits of FB to Fe 3+ and FB-Fe 3+ complex to PPi were estimated to be 8.73?×?10 ?8?M and 1.25?×?10 ?8?M, respectively. The good biocompatibility of FB enables the investigation of fluorescent response for Fe 3+ and PPi in living cells by confocal microscope. A B3LYP/6-31G(d,p) basis set was employed for optimization of FB and FB-Fe 3+ complex. 相似文献
9.
The reaction of [Ni 3(dpa) 4(ClO 4) 2] with 1,4-benzenedicarboxylate through diffusion of layered-solution led to the precipitation of 1, {[Ni 3(dpa) 4(1,4-bdc)]?·?0.5H 2O]} n, where dpa ? is 2,2′-dipyridylamido anion, which was characterized by IR, elemental analysis, MS, fluorescence spectrum, TG analysis, and magnetic measurement. Extension of the metal string complex by assembly of [Ni 3(dpa) 4] 2+ and 1,4-bdc 2? gives a 1-D polymeric structure, in which the axial 1,4-bdc 2? influences the Ni?···?Ni distances, fluorescence emission, and magnetism. 相似文献
10.
A long wavelength emission fluorescent (612 nm) chemosensor with high selectivity for H 2PO 4? ions was designed and synthesized according to the excited state intramolecular proton transfer (ESIPT). The sensor can exist in two tautomeric forms ('keto' and 'enol') in the presence of Fe 3+ ion, Fe 3+ may bind with the 'keto' form of the sensor. Furthermore, the in situ generated GY‐Fe 3+ ensemble could recover the quenched fluorescence upon the addition of H 2PO 4? anion resulting in an off‐on‐type sensing with a detection limit of micromolar range in the same medium, and other anions, including F ?, Cl ?, Br ?, I ?, AcO ?, HSO 4?, ClO 4? and CN ? had nearly no influence on the probing behavior. The test strips based on 2‐[2‐hydroxy‐4‐(diethylamino) phenyl]‐1 H‐imidazo[4,5‐ b]phenazine and Fe 3+ metal complex ( GY‐Fe 3+ ) were fabricated, which could act as convenient and efficient H 2PO 4? test kits. 相似文献
11.
Two low cytotoxic fluorescence probes Rb1 and Rb2 detecting Fe 3+ were synthesized and evaluated. Rb1 and Rb2 exhibited an excellent selectivity to Fe 3+, which was not disturbed by Ag +, Li +, K +, Na +, NH 4+, Fe 2+, Pb 2+, Ba 2+, Cd 2+, Ni 2+, Co 2+, Mn 2+, Zn 2+, Mg 2+, Hg 2+, Ca 2+, Cu 2+, Ce 3+, AcO ?, Br ?, Cl ?, HPO 42?, HSO 3?, I ?, NO 3?, S 2O 32?, SO 32? and SO 42? ions. The detection limits were 1.87 × 10 ?7 M for Rb1 and 5.60 × 10 ?7 M for Rb2, respectively. 1:1 stoichiometry and 1:2 stoichiometry were the most likely recognition mode of Rb1 or Rb2 towards Fe 3+, and the corresponding OFF–ON fluorescence mechanisms of Rb1 and Rb2 were proposed. 相似文献
12.
Effects of several electron acceptors (Fe 3+, Cu 2+, Cr(VI), and H 2O 2) on phenol degradation in anodic contact glow discharge electrolysis have been investigated. Results show that the electron acceptors have positive effects on phenol removal, with the sequence of Fe 3+?>?Cr(VI)?>?H 2O 2?>?Cu 2+. Under conditions of voltage 500?V and current 100?mA, 100?mg/L phenol can be removed with 10?min of discharge treatment in the presence of 1.0?mmol/L Fe 3+, while without any additive only 35?% of phenol is removed in 30?min. The mechanism of the degradation enhancement was discussed based on the reactions taking place in the presence of the different additives. 相似文献
13.
The influence of different ions NO 3 ? and SO 4 2? on the carbon steel corrosion in ammonium chloride was investigated using mass loss measurements and potentiodynamic polarization. Corrosion products were analyzed using X-ray photoelectron spectroscopy (XPS) and simultaneous thermal and differential scanning calorimetry (TG/DSC). XPS analysis shows that the main product of corrosion is a non-stoichiometric Fe 3+ oxyhydroxide, consisting of a mixture of FeO(OH) and FeO(OH) containing inclusions of these anions, species such as Fe 3+O(OH,Cl ?); Fe 3+O(OH,SO 4 2?); and Fe 3+O(OH,NO 3 ?). TG/DSC confirms the decomposition of the rusty products formed by chemical corrosion, compounds like Fe 3+ oxyhydroxides, with β-FeOOH as the major phase, crystal structure of which may contain Cl ?, NO 3 ?, and SO 4 2?—e.g., akaganeite [Fe 3+O(OH,A)]. 相似文献
14.
Solution‐dispersible hyperbranched conjugated polymer nanoparticles (FT‐HBCPNs) consist of an intrinsic crosslinked rigid skeleton structure of both 9,9‐dihexyl‐fluorene and triphenylamine repeating units, and are synthesized via the miniemulsion Suzuki polymerization, and FT‐HBCPNs for highly selective and sensitive Fe 3+ fluorescent detection and their application in logic gate at molecular level are successfully developed. FT‐HBCPNs with an average particle size of 10.6 nm can disperse in common organic solvents. FT‐HBCPNs show high selectivity and sensitivity for Fe 3+ over other commonly co‐existent metal ions in THF solution with a detection limit of 3.65 × 10 ?8 mol L ?1. Furthermore, homogeneous transparent thin films of FT‐HBCPNs developed by a simple spin‐coating method can be reversibly quenched by Fe 3+ with a detection limit of 3.09 × 10 ?7 mol L ?1. Using Fe 3+ and EDTA as chemical inputs and the fluorescence intensity signal as outputs, FT‐HBCPNs films can be utilized as a logic gate at molecular level. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3694–3700 相似文献
15.
Highly transparent ultrathin films (UTFs) were fabricated via layer-by-layer assembly of 110-Phenanthroline monohydrate (Phen)–8-hydroxyquinoline (Hq)–Al3+(Phen–Hq–Al), polyvinyl alchol(PVA) and Mg–Al-layered double hydroxide (LDH)nanosheets. UV–visible absorption and fluorescence spectroscopy showed regular growth of UTFs increasing the numbers of assembly. The structure and morphology of Mg–Al-layered double hydroxide and UTFs were measured by Fourier transform infrared spectroscopy, XRD and SEM. We found that it can detect Fe3+ ion with relative selectivity and high sensitivity (Ksv?=?2.214?×?104 M?1) which indicates that UTFs can be a potential fluorescent probe for selectively of the Fe3+ ion. 相似文献
16.
A fluorescent Al 3+ chemo-sensor, 1-phenyl-3-methyl-5-hydroxypyrazole-4-acetone-(3′,4′-dimethylpyrrole-2′-formyl) hydrazone ( L), has been synthesized and characterized. L can detect Al 3+ in ethanol solution with a significant fluorescence enhancement of a turn-on ratio over 155-fold due to the formation of a 1?:?1 complex which is based on the molar ratio between L and Al 3+ ions, and the 1?:?1 stoichiometric complexation can be obtained from density functional theory calculations. No significant interference of other metal ions such as Na +, K +, Mg 2+, Ca 2+, Ni 2+, Zn 2+, Cd 2+, Co 2+, Cu 2+, Fe 3+, Cr 3+, Pb 2+, and Ag + was found. The detection limit for Al 3+ was 5?×?10 ?9?M in ethanol. 相似文献
17.
To design a probe with “turn-on” sensing, nitrogen and sulfur co-doped carbon quantum dots (N, S-CQDs) were prepared and screened against some metallic cations to first induce “turn-off” fluorescence. The ferric iron (Fe 3+) was shown to be the most responsive and effective in the fluorescence quenching of the N, S-CQDs based on a proposed photo-induced electron transfer mechanism. In addition, the fluorescence of N, S-CQDs-Fe 3+ system was well recovered using N-acetyl- l-cysteine (NAC) (turn-on) due to a redox reaction, suggesting that the N, S-CQDs-Fe 3+ system acts as a highly sensitive and selective sensor for the determination of N-acetyl- l-cysteine with a low limit of detection equal to 65.0?nmol/L and wide linear ranges from 0.67 to 25.56 and 25.56 to 193.55?μmol/L. The “turn-off/on” fluorescence method was successfully employed to monitor N-acetyl- l-cysteine in pharmaceutical products and human urine samples with a recovery range from 99.2 to 101.3%. In addition, the fluorescence switch properties of the nitrogen and sulfur co-doped carbon quantum dots were also investigated by alternate additions of Fe 3+ and N-acetyl- l-cysteine. 相似文献
18.
A novel chelating ligand, 2,4-[bis-(2,4-dihydroxybenzylidene)]-dihydrazinoquinazoline (DBHQ), was synthesized, and the fluorescence characteristics of its complex with metal ions were investigated.Thirty-five different metal ions were tested for the emission of fluorescence in the presence of DBHQ in aqueous solutions in a pH range of 3.0-10.5 (at a difference of 0.5 for each metal).It was observed that DBHQ fluoresces intensely at 470 nm with an excitation wavelength of 405 nm in the presence of Ga 3+ or Al 3+ in the pH range 3.0-4.0. The other metal ions did not show fluorescence with DBHQ. Although the presence of Cu 2+, Co 2+ and Fe 3+ decreased the fluorescence intensity of DBHQ-Ga 3+, the addition of a fluoride ion (NaF) recovered the fluorescence by masking the interfering ions. In addition, the fluoride ions were found to enhance the sensitive determination of Ga 3+ because the fluorescence intensity of DBHQ-Ga 3+ was further increased approximately 2.5-fold in the presence of F − ( ? = 0.658) from that in the absence of F − ( ? = 0.401). The fluoride ions also masked the Al 3+ ions, which emit fluorescence on chelation with DBHQ. Therefore, a selective and sensitive detection of Ga 3+ was achieved by using DBHQ in the presence of F −. The detection limit of Ga 3+ was approximately 50 nmol L −1 (3.5 ppb). The proposed method was applicable to determine Ga 3+ in river water. 相似文献
19.
A new diarylethene compound with a triazole-linked rhodamine 6G unit attached to the imino group ( 1O) was designed and synthesized. According to the test results, the solution color and fluorescence color of diarylethene can be modulated by lights and metal ions. The solution color could change from colorless to light purple when irradiated with UV light. When Cu 2+ was added to the diarylethene solution, the color of diarylethene solution became blue, the fluorescence color turned from dark to bright yellow. Although the solution color did not change by adding Fe 3+, its fluorescence color varied from dark to yellow. Moreover, it was found that the complex ratio of the diarylethene to Cu 2+ was 1:1 and the binding stoichiometry of the diarylethene to Fe 3+ was also 1:1 based on the data of NMR, MS, and other experiments. Based on these findings, photochromic figure of the diarylethene with UV/Vis light, Cu 2+ and Fe 3+ was constructed. Furthermore, the logic circuit was designed by input signals (ultraviolet stimulus, visible light stimulus, Cu 2+ (or Fe 3+) and EDTA) and an output signal (fluorescent intensity at 566?nm (or 575?nm)). 相似文献
20.
Fluorescent gold nanoclusters (Au-NCs) were synthesized by a one-pot method using 11-mercaptoundecanoic acid as a reducing and capping reagent. It is found that the red fluorescence of the Au-NCs is quenched by the introduction of Eu(III) at pH 7.0, but that fluorescence is restored on addition of phosphate. The Au-NCs were investigated by transmission electron microscopy and fluorescence photographs. The effect of pH on fluorescence was studied in the range from pH 6 to 10 and is found to be strong. Based on these findings, we have developed an assay for phosphate. Ions such as citrate, Fe(CN) 6 3?, SO 4 2?, S 2O 8 2?, Cl ?, HS ?, Br ?, AcO ?, NO 2 ?, SCN ?, ClO 4 ?, HCO 3 ?, NO 3 ?, Cd 2+, Ba 2+, Zn 2+, Mg 2+, and glutamate do not interfere, but ascorbate and Fe 3+ can quench Au-NCs fluorescence. The fluorescent nanocluster probe responds to phosphate in the range from 0.18 to 250 μM, and the detection limit is 180 nM. The probe also responds to pyrophosphate and ATP. Figure Off/on fluorescence sensor for phosphate based on Eu3+-modulated Au NCs thanks to the competition of oxygen-donor atoms from phosphate with those from the carboxylate groups was developed 相似文献
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