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1.
A novel rhodamine based fluorescent chemosensor RQP was prepared and characterized by 1HNMR, 13CNMR and HR-MS. The properties of RQP were studied through UV–Vis spectroscopy and fluorescence spectroscopy. RQP showed highly selectivity toward Hg 2+ over other metal ions, including Ag +, Cd 2+, Cu 2+, Na +, Mg 2+, Ni 2+, Pb 2+, Fe 3+, and Zn 2+ in aqueous solutions. The recognition process is reversible and confirmed by EDTA experiment. 相似文献
2.
A colorimetric and fluorescent indicator based on cinnamamide group-containing rhodamine derivative was synthesized for the detection of Hg 2+. The rhodamine B and cinnamamide were connected via ethylenediamine as a bridging molecule through a condensation reaction to obtain a colorimetric and fluorescent indicator for the detection of Hg 2+ in H 2O-EtOH (4:1, v/v). The indicator was excellent in the selectivity of Hg 2+ and was almost unaffected by other common ions such as Na +, K +, Mg 2+, Fe 3+, Cu 2+, Zn 2+, Cr 3+. The Hg 2+-containing aqueous solution turned from colorless to red within 7 min after the addition of the indicator, and had an absorption peak at 564 nm in UV-vis, which implies a significant colorimetric phenomenon. Their characteristic peaks varied with the Hg 2+ content, and they reached a linear relationship at low concentrations. The binding stoichiometry proved to be 1:1. The lowest detection limit was 4.1?×?10 ?7 mol/L, ranging from acidic to neutral. 相似文献
3.
A irreversible Hg 2+ selective ratiometric fluorescence probe FR, a fluorescein fluorophore linked to a rhodamine B hydrazide by a thiourea spacer, was designed and synthesized. The developed
probe FR exhibited great ratiometric fluorescence enhancement and remarkable yellow-magenta color change toward Hg 2+ with excellent selectivity in aqueous acetone solution, and the ratiometric fluorescence response to Hg 2+ was not interfered by other metal cations including Fe 3+, Co 2+, Ni 2+, Cr 3+, Zn 2+, Pb 2+, Cd 2+, Ca 2+, Mg 2+, Ba 2+ and Mn 2+. The linear range and the detection limit of this supposed ratiometric fluorescence method for Hg 2+ were 0.0–10.0 × 10 −6 and 5 × 10 −8 M, respectively. 相似文献
4.
A nanosensor, based on 8-hydroxyquinoline functionalized graphene oxide, was developed for the fluorescence detection of Zn 2+. It showed high selectivity and sensitivity for Zn 2+ion in aqueous solution over other metal ions such as Li +, Na +, Ca 2+, Mg 2+, Al 3+, Cd 2+, Co 2+, Cu 2+, Hg 2+, Ni 2+, Pb 2+, Fe 2+, Fe 3+and Cr 3+. Due to the linearity of the emission intensity toward Zn 2+ concentration, fluorescent technique could be used for the detection of Zn 2+ ion even at very low concentrations. 相似文献
5.
In this paper, a new kind of colorimetric chemsensor aiming at detecting Cr 3+ has been synthesized, and it is based on the “Off-On” effect of a rhodamine derivative. Comparing with other metal irons (Na +, K +, Ni 2+, Hg 2+, Fe 3+, Mn 2+, Co 2+, Cd 2+, Cu 2+, Pb 2+, Zn 2+, Mg 2+, Ba 2+, Ag +, Fe 2+, Ce 3+), the chemsensor has a quick and accurate response to Cr 3+ in H 2O-EtOH solution (4/1, v/v). There is an obvious change in color, from colorless to bright pink when Cr 3+ is detected. According to the fitting curve based on Benesi-Hildebrand equation and working curve of absorption strength in UV-vis spectrum, the binding pattern of Cr 3+ and the rhodamine derivative follows a 1:1 stoichiometry. The chemsensor shows great potential in monitoring Cr 3+ in the aqueous medium with high efficiency, which is supposed to complete the recognition in the minimum as 5.2?×?10 ?7 mol/L within 5 min. 相似文献
6.
In this paper, carbon quantum dots (N-S-CDs) containing sulfur and nitrogen were synthesized using citric acid and thiourea. The average particle size of N-S-CDs is 8 nm. The N-S-CDs surface contains various of functional groups, which has good water solubility. The fluorescence quantum yield of N-S-CDs is as high as 36.8%. N-S-CDs emits strong blue fluorescence in aqueous solution and has good photostability in neutral and alkaline NaCl solution. N-S-CDs has unique selectivity and high sensitivity to Fe3+ and Hg2+ ions, and the lowest detection limits are 1.4 μM and 0.16 μM, respectively. Under the interference of other metal ions, Fe3+ and Hg2+ ions can still effectively and stably quench the fluorescence of N-S-CDs. In addition, in the detection of actual samples, N-S-CDs can effectively detect Fe3+ and Hg2+ ions in tap water and lake water. 相似文献
7.
Two novel macromolecules based on 2-[3-(2-aminoethylsulfanyl)propylsulfanyl]ethanamine covalently bound to one and two units of rhodamine-B moieties, 1 and 2, were prepared and utilized as fluoroionophores and chromophores for the optical detection of Hg 2+ ions. The sensors were readily prepared by a conventional two-step synthesis. Especially, sensor 1 exhibits high sensitivity and selective OFF–ON fluorescence enhancement and chromogenic change upon binding to Hg 2+, which served as a “naked-eye” indicator by a noticeable color change of the solution (from colorless to pink–red color). 1 is shown to discriminate various competing metal ions, particularly Ag + and Cu 2+, as well as Cd 2+, Na +, Li +, K +, Ba 2+, Co 2+, Ni 2+, Mg 2+, Mn 2+ and Al 3+, with a detection limit of 10 ppb. 相似文献
8.
A novel fluorescent rhodamine based chemosensor (E)-3′,6′-bis(diethylamino)-2-((2-(pyridin-2-ylmethoxy)benzylidene)amino)spiro[isoindoline-1,9′-xanthen]-3-one, RSP, had been successfully developed and well characterized by NMR, FT-IR and Mass spectroscopy. The chemosensor exhibits high selectivity for Hg 2+ over other ions (Ag +, Pb 2+, Cu 2+, Ni 2+, Fe 3+, Co 2+, Zn 2+ and Cd 2+) with fluorescence enhancement in ethanol solution. More over the detection limit of the sensor is in the 10 ?6 M level. The binding ratio of RSP-Hg 2+ complex was determined to be 1:1 according to the Job plot. Test strips based on RSP were fabricated, which showed the application of the sensor for detection of mercuric ions in water by naked eyes. 相似文献
9.
Based on resonance energy transfer (FRET) from dansyl to rhodamine 101, a new fluorescent probe (compound 1) containing rhodamine 101 and a dansyl unit was synthesized for detecting Hg 2+ through ratiometric sensing in DMSO aqueous solutions. This probe shows a fast, reversible and selective response toward Hg 2+ in a wide pH range. Hg 2+ induced ring-opening reactions of the spirolactam rhodamine moiety of 1, leading to the formation of fluorescent derivatives that can serve as the FRET acceptors. Very large stokes shift (220 nm) was observed in this case. About 97-fold increase in fluorescence intensity ratio was observed upon its binding with Hg 2+. 相似文献
10.
A 1,8-naphthalimide derivative with a reactive aliphatic hydroxyl was designed and synthesized as a fluorescent probe. Its structure was characterized by IR, 1H NMR, 13C NMR, LC-MS and HPLC. The probe showed high selectivity and sensitivity to Hg 2+ over other metal ions such as Pb 2+, Na +, K +, Cd 2+, Cr 3+, Zn 2+, Cu 2+, Ni 2+, Ca 2+, Fe 3+, Fe 2+, Co 2+, Mn 2+ and Mg 2+ in MeCN/H 2O (15/85, v/v). The increase in fluorescence intensity was linearly proportional to the concentration of Hg 2+ in the range of 18–40 μM with a detection limit of 1.38 × 10 ?7 mol/L. The probe could work in a pH span of 4.3–9.0 and respond to Hg 2+ quickly with strong anti-interference ability. Job’s plot suggested a 1:2 complex of the probe and Hg 2+. 相似文献
11.
In this study, bio-ultrasound-assisted synthesized gold nanoparticles using Gracilaria canaliculata algae have been immobilized on a polymeric support and used as a glassy probe chemosensor for detection and rapid removal of Hg 2+ ions. The function of the suggested chemosensor has been explained based on gold-amalgam formation and its catalytic role on the reaction of sodium borohydride and rhodamine B (RhB) with fluorescent and colorimetric sensing function. The catalyzed reduction of RhB by the gold amalgam led to a distinguished color change from red and yellow florescence to colorless by converting the amount of Hg 2+ deposited on Au-NPs. The detection limit of the colorimetric and fluorescence assays for Hg 2+ was 2.21 nM and 1.10 nM respectively. By exposing the mentioned colorless solution to air for at least 2 h, unexpectedly it was observed that the color and fluorescence of RhB were restored. Have the benefit of the above phenomenon a recyclable and portable glass-based sensor has been provided by immobilizing the Au-NPs and RB on the glass slide using electrospinning. Moreover, the introduced combinatorial membrane has facilitated the detection and removal of Hg 2+ ions in various Hg (II)-contaminated real water samples with efficiency of up to 99%. 相似文献
12.
Fluorescence probes serves as unique detection methods for its simplicity and low detection limit (LOD) and especially bioimaging ability. Research on the probes has already sprouted during the last decade with the help of its molecular recognition properties. This review spotlights recent progress in sensing and bioimaging biologically, environmentally and industrially important metal ions e.g. Zn 2+, Cu 2+, Hg 2+, Ag + etc. using suitable fluorescent chemosensors including carbon quantum dots (CQD). 相似文献
13.
A new rhodamine-based reversible chemosensor ( 2) was synthesized, which exhibits high sensitivity and selectivity for Cu 2+ but no significant response toward other competitive metal ions in aqueous solution. Upon the addition of Cu 2+, the spirolactam ring of 2 was opened and the solution color changed from colorless to red. Strangely, an unexpected fluorescence quenching was observed,
which is contrary to the fluorescence turn-on of the most rhodamine-based chemosensors. The likely novel sensing mechanism
has been proposed. 相似文献
14.
A new fluorescent chemosensor 2-(2-thiophene)imidazo [4,5,f]-1,10-phenanthroline ( L) was prepared and characterized. By adding univalent or divalent metal ions such as Na +, K +, Mg 2+, Ba 2+, Mn 2+, Fe 2+, Co 2+, Ni 2+, Cu 2+, Ag +, Zn 2+, Cd 2+ and Hg 2+ ions into the solution of L in DMF under buffered conditions with the working pH ranging from 7.0 to 8.0, we found that L could be used to detect K + ratiometricly and it could also be applied to sense Co 2+ with the phenomenon of fluorescence quenching of L. While the response behavior of L was not discernibly affected by other examined metal ions. 相似文献
15.
A series of three di-ionizable calix[4]arenes with two pendant dansyl (1-dimethylaminonaphthalene-5-sulfonyl) groups linked
to the lower rims was synthesized. Structures of the three ligands were identical except for the length of the spacers which
connected the two dansyl groups to the calix[4]arene scaffold. Following conversion of the ligands into their di-ionized di(tetramethylammonium)
salts, absorption and emission spectrophotometry were utilized to probe the influence of metal cation (Li +, Na +, K +, Rb +, Cs +, Mg 2+, Ca 2+, Sr 2+, Ba 2+, Ag +, Cd 2+, Co 2+, Fe 2+, Hg 2+, Mn 2+, Pb 2+, Zn 2+ and Fe 3+) complexation in acetonitrile. Upon complexation with these metal cations, emission spectra underwent marked red shifts and
quenching of the dansyl group fluorescence for the di-ionized ligand with the shortest spacer. A similar effect was noted
for the di-ionized ligand with an intermediate spacer for all of the metal ions, except Ba 2+. For the di-ionized ligand with the longest spacer, the metal cations showed different effects on the emission spectrum.
Li +, Mg 2+, Ca 2+ and Ba 2+ caused enhancement of emission intensity with a red shift. Other metal cations produce quenching with red shifts in the emission
spectra. Transition metal cations interacted strongly with all three di-ionized ligands. In particular, Fe 3+ and Hg 2+ caused greater than 99% quenching of the dansyl fluorescence in the di-ionized ligands. 相似文献
17.
A new pyrene derivative (chemosensor 1) containing a picolinohydrazide moiety exhibits high selectivity for Cu 2+ ion detection in mixed aqueous media (CH 3OH:H 2O = 7:3). Significant fluorescence enhancement was observed with chemosensor 1 in the presence of Cu 2+. However, the metal ions Ag +, Ca 2+, Cd 2+, Co 2+, Cu 2+, Fe 2+, Fe 3+, Hg 2+, K +, Mg 2+, Mn 2+, Ni 2+, Pb 2+, and Zn 2+ produced only minor changes in fluorescence for the system. The apparent association constant ( K
a) of Cu 2+ binding in chemosensor 1 was found to be 2.75*10 3 M −1. The maximum fluorescence enhancement caused by Cu 2+ binding in chemosensor 1 was observed over the pH range 5–8. Moreover, by means of fluorescence microscopy experiments, it is demonstrated that 1 can be used as a fluorescent probe for detecting Cu 2+ in living cells. 相似文献
18.
An bis(2-aminoethyl)-2-(9-fluorenyl)malonamide as fluorophore ligand was immobilized onto mesoporous silica type SBA-15 via post synthesis grafting. The obtained material was characterized by small and wide angle X-ray diffraction, N 2 adsorption–desorption, Fourier transform infrared spectroscopy, Raman spectroscopy and thermogravimetric analysis that indicate the successful immobilization of the ligand on the surface of mesoporous silica. The sensing ability of the obtained material was studied by addition of the cations Fe 3+, Mg 2+, Cr 3+, Co 2+, Ni 2+, Cu 2+, Hg 2+ and Zn 2+ to water suspensions of the assayed solid. Of all the cations tested addition of Fe 3+ ion to a suspension of this material resulted in the largest decrease in the fluorescence intensity. Turn-off photoluminescence of this material was remarkably observed for iron ions in comparing of the other cations. A good linearity between the fluorescence intensity of this material and the concentration of Fe 3+ ion is constructed, which enables it as a fluorescence chemosensor for detecting the Fe 3+ ion with a suitable detection limit of 1.35?×?10 ?5. It can be introduced as a novel fluorescent sensor in aqueous solution for a lot of practical applications in chemical, environmental and biological systems. 相似文献
19.
A chemosensor, 2,2′-(1,4-phenylenedivinylene)bis-8-acetoxyquinoline ( 1), its fluorescent sensing behavior toward representative alkali ions (Na +, K +), alkaline earth ions (Mg 2+, Ca 2+), and transition-metal ions (Ni 2+, Cu 2+, Zn 2+, Hg 2+, Pb 2+, Cd 2+) was intensively investigated. The compound ( 1) exhibited pronounced Hg 2+ selective on–off-type fluoroionophoric properties among the representative ions in DMF/ethanol (1:9, v/v) solution. Moreover, the highly Hg 2+-selective fluorescence quenching property in conjunction with a visible colorimetric change from colorless to light yellow can be observed, leading to potential fabrication of both “naked-eye” and fluorescent detection of Hg 2+. 相似文献
20.
A new pyrene-based chemosensor ( 1) exhibits excellent selectivity for Fe 3+ ions over a wide range of tested metal ions Ag +, Ca 2+, Cd 2+, Co 2+, Cu 2+, Fe 2+, Hg 2+, K +, Mg 2+, Mn 2+, Ni 2+, Pb 2+, and Zn 2+. The binding of Fe 3+ to chemosensor 1 produces an emission band at 507 nm due to the formation of a Py-Py* excimer that is induced by Fe 3+-binding. The binding ratio of 1-Fe 3+ was determined to be 1:1 from a Job plot. The association constant of 1-Fe 3+ complexes was found to be 1.27?×?10 4 M ?1 from a Benesi-Hildebrand plot. In addition, fluorescence microscopy experiments show that 1 can be used as a fluorescent probe for detecting Fe 3+ in living cells. 相似文献
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