Co-reporter:Lingjie Hou, Jia Feng, Yubin Wang, Chuan Dong, Shaomin Shuang, Yu Wang
Sensors and Actuators B: Chemical 2017 Volume 247(Volume 247) pp:
Publication Date(Web):1 August 2017
DOI:10.1016/j.snb.2017.03.027
•A method using a single sensor for the detection of both Al3+ and Cu2+ ions in organo-aqueous solution is developed.•This probe function as a “turn on” probe for Cu2+ and Al3+ ions.•The practical applicability of this probe has been examined in living cells.An efficient fluorescein based probe (H2L) for the dual sensing of Al3+ and Cu2+ has been synthesized and characterized. H2L was highly selective toward these two ions with different fluorescence signals and binding modes in two different media. In EtOH-H2O (3:2, v/v; pH 4.0), H2L selectively binds Al3+ to form a 1:1 ligand/metal complex, giving rise to a visible pale pink-to-yellow color change and fluorescence enhancement at 440 nm, while in CH3CN-H2O (2:3, v/v; pH 7.2), H2L and Cu2+ form a 1:2 ratio complex, resulting in a color change from pink to orange-yellow and a significant fluorescence enhancement at 520 nm. The binding modes were confirmed by fluorescence, absorption, IR, ESI-MS and 1H NMR titrations. The detection limits were calculated to be 7.32 × 10−8 M and 1.47 × 10−8 M for Al3+ and Cu2+, respectively. Cell imaging studies demonstrate that this sensor is capable of sensing Al3+ and Cu2+ in living cells.Download high-res image (188KB)Download full-size image
Co-reporter:Lingjie Hou;Xiangyu Kong;Yishou Wang;Jianbin Chao;Chenzhong Li;Chuan Dong;Shaomin Shuang
Journal of Materials Chemistry B 2017 vol. 5(Issue 45) pp:8957-8966
Publication Date(Web):2017/11/22
DOI:10.1039/C7TB01596H
2-(1-Amino-2-anthraquinonyliminomethyl)phenol (L) was facilely prepared as a spectroscopic probe by one step condensation between 1,2-diaminoanthraquinone and salicylaldehyde. The complexation of Cu2+ ions with L through 1 : 1 chelation resulted in a rapid pink-to-blue color change and significant quenching of the fluorescence at 604 nm in 1 : 1 THF : Tris–HCl buffer. The subsequent addition of S2− to this solution regenerated the initial spectrum of L as a result of L being released from the L–Cu2+ complex through a displacement mechanism, which makes L a dual-channel sensor for the naked eye detection of Cu2+ and S2− ions. The system has high selectivity toward Cu2+ and S2− ions even in the presence of other commonly coexisting ions and the detection limits were found to be 8.95 × 10−8 M and 1.36 × 10−7 M, respectively. Applicability of L to detect Cu2+ ions and S2− ions in tap water has been demonstrated. Paper strips were fabricated for the detection of Cu2+ and S2− by the colorimetric method. Furthermore, L has been successfully applied for cell imaging studies.
Co-reporter:Liyuan Qin;Lingjie Hou;Jia Feng;Jianbin Chao;Wei Jun Jin
Analytical Methods (2009-Present) 2017 vol. 9(Issue 2) pp:259-266
Publication Date(Web):2017/01/05
DOI:10.1039/C6AY02544G
A new and simple julolidine based molecular receptor system L linked to 4-phenylsemicarbazide through an imine moiety has been synthesized and characterized. In HEPES-buffered MeOH–H2O (4 : 1, v/v, pH = 7.4) solution, L selectively binds Cu2+ to form a 1 : 1 ligand/metal complex, leading to a color change from green to yellow and significant fluorescence quenching at 540 nm. The in situ formed L–Cu2+ complex is further utilized to sense cyanide ions with high selectivity and fluorescence enhancement performance via metal displacement assay. The detection limit is 2.28 × 10−7 M and 1.33 × 10−8 M for Cu2+ and CN−, respectively. The sensor has been successfully applied to detect cyanide in water samples. The fluorescence imaging experiments in living cells were also demonstrated, which concludes that the sensor is capable of sensing Cu2+ and CN− in living cells.
Co-reporter:Zhen Ming Dong, Wei Wang, Li Yuan Qin, Jia Feng, Jia Na Wang, Yu Wang
Journal of Photochemistry and Photobiology A: Chemistry 2017 Volume 335() pp:1-9
Publication Date(Web):15 February 2017
DOI:10.1016/j.jphotochem.2016.11.014
•Novel chemosensor L was synthesized and characterized.•L exhibits a turn-on type fluorescence response toward Zn2+ in aqueous medium.•The L-Zn2+ ensemble selectively responded to PPi through fluorescence quenching.•L is capable of monitoring intracellular Zn2+ and PPi in real time.•The probe can be excited in visible light.A new fluorescent probe 4′-hydroxy-3′-((8-quinolineimino) methyl)-4-biphenylcarbonitrile (L) has been synthesized for the sequential detection of Zn2+ and PPi in aqueous ethanolic (3/2 v/v) HEPES buffer (pH 7.1). Addition of Zn2+ to the solution of L resulted in a red shift (Δλ = 18 nm) with a pronounced enhancement in the fluorescence intensity, while there was no enhancement in presence of other metal ions. The subsequent addition of PPi anion can switch off the fluorescence signal by bringing the Zn2+ ion out of the coordination cavity of the chemosensor L. No interference was observed from other anions, making the L–Zn2+ ensemble a highly sensitive and selective PPi probe. The detection limit is 5.31 × 10−8 M and 9.41 × 10−8 M for Zn2+ and PPi, respectively. The sensing process is reversible and the probe may be recycled for further use. Cell imaging studies demonstrate that this sensor is capable of sensing Zn2+ and PPi in living cells.
Co-reporter:Li Yuan Qin, Ling Jie Hou, Jia Feng, Jian Bin Chao, Yu Wang, Wei Jun Jin
Synthetic Metals 2016 Volume 221() pp:206-213
Publication Date(Web):November 2016
DOI:10.1016/j.synthmet.2016.09.005
•A new julolidine-based fluorescent chemosensor L was prepared.•L exhibits a turn-on type fluorescence response toward Al3+ in aqueous medium.•The detection limit was as low as nano-molar level.•The probe could respond to Al3+ in a reversible manner.•L was employed for imaging the Al3+ ion in living biological cells.A reversible fluorescent-colorimetric Schiff-base receptor (L) derived from julolidine and aminourea was developed for the selective sensing of Al3+ ions in buffered aqueous medium. Sensor L demonstrated the presence of Al3+ ions by both fluorescence enhancement and an instantaneous color change of solution from colorless to yellow. L forms complex with Al3+ in 1:1 ratio as supported by Job’s plot analysis and mass spectroscopic measurement. The sensitivity of the fluorescent based assay (4.67 nM) for Al3+ is far below the WHO acceptable limit (7.41 μM) in drinking water. Furthermore, L was employed for imaging the Al3+ ion in living biological cells.A reversible fluorescent-colorimetric Schiff base receptor derived from julolidine and aminourea (L) was developed for the selective sensing of Al3+ ions in buffered aqueous solution. The sensitivity of the fluorescent based assay (4.67 nM) for Al3+ is far below the limit recommended in the WHO guidelines for drinking water (7.41 μM). The probe is very effective for detection of intracellular Al3+ through fluorescence microscopic imaging.
Co-reporter:Fang Yu, Ling Jie Hou, Li Yuan Qin, Jian Bin Chao, Yu Wang, Wei Jun Jin
Journal of Photochemistry and Photobiology A: Chemistry 2016 Volume 315() pp:8-13
Publication Date(Web):15 January 2016
DOI:10.1016/j.jphotochem.2015.09.006
•A novel Schiff base fluorescent chemosensor HL was prepared.•Optical absorption and emission measurements were performed.•HL manifests selective signaling response to Al3+ in aqueous medium.•HL is sensitive to Al3+ with detection limit of 36.6 nM.•The application of HL for imaging of Al3+ in living cells was achieved.A new simple Schiff-base ligand 2-Hydroxy-1-naphthaldehyde-(2-pyridyl) hydrazone (HL) was synthesized and characterized as a fluorescent probe. In aqueous solution containing 10% ethanol (Hexamethylenetetramine-HCl buffer, pH5.3), HL selectively binds Al3+to form a 1:1 ligand/metal complex, resulting in a color change from colorless to yellow–green and a significant fluorescence enhancement at 454 nm. The addition of EDTA quenches fluorescence of the HL·Al3+ complex, indicating that HL serves as a reversible chemosensor for Al3+. Under the optimum conditions, the dynamic range of the system was found to be linear up to 4.0 × 10−6 M Al3+ ions with a limit of detection of 36.6 nM. The probe is very effective for detection of intracellular Al3+ through fluorescence microscopic imaging.
Co-reporter:Fang Yu;Liyuan Qin;Zhuobin Shang
Chemical Research in Chinese Universities 2015 Volume 31( Issue 6) pp:919-924
Publication Date(Web):2015 December
DOI:10.1007/s40242-015-5163-6
A simple assay for the detection of Fe3+ in water by means of fluorescence spectroscopy was developed based on a commercially available reagent, Azomethine-H(A-H), allowing sensing trace levels of Fe3+ with high selectivity over other cations. A significant fluorescence quenching of A-H at 424 nm was found after its binding with Fe3+ in 100% aqueous solution at pH=7.0, while other physiologically relevant metal ions posed little interference. The fluorescence responses can be well described by the modified Stern-Volmer equation. A good linear relationship(R2=0.9904) was observed up to 1.6×10–5 mol/L Fe3+ ions. The detection limit, calculated via the 3σ IUPAC(international union of pure and applied chemistry) criteria, was 1.95×10–7 mol/L. Moreover, the colorimetric and fluorescent response of A-H to Fe3+ can be conveniently detected by the naked eye, providing a facile method for visual detection of Fe3+. The proposed method was used to determine Fe3+ in water samples. Moreover, inverted fluorescence microscopy imaging using human umbilical vein endothelial cells shows that A-H can be used as an effective fluorescent probe for detecting Fe3+ in living cells.
Co-reporter:Zhuo Bin Shang;Ya Juan Wen;Xiao Qing Yan;Huan He Sun;Wei Jun Jin
Luminescence 2014 Volume 29( Issue 6) pp:598-602
Publication Date(Web):
DOI:10.1002/bio.2588
ABSTRACT
A new fluorescent probe, 4-N,N-di(2-hydroxyethyl)imino-7-nitrobenzo-2-oxa-1,3-diazole (HINBD) was synthesized in a single step with reasonably good yield. The water-soluble HINBD emits strongly in the visible region (λex = 479 nm, λem = 545 nm) and is stable over a wide range of pH values. It was found that vitamin B12 (VB12) had the ability to quench the fluorescence of HINBD, and the quenched fluorescence intensity was proportional to the concentration of VB12. A method for VB12 determination based on the quenching fluorescence of HINBD was thus established. Interference effects of various substances, including sugars, vitamins, amino acids, inorganic cations and some organic substances have been studied. Under optimal conditions, the linear range is 0.0–2.4 × 10–5 mol/L. The determination limit is 8.3 × 10–8 mol/L. The method was applied to measure VB12 in pharmaceutical preparations with satisfactory results. Copyright © 2013 John Wiley & Sons, Ltd.
Co-reporter:Yu Wang, LiLi Shi, HuanHe Sun Sun, ZhuoBin Shang, JianBin Chao, WeiJun Jin
Journal of Luminescence 2013 Volume 139() pp:16-21
Publication Date(Web):July 2013
DOI:10.1016/j.jlumin.2013.02.028
A new acridine fluoroionophore containing two iminodiacetic acid ligands, Acridinyl Tetra Acid (ATA), was synthesized. The fluorescence sensing behavior of ATA toward metal ions was investigated in buffered aqueous media. The presence of Cu2+ resulted in significant quenching of the fluorescence emission from ATA, while other metal ions posed little interferences, if any. The fluorescence response was concentration-dependent and can be well described by the modified Stern–Volmer equation. A good linear relationship (R2=0.9952) was observed up to 3.0×10−6 mol L−1 Cu2+ ions. The detection limit, calculated following the 3σ IUPAC criteria, was 1.24×10−7 mol L−1. The presence of Cu2+ induces the formation of a 1:1 ligand/metal complex at neutral pH.Highlights► A new acridine fluoroionophore was synthesized for detection of Cu2+ in water. ► Iminodiacetic acid moiety was chosen as the ionophore. ► The fluoroionophore exhibits great fluorescence quenching effect for Cu2+.
Co-reporter:Yu Wang, Huanhe Sun, Lingjie Hou, Zhuobin Shang, Zhenming Dong and Weijun Jin
Analytical Methods 2013 vol. 5(Issue 20) pp:5493-5500
Publication Date(Web):22 Jul 2013
DOI:10.1039/C3AY40977E
Based on the displacement strategy, a new and simple sulfide-selective chemosignaling system was devised using 1,4-dihydroxyanthraquinone (DHAQ)–Cu2+ ensemble. In aqueous solution containing 10% ethanol (HEPES buffer, pH7.4), DHAQ could give rise to a visible yellow-to-pink color change with the addition of Cu2+. The resulting pink solution changed to yellow upon subsequent addition of sulfide anion. Moreover, DHAQ displays an “ON–OFF–ON” mode fluorescence change with alternately added Cu2+ and S2−. Experimental results show a low interference response towards other common anions. The selective switch-on fluorescence response of the sensing ensemble to S2− makes it suitable for sensing of S2− in aqueous solution. The detection limit is 5.98 × 10−8 M.
Co-reporter:Y. Wang;T. T. Feng;L. L. Shi;F. Liu
Journal of Inclusion Phenomena and Macrocyclic Chemistry 2013 Volume 76( Issue 1-2) pp:151-158
Publication Date(Web):2013 June
DOI:10.1007/s10847-012-0184-y
In the presence of small amount of 1-iodo butane (IBu) (0.1 % (v/v)), Naproxen (Nap) displays strong room temperature phosphorescence (RTP) in β-cyclodextrin (β-CD) solution without deoxygenation because of the formation of ternary complex of β-CD, Nap, and IBu. The results indicate that β-CD shows good enantiodiscrimination for (R)-Nap and (S)-Nap. The RTP intensity of (R)-Nap is larger than that of (S)-Nap, the difference being 29.2 %. Both (R)-Nap and (S)-Nap exhibit single exponential phosphorescence decay with different lifetimes of 2.535 ± 0.056 and 1.798 ± 0.076 ms for (R)-Nap and for (S)-Nap, respectively. The corresponding association constants evaluated for (R)-Nap/β-CD/IBu and (S)-Nap/β-CD/IBu ternary complexes are (8.02 ± 0.15) × 103 and (2.50 ± 0.06) × 103 L mol−1, respectively. Thus, the observation of RTP differences between (R)-Nap and (S)-Nap can be attributed to their different ability to form complexes with chiral β-CD.
Co-reporter:Yu Wang, Lei Wang, Li Li Shi, Zhuo Bin Shang, Zhao Zhang, Wei Jun Jin
Talanta 2012 Volume 94() pp:172-177
Publication Date(Web):30 May 2012
DOI:10.1016/j.talanta.2012.03.013
1,8-Dihydroxyanthraquinone (DHAQ) can form an inclusion complex with β-cyclodextrin(β-CD) in aqueous media, which can be employed to solubilize and stabilize the DHAQ in water. With the assistance of ammonia, the supramolecular DHAQ–β-CD complex showed a selective chromogenic behavior toward Cu2+ ions by changing the color of the solution from citrus red to purple red, which could be easily observed with the naked eye. Moreover, fluorescence emission of the system was selectively quenched by Cu2+ ions. The fluorescence response was concentration-dependent and can be well described by the typical Stern–Volmer model. An easily applied method for Cu2+ determination in an aqueous medium was thus established. Under the optimum conditions, the method exhibits a dynamic response range for Cu2+ from 8.0 × 10−7 to 2.0 × 10−5 M, with a detection limit of 2.7 × 10−7 mol L−1.Highlights► A new approach for the determination of Cu2+ in aqueous solution is reported. ► 1,8-Dihydroxyanthraquinone was used as the probe with the assistance of ammonia. ► The sensor exhibits both color change and fluorescence quenching effect for Cu2+. ► The sensor was applied in the determination of Cu2+ in water and tea samples.
Co-reporter:Zhuo Bin Shang;Shuang Hu;Wei Jun Jin
Luminescence 2011 Volume 26( Issue 6) pp:585-591
Publication Date(Web):
DOI:10.1002/bio.1274
ABSTRACT
A facile method was developed for the preparation of water soluble β-Cyclodextrin (β-CD)-modified CdSe quantum dots (QDs) (β-CD-QDs) by directly replacing the oleic acid ligands on the QDs surface with β-CD in an alkaline aqueous solution. The as-prepared QDs show good stability in aqueous solution for several months. Oxoanions, including phosphoric acid ion, sulphite acid ion and carbonic acid ion, affect the fluorescence of β-CD-QDs. Among them, H2PO4– exhibited the largest quenching effect. For the polyprotic acids (HO)3AO, the effect of acidic anions on the fluorescence of β-CD-QDs was in the order: monoanion (HO)2AO2– > dianion (HO)AO32– >> trianion AO43–. After photoactivation for several days in the presence of anions at alkaline pH, the β-CD-QDs exhibited strong fluorescence emission. The effect of various heavy and transition metal ions on the fluorescence properties of the β-CD-QDs was investigated further. It was found that Ag+, Hg2+ and Co2+ have significant quenching effect on the fluorescence of the β-CD-QDs. The Stern–Volmer quenching constants increased in the order: Hg2+ < Co2+ <Ag+. The adsorption model of metal ions on β-CD-QDs was explored. Copyright © 2011 John Wiley & Sons, Ltd.
Co-reporter:Yu Wang, XueYan Hu, Lei Wang, ZhuoBin Shang, JianBin Chao, WeiJun Jin
Sensors and Actuators B: Chemical 2011 Volume 156(Issue 1) pp:126-131
Publication Date(Web):10 August 2011
DOI:10.1016/j.snb.2011.03.083
A new acridine fluoroionophore containing two diethanolamine ligands, 4,5-bis(N,N-di (2-hydroxyethyl)iminomethyl)acridine (BHIA), was designed and synthesized based on the fluorophore-spacer-receptor format. And its fluorescent sensing behavior towards metal ions was investigated in buffered aqueous media. The presence of Cd2+ induces the formation of a 1:1 ligand/metal complex at neutral pH, which exhibits enhanced emission at 454 nm. The fluorescence intensity is linear with the Cd2+ concentration in the range of 1.0 × 10−6 to 3.0 × 10−5 M (R = 0.9967). Experimental results show a low interference response towards other metal ions. The selective switch-on fluorescence response of BHIA to Cd2+ makes it suitable for sensing of Cd2+ in aqueous solution. The detection limit is 1.3 × 10−7 M. Moreover, the results indicated that BHIA was a reversible chemosensor for Cd2+, which makes it attractive for sensing applications.
Co-reporter:Yu Wang, Tingting Feng, Jianbin Chao, Liping Qin, Zhao Zhang, Weijun Jin
Journal of Photochemistry and Photobiology A: Chemistry 2010 Volume 212(Issue 1) pp:49-55
Publication Date(Web):30 April 2010
DOI:10.1016/j.jphotochem.2010.03.015
Strong room temperature phosphorescence (RTP) of camphorquinone (CQ) is synergistically induced by α-cyclodextrin (α-CD) and 1,2-dibromoethane (1,2-DBE) without removal of oxygen dissolved in the solution because of the formation of ternary complex of α-CD, CQ, and 1,2-DBE. Both (R)-CQ and (S)-CQ exhibit single exponential phosphorescence decay with lifetimes of (0.274 ± 0.014) and (0.639 ± 0.021) ms for (R)-CQ and (S)-CQ, respectively. The relatively large RTP lifetime difference observed for (R)-CQ and (S)-CQ enables easy spectroscopic discrimination between this pair of enantiomers. The apparent association constant of (S)-CQ/1,2-DBE/α-CD complex is larger than that of (R)-CQ/1,2-DBE/α-CD complex, implying that the former ternary complex should consist of an optimal arrangement of components. 1H NMR as well as 2D NMR spectroscopy has been used to study the inclusion complexation of α-cyclodextrin with CQ in order to understand the binding model.
Co-reporter:Shuang Hu, Hongsheng Mao, Yu Wang
Journal of Photochemistry and Photobiology A: Chemistry 2009 Volume 204(Issue 1) pp:1-6
Publication Date(Web):30 April 2009
DOI:10.1016/j.jphotochem.2009.02.004
Using sodium sulfite as an oxygen scavenger, meso-tetra (4-N,N,N-trimethylanilinium) porphyrin-Pd (Pd-TAPP) emits strong and stable room temperature phosphorescence (RTP) in sodium dodecyl sulfate (SDS) micellar solution. Heavy metal ions, including Fe2+, Co2+, Ni2+ and Cu2+, can efficiently quench the phosphorescence of Pd-TAPP. The Stern–Volmer constants increased in the order Fe2+ < Co2+ < Cu2+ < Ni2+, directly reflecting the relative sensitivity of the method for these ions. The detection limits calculated following the 3σ IUPAC criteria are: 2.3 × 10−7 mol/L for Cu2+, 3.4 × 10−7 mol/L for Co2+, 1.2 × 10−7 mol/L for Ni2+ and 2.1 × 10−6 mol/L for Fe2+. The addition of these ions also resulted in reduction of the lifetime (τ) of Pd-TAPP. The linear relationship between the concentration of Fe2+, Co2+, Ni2+ or Cu2+ ions and τ0/τ indicated the dynamic quenching mechanism.
Co-reporter:Zhuo Bin Shang, Yu Wang, Wei Jun Jin
Talanta 2009 Volume 78(Issue 2) pp:364-369
Publication Date(Web):30 April 2009
DOI:10.1016/j.talanta.2008.11.025
Water-soluble luminescent CdSe quantum dots surface-modified with triethanolamine (TEA–CdSe-QDs) were prepared with high stability. The fluorescence of the TEA–CdSe-QDs was greatly quenched only when Hg2+ and I− coexisted in the solution, whereas addition of either Hg2+ or I− individually has no noticeable effect on the fluorescence emission. Such a unique quenching effect could be used for reciprocal recognition of mercury (II) ions and/or iodide anions in aqueous solution with rather high selectivity and sensitivity. The detection limits of Hg2+ or I− ion were 1.9 × 10−7 mol L-1 or 2.8 × 10−7 mol L−1, respectively. The adequate experiments showed that iodine (I) anions could bridge between TEA–CdSe-QDs and Hg2+ to form a stable complex (QDs–I−–Hg2+) and the following effective electron transfer from the QDs to the Hg2+ could be responsible for the fluorescence quenching of QDs.
Co-reporter:Xiao Qing Yan;Zhuo Bin Shang;Zhao Zhang;Wei Jun Jin
Luminescence 2009 Volume 24( Issue 4) pp:255-259
Publication Date(Web):
DOI:10.1002/bio.1109
Abstract
The water-soluble luminescent CdSe quantum dots were prepared by ligand exchange with triethanolamine (TEA). Oxygen can reversibly enhance the fluorescence of the synthesized quantum dots (TEA-CdSe-QDs) in aqueous solution. Nitric oxide radical (NO) can react easily with dissolved oxygen in water and was found to have a significant quenching effect on the fluorescence of the TEA-CdSe-QDs. The fluorescence responses were concentration-dependent and can be well described by the typical Stern–Volmer equation. A good linear relationship (R2 = 0.9963) was observed over the range 5.92 × 10−7 to 1.85 × 10−5 mol/L nitric oxide. Above this concentration was a second linear region ranging from 2.12 × 10−5 to 1.12 × 10−4 mol/L NO with a gentler slope. The detection limit, calculated following the 3σ IUPAC criteria, was 3.02 × 10−7 mol/L. The interference effect of some common interferents such as nitrite (NO2−), nitrate (NO3−), glucose and l-ascorbic acid on the detection of NO was negligible for the proposed system, demonstrating the potential utility of this probe for the detection of NO in biological systems. The possible mechanism was also discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Co-reporter:Xiao Hua Zhang, Yu Wang, Wei Jun Jin
Analytica Chimica Acta 2008 Volume 622(1–2) pp:157-162
Publication Date(Web):1 August 2008
DOI:10.1016/j.aca.2008.05.047
In the presence of a small amount of 1,2-dibromopropane (1,2-DBP), 1,1′-binaphthol (BINOL) displays strong room temperature phosphorescence in γ-cyclodextrin (γ-CD) solution without deoxygenation. The phosphorescence intensity as well as the phosphorescence lifetime of (S)-BINOL is greater than that of (R)-BINOL, indicating a distinct chiral discrimination of γ-CD toward this pair of enantiomers. Both (R)-BINOL and (S)-BINOL exhibit a double exponential phosphorescence decay with lifetimes of 5.89 ms and 17.3 ms for (R)-BINOL and 7.58 ms and 23.6 ms for (S)-BINOL, respectively. The association constant obtained for (S)-BINOL/γ-CD/1,2-DBP ternary complex is larger than that for (R)-BINOL/γ-CD/1,2-DBP complex. Thus, the observation of RTP lifetime differences between (R)-BINOL and (S)-BINOL can be attributed to their different ability to form complexes with chiral γ-CD, which is further supported by an analysis of the proton NMR chemical shift differences between (R)-BINOL and (S)-BINOL.
Co-reporter:Guo Hua Shi, Zhuo Bin Shang, Yu Wang, Wei Jun Jin, Tian Cai Zhang
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 2008 Volume 70(Issue 2) pp:247-252
Publication Date(Web):July 2008
DOI:10.1016/j.saa.2007.07.054
CdSe quantum dots (QDs) were synthesized in oleic acid and octadecene medium under high-temperature and dispersed in chloroform. Nitroaromatic explosives and their relative compounds, 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), nitrobenzene (NB), 2,4-dinitrochlorobenzene (DNBCl) and p-nitrotoluene (NT) can obviously cause the fluorescence quenching of the synthesized QDs. Under the optimum conditions, a nonlinear response was observed over the concentration range of 10−8 to 10−5 M for them all. The modified Stern–Volmer quenching equations of ln I0/I versus C show a good linear relation in 10−5 M order of magnitude, and the detection limits approach 10−6 to 10−7 M.
Co-reporter:Zhen Ming Dong, Wei Wang, Yu Bin Wang, Jia Na Wang, Li Yuan Qin, Yu Wang
Inorganica Chimica Acta (1 May 2017) Volume 461() pp:
Publication Date(Web):1 May 2017
DOI:10.1016/j.ica.2017.02.004
•Novel colorimetric chemosensor HL was synthesized and characterized.•The CN−-induced color change of HL can be observed by the naked eye.•The sensor exhibits high selectivity and sensitivity for CN− ion.•The sensing process is reversible.•Real sample analysis were performed.A new and simple receptor HL derived from quinoline-2-carbaldehyde and 2,4-dinitrophenylhydrazine was synthesized and explored as a colorimetric sensor for cyanide ion in DMSO/H2O (7:3, v/v) medium. Addition of cyanide ion to HL resulted in a color change from yellow to wine red with a significant bathochromic shift (∼125 nm) in the absorption maxima, which makes naked eye detection possible. The experimental results reveal that the formation of anionic species from deprotonation of the hydrazone NH moiety by CN− is responsible for the spectral changes. The sensor exhibits high selectivity and sensitivity for CN− ion and the detection limit were found to be 0.37 × 10−6 M. Moreover, the HL–CN− complex was reversibly bound and HL could be recovered by treatment with Ag+ or Cu2+ and reused without loss of sensing ability. Finally, the use of a test strip of probe HL to detect cyanide was reported.A new and simple receptor HL derived from quinoline-2-carbaldehyde and 2,4-dinitrophenylhydrazine was explored as a reversible and selective colorimetric sensor for cyanide ion in semi-aqueous medium. The detection limit is 0.37 × 10−6 M. The use of a test strip of probe HL to detect cyanide was reported.
Co-reporter:
Analytical Methods (2009-Present) 2013 - vol. 5(Issue 20) pp:NaN5500-5500
Publication Date(Web):2013/07/22
DOI:10.1039/C3AY40977E
Based on the displacement strategy, a new and simple sulfide-selective chemosignaling system was devised using 1,4-dihydroxyanthraquinone (DHAQ)–Cu2+ ensemble. In aqueous solution containing 10% ethanol (HEPES buffer, pH7.4), DHAQ could give rise to a visible yellow-to-pink color change with the addition of Cu2+. The resulting pink solution changed to yellow upon subsequent addition of sulfide anion. Moreover, DHAQ displays an “ON–OFF–ON” mode fluorescence change with alternately added Cu2+ and S2−. Experimental results show a low interference response towards other common anions. The selective switch-on fluorescence response of the sensing ensemble to S2− makes it suitable for sensing of S2− in aqueous solution. The detection limit is 5.98 × 10−8 M.
![Nonacyclo[43.3.1.13,7.19,13.115,19.121,25.127,31.133,37.139,43]hexapentaconta-1(49),3,5,7(56),9,11,13(55),15,17,19(54),21,23,25(53),27,29,31(52),33,35,37(51),39,41,43(50),45,47-tetracosaene-5,11,17,23,29,35,41,47-octasulfonic acid, 49,50,51,52,53,54,55,56-octahydroxy-](/data/chemimg/103300/137407-62-6.png)
![Nonacyclo[43.3.1.13,7.19,13.115,19.121,25.127,31.133,37.139,43]hexapentaconta-1(49),3,5,7(56),9,11,13(55),15,17,19(54),21,23,25(53),27,29,31(52),33,35,37(51),39,41,43(50),45,47-tetracosaene-5,11,17,23,29,35,41,47-octasulfonic acid, 49,50,51,52,53,54,55,56-octahydroxy-](/data/chemimg/103300/137407-62-6_b.png)
![Heptacyclo[31.3.1.13,7.19,13.115,19.121,25.127,31]dotetraconta-1(37),3,5,7(42),9,11,13(41),15,17,19(40),21,23,25(39),27,29,31(38),33,35-octadecaene-5,11,17,23,29,35-hexasulfonic acid, 37,38,39,40,41,42-hexahydroxy-](/data/chemimg/103300/102088-39-1.png)
![Heptacyclo[31.3.1.13,7.19,13.115,19.121,25.127,31]dotetraconta-1(37),3,5,7(42),9,11,13(41),15,17,19(40),21,23,25(39),27,29,31(38),33,35-octadecaene-5,11,17,23,29,35-hexasulfonic acid, 37,38,39,40,41,42-hexahydroxy-](/data/chemimg/103300/102088-39-1_b.png)
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