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1.
Characterization of a highly Al3+‐selective fluorescence probe based on naphthalimide‐Schiff base and its application to practical water samples 下载免费PDF全文
Kesheng Shen Shanshan Mao Xinkui Shi Fei Wang Yuling Xu Stephen Opeyemi Aderinto Huilu Wu 《Luminescence》2018,33(1):54-63
A new fluorescent Al3+‐probe, N‐allyl‐4‐[3,3′‐((2‐aminoethyl)azanediyl)‐bis(N´‐(2‐hydroxybenzylidene)propanehy‐drazide)]‐1,8‐naphthalimide ( L ), was designed and synthesized based on 1,8‐naphthalimide. The probe L contains 1,8‐naphthalimide moiety as the fluorophore and a Schiff base as the recognition group. The structure of L was determined by single crystal X‐ray. L emission at 526 nm increased on addition of Al3+ under excitation wavelength at 350 nm. L exhibited high selectivity and sensitivity fluorescence emission towards to Al3+ in ethanol/Tris–HCl buffer solution (1:1, v/v, pH = 7.2) as compared with other tested metal ions. A good linearity with a correlation coefficient (R2) of 0.99 was observed in the concentration range 2–10 μM. The binding constant and the detection limit of L for Al3+ were calculated to 2.6 × 104 M?1 and 0.34 μM, respectively. The results of experiments that including Job plot, ultraviolet–visible (UV–Vis) light titration, fluorescence titration, ESI‐MS and 1H NMR titration, indicated a 1:1 stoichiometric complex between L and Al3+. L was highly effective in monitoring Al3+ in real‐life Yellow River and tap water samples. 相似文献
2.
A highly selective and sensitive turn‐on fluorescent probe for the detection of Al3+ and its bioimaging 下载免费PDF全文
Qingming Wang Lei Yang Hua Wang Jialiang Song Hui Ding Xin‐Hui Tang Hongmiao Yao 《Luminescence》2017,32(5):779-785
A novel fluorescent sensor, 1‐((2‐hydroxynaphthalen‐1‐yl)methylene)urea (ocn) has been designed and applied as a highly selective and sensitive fluorescent probe for recognition of Al3+ in Tris–HCl (pH = 7.20) solution. The probe ocn exhibits an excellent selectivity to Al3+ over other examined metal ions, anions and amino acids with a prominent fluorescence ‘turn‐on’ at 438 nm. ocn binds to Al3+ with a 2:1 binding stoichiometry and the detection limit was 0.3 μM. Furthermore, its capability of biological application was evaluated and the results showed that the sensor could be used to detect Al3+ in living cells. 相似文献
3.
Wen‐Jing Chen Sheng Zhang Wei‐Guang Zhang Jun Fan Xia Yin Sheng‐Run Zheng Wen‐Cui Su Zhi Zhang Tao Hong 《Chirality》2012,24(10):804-809
Quartz crystal microbalance (QCM) biosensor was used for the chiral recognition of five pairs of enantiomers by using goat serum albumin (GSA) and rabbit serum albumin (RbSA) as chiral selectors. Serum albumin (SA) was immobilized on the QCM through the self‐assembled monolayer technique, and the surface concentration of GSA and RbSA were 8.8 × 10?12 mol cm?2 and 1.2 × 10?11 mol cm?2, respectively. The QCM biosensors showed excellent sensitivity and selectivity. Meanwhile, the chiral recognition of SA sensors was quite species dependent. There were differences between GSA and RbSA sensors in the ability and the preference of chiral recognition. To R,S‐1,2,3,4‐tetrahydro‐1‐naphthylamine (R,S‐1‐TNA), R,S‐1‐(4‐methoxyphenyl)ethylamine (R,S‐4‐MPEA), and R,S‐1‐(3‐methoxyphenyl)ethylamine (R,S‐3‐MPEA), the preference of the stereoselective SA‐drug binding of the two kinds of SA sensors were consistent. However, to R,S‐2‐octanol (R, S‐2‐OT) and R,S‐methyl lactate (R,S‐MEL), the two kinds of SA sensors had opposite chiral recognition preference. Moreover, the interactions of SA and the five pairs of enantiomers have been further investigated through ultraviolet (UV) and fluorescent (FL) spectra. The UV/FL results were in accordance with the consequence of QCM. Chirality 24:804–809, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
4.
A colorimetric and fluorescent chemosensor for selective detection of Cu2+ based on a new diarylethene with a benzophenone hydrazone unit 下载免费PDF全文
A new photochromic diarylethene based on benzophenone hydrazone has been synthesized. Its photochromic and fluorescent properties changed upon alternating irradiation with UV /Vis light and adding Cu2+/EDTA in methanol, which showed that the diarylethene could be served as a colorimetric and fluorescent chemosensor for selective detection of Cu2+ based on internal charge transfer processes. The colorimetric and turn‐off fluorescent selective detection of Cu2+ was attributed to the 2:1 complex of the diarylethene and Cu2+. The binding constant (Ka ) was 1.53 × 104 L mol?1 and the limit of detection of the diarylethene for Cu2+ was calculated to be 1.45 × 10?6 mol L?1. In addition, the metal‐responsive photochromic behavior of diarylethene was applied successfully to the construction of a molecular logic circuit. 相似文献
5.
A highly sensitive and selective fluorescent probe for fluoride anions based on intramolecular charge transfer 下载免费PDF全文
Jingkai Liu Zhenghe Xu Caiyun Liu Lirong Xu Zhongpeng Wang Baocun Zhu 《Luminescence》2016,31(5):1166-1170
Currently, there is a great need to develop methods for the selective detection of fluoride anions (F–) owing to their toxicity in the environment and biological function in living systems. In this study, we developed a new fluorescent probe (probe 1) employing a Si–O bond as a highly selective recognition receptor for detecting F– via intramolecular charge transfer. Probe 1 could detect F– quantitatively using the turn‐on fluorescence spectroscopy method with excellent sensitivity in the range of 4–38 μM and a detection limit of 0.26 μM; the detection time was < 17 min. We anticipate that probe 1 would be used widely to monitor F– in the environment. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
6.
A series of novel, highly sensitive, and selective azo‐based anion sensors 1–3 have been designed and synthesized from the condensation reaction between 4‐amino azo benzene and three different aldehydes. The structure of the sensors 1–3 were confirmed by IR, HRMS, 1H NMR, and 13C NMR spectroscopic methods. Colorimetric naked‐eye analysis revealed the anion detection by receptors 2 and 3 as color changes from yellow to pink and yellow to orange, respectively. Anion sensing ability of all receptors was further investigated by 1H NMR titration, UV‐vis experiment, and fluorescence titration. UV‐vis measurements highly indicate the selective recognition of fluoride and acetate ions in 9:1 dimethyl sulfoxide–H2O (v/v) for receptors 2 and 3. Binding constant value showed among all receptors, receptor 3 has strong affinity toward F? and AcO? in semi‐aqueous medium, which is due to the presence of chromogenic signaling unit in it. The F? ion detection property of receptor 2 in organic medium was also extended in the real sample like toothpaste. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Two novel Rhodamine–pyrazolone‐based colorimetric off–on fluorescent chemosensors for Fe3+ ions were designed and synthesized using pyrazolone as the recognition moiety and Rhodamine 6G as the signalling moiety. The photophysical properties and Fe3+‐binding properties of sensors L1 and L2 in acetonitrile–aqueous solution were also investigated. Both sensors successfully exhibit a remarkably ‘turn‐on’ response, toward Fe3+, which was attributed to 1: 2 complex formation between Fe3+ and L1/L2. The fluorescent and colorimetric response to Fe3+ can be detected by the naked eye, which provides a facile method for the visual detection of Fe3+. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
A novel nickel(II) hexaaza macrocyclic complex, [Ni(LR,R)](ClO4)2 ( 1 ), containing chiral pendant groups was synthesized by an efficient one‐pot template condensation and characterized (LR,R═1,8‐di((R)‐α‐methylnaphthyl)‐1,3,6,8,10,13‐hexaazacyclotetradecane). The crystal structure of compound 1 was determined by single‐crystal X‐ray analysis. The complex was found to have a square‐planar coordination environment for the nickel(II) ion. Open framework [Ni(LR,R)]3[C6H3(COO)3]2 ( 2 ) was constructed from the self‐assembly of compound 1 with deprotonated 1,3,5‐benzenetricarboxylic acid, BTC3?. Chiral discrimination of rac‐1,1′‐bi‐2‐naphthol and rac‐2,2,2‐trifluoro‐1‐(9‐anthryl)ethanol was performed to determine the chiral recognition ability of the chiral complex ( 1 ) and its self‐assembled framework ( 2 ). Binaphthol showed a good chiral discrimination on the framework ( 2 ). The optimum experimental conditions for the chiral discrimination were examined by changing the weight ratio between the macrocyclic complex 1 or self‐assembled framework 2 and racemates. The detailed synthetic procedures, spectroscopic data including single‐crystal X‐ray analysis, and the results of the chiral recognition for the compounds are described. Chirality, 25:54‐58, 2013 © 2012 Wiley Periodicals, Inc. 相似文献
9.
A two‐channel flow‐injection (FI) method is reported for the determination of iodide and iodine by its enhancement effect on the Ru(bpy)33+–NADH chemiluminescence (CL) system. The limit of detection (3 s of blank) was 1.0 × 10–9 mol/L iodide/iodine, with a sample throughput of 60/h. The calibration graphs over the range 1.0–50 × 10–8 mol/L gave correlation coefficients of 0.9994 and 0.999 (n = 5) with relative standard deviations (RSD; n = 4) of 1.0–2.5%, respectively. The effects of interfering cations, anions and some organic compounds were also studied. The method was applied to iodized salts and pharmaceutical samples and the results obtained were in good agreement with the value quoted. The CL method developed was compared with spectrophotometric method. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
10.
Veneesha Thaver Mona‐Liza Lottering Dirk van Papendorp Annie Joubert 《Cell biochemistry and function》2009,27(4):205-210
The influence of 2‐methoxyestradiol (2‐ME) was investigated on cell numbers, morphology, cell cycle progression, and apoptosis induction in an oesophageal carcinoma cell line (WHCO3). Dose‐dependent studies (1 × 10?9M–1 × 10?6M) revealed that 2‐ME significantly reduced cell numbers to 60% in WHCO3 after 72 h of exposure at a concentration of 1 × 10?6M compared to vehicle‐treated cells. Morphological studies entailing light‐, fluorescent‐, as well as transmission electron microscopy (TEM) confirmed 2‐ME's antimitotic effects. These results indicated hallmarks of apoptosis including cell shrinkage, hypercondensation of chromatin, cell membrane blebbing, and apoptotic bodies in treated cells. Flow cytometric analyses demonstrated an increase in the G2/M‐phase after 2‐ME exposure; thus preventing cells from proceeding through the cell cycle. β‐tubulin immunofluorescence revealed that 2‐ME caused spindle disruption. In addition, increased expression of death receptor 5 protein was observed further supporting the proposed mechanism of apoptosis induction via the extrinsic pathway in 2‐ME‐exposed oesophageal carcinoma cells. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
11.
Two new phytotoxic γ‐lactones, pestalotines A and B ( 1 and 2 , resp.), along with 4‐oxo‐4H‐pyran‐3‐acetic acid ( 3 ) and 6‐hydroxyramulosin (=3,4,4a,5,6,7‐hexahydro‐6,8‐dihydroxy‐3‐methyl‐1H‐2‐benzopyran‐1‐one; 4 ), were isolateded from the culture of Pestalotiopsis sp. HC02, a fungus residing in the Chondracris rosee gut. Structures of the new metabolites were elucidated on the basis of their IR, NMR, and MS data. Pestalotines A and B ( 1 and 2 , resp.) significantly inhibited the radical growth of Echinochloa crusgalli with IC50 values of 1.85×10?4 and 2.50×10?4 M , respectively, comparable to that of 2‐(2,4‐dichlorophenoxy)acetic acid (0.94×10?4 M ) used as a positive control. 相似文献
12.
A N‐(2‐hydroxyethyl)piperazine dangled 2,5‐diphenyl‐1,3,4‐oxadiazole‐based fluorescent sensor for selective relay recognition of Cu2+ and sulfide in water 下载免费PDF全文
A new 2,5‐diphenyl‐1,3,4‐oxadiazole‐based derivative (L) was synthesized and applied as a highly selective and sensitive fluorescent sensor for relay recognition of Cu2+ and S2? in water (Tris–HCl 10 mM, pH = 7.0) solution. L exhibits an excellent selectivity to Cu2+ over other examined metal ions with a prominent fluorescence ‘turn‐off’ at 392 nm. L interacts with Cu2+ through a 1:2 binding stoichiometry with a detection limit of 4.8 × 10–7 M. The on‐site formed L–2Cu2+ complex exhibits excellent selectivity to S2? with a fluorescence ‘off–on’ response via a Cu2+ displacement approach. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
13.
Chemiluminescence detection of trace iodide with flow injection analysis of KMnO4‐carbon dots system
Ultra‐weak chemiluminescence (CL) from the reaction of iodide and KMnO4 was strongly enhanced by carbon nanodots (CNDs) in an acidic medium. The CL intensity was directly proportional to the concentration of iodide in the solution. Therefore, a flow‐injection CL system with high sensitivity, selectivity and reproducibility is proposed for the determination of iodide. The proposed method exhibited advantages over a linear range of 3.0 × 10?6–1.0 × 10?4 mol/L and had a detection limit of 3.5 × 10?7 mol/L. The method was successfully applied to the evaluation of iodide in food samples with recoveries of between 96 and 103%. The relative standard deviations were 2.1 and 4.1% for intra‐ and inter‐assay precision, respectively. 相似文献
14.
Aims: To evaluate individual and combined effects of temperature (4, 18 and 25°C), pH (7 and 10), ammonia (5 and 50 mg l?1) and exposure time (1, 2, 4 and 6 days) on the viability of Cryptosporidium parvum oocysts in water. Methods and Results: The viability of oocysts was evaluated using the fluorogenic vital dyes assay (4′,6‐diamidino‐2‐phenylindole and propidium iodide). All the factors analysed (temperature, pH, ammonia and exposure time) and their interaction were statistically significant (P < 0·005). Exposure of oocysts to pH 10 for 6 days at 25°C reduced oocyst viability from ~80% to 51%. Similarly, the exposure of C. parvum oocysts to 5 mg NH3 l?1 and 50 mg NH3 l?1 for 4 days reduced their viability from between ~80% to 41·5% and 14·8%, respectively. Conclusions: The interaction between pH, temperature and exposure time may have adverse effects on the survival of C. parvum oocysts in water. Low concentrations of ammonia, as commonly found in alga‐based wastewater systems, over a long period of time can produce high C. parvum oocyst inactivation rates. Significance and Impact of the Study: This study provides relevant data on the inactivation of C. parvum oocysts in alga‐based wastewater‐treatment systems in the northwest of Spain. 相似文献
15.
A simply synthesized biphenyl substituted piperidin‐4‐one for the fluorescence chemosensing of Cd2+ 下载免费PDF全文
Sumathi Poomalai Anju Kannan Padinjareveetil Sivaraj Ramasamy Tamil Selvan Govindaraj Mosae Selvakumar Paulraj Israel Vijayaraj Muthu Vijayan Enoch 《Luminescence》2017,32(8):1405-1410
Ion‐induced change in fluorescence is a straight‐forward method for detection of toxic metal ions showing immediate response. Cadmium ions are toxic to the environment. We report in this paper a piperidine‐4‐one‐based fluorescent chemosensor of Cd2+ ions, designed and synthesized by a simple method. The compound is characterized using infra‐red (IR) and 1H–NMR spectral techniques. The chemosensor showed Cd2+ ion selectivity and sensitivity in aqueous solution. The stoichiometry and the binding constants were determined using fluorescence spectroscopy. Piperidine‐4‐one shows a 1:1 stoichiometric binding to Cd2+. The limit of detection of Cd2+ was reported. 相似文献
16.
Koichi Natori Taizo Iwayama Osamu Yamabe Yuichi Kitamoto Hiroshi Ikeda Kenkichi Sakamoto Tetsutaro Hattori Sotaro Miyano 《Chirality》2015,27(8):479-486
Two analogs of blestriarene C (4,4'‐dimethoxy‐1,1'‐biphenanthrene‐2,2',7,7'‐tetraol) bearing no 7,7'‐dihydroxy ( 3 ) and 4,4'‐dimethoxy groups 4 were prepared. Unlike blestriarene C ( 1 ), compounds 3 and 4 , as well as 1,1'‐biphenanthrene‐2,2'‐diol ( 5 ), do not racemize under fluorescent lamp illumination. Cyclic voltammetry analysis reveals that compound 1 has a lower half‐wave potential (E1/2) than compounds 3 , 4 , 5 , suggesting that a redox cycle is involved in the racemization. Compound 1 racemizes by absorbing UV light corresponding to the 1Lb band. During the reaction, no side products are observed. The racemization is significantly inhibited under nitrogen. Based on these observations, we propose a feasible mechanism for the easy racemization of compound 1 , which is mediated by a cation radical generated in situ by a reversible photo‐induced oxygen oxidation. Chirality 27:479–486, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
17.
Detection of mercury(II) by DNA templated gold nanoclusters based on forming thymidine–Hg2+–thymidine duplexes 下载免费PDF全文
We have successfully synthesized gold nanoclusters (AuNCs) templated with DNA (5′‐CCCCCCCCCCCCTTTTTT‐3′), and subsequently employed the fluorescent DNA‐AuNCs as a novel probe for sensitive detections of mercury ions (Hg2+). Basically, the procedure is due to the formation of thymidine–Hg2+–thymidine duplexes between DNA‐AuNCs and Hg2+, thus leading to aggregations of DNA‐AuNCs described here occurring, and facilitating their fluorescence decrease. Significantly, this decrease of fluorescent signals permitted sensitive detection of Hg2+ in a linear range of 0.1–100 µmol L?1, with a detection limit of 0.083 µmol L?1 at a signal‐to‐noise ratio of 3. Additionally, the practicality of this probe for assaying Hg2+ in human urine and lake water samples was further validated, and showed various advantages including simplicity, selectivity, sensitivity and low cost, demonstrating its potential to broaden ways for assaying Hg2+ in real samples. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
18.
Daniel Gaughan Tica Pichulik Alasdair Leslie Ricardo A Fernandes Daniele Muraro Sarah Booth Kieran Zausmer Mei‐Yi Sun Benedikt Kessler Sarah Rowland‐Jones Vincenzo Cerundolo Alison Simmons 《The EMBO journal》2017,36(20):2998-3011
HIV‐1 traffics through dendritic cells (DCs) en route to establishing a productive infection in T lymphocytes but fails to induce an innate immune response. Within DC endosomes, HIV‐1 somehow evades detection by the pattern‐recognition receptor (PRR) Toll‐like receptor 8 (TLR8). Using a phosphoproteomic approach, we identified a robust and diverse signaling cascade triggered by HIV‐1 upon entry into human DCs. A secondary siRNA screen of the identified signaling factors revealed several new mediators of HIV‐1 trans‐infection of CD4+ T cells in DCs, including the dynein motor protein Snapin. Inhibition of Snapin enhanced localization of HIV‐1 with TLR8+ early endosomes, triggered a pro‐inflammatory response, and inhibited trans‐infection of CD4+ T cells. Snapin inhibited TLR8 signaling in the absence of HIV‐1 and is a general regulator of endosomal maturation. Thus, we identify a new mechanism of innate immune sensing by TLR8 in DCs, which is exploited by HIV‐1 to promote transmission. 相似文献
19.
Bovine serum albumin‐confined silver nanoclusters as fluorometric probe for detection of biothiols 下载免费PDF全文
Fluorescent bovine serum albumin‐confined silver nanoclusters (BSA–AgNCs) were demonstrated to be a novel and environmentally friendly probe for the rapid detection of biothiols such as cysteine (Cys), homocysteine (Hcy) and glutathione (GSH). The sensing was ascribed to the strong affinity between the mercapto group of the biothiols and the silver nanoclusters. The fluorescence intensity of BSA–AgNCs was quenched efficiently on increasing the concentration of biothiol, corresponding with a red‐shift in emission wavelength. However, the fluorescence of the silver nanoclusters was almost unchanged in the presence of other α‐amino acids at 10‐fold higher concentrations. By virtue of this specific response, a new, simple and rapid fluorescent method for detecting biothiols has been developed. The linear ranges for Cys, Hcy and GSH were 2.0 × 10‐6 to 9.0 × 10‐5 M (R2 = 0.994), 2.0 × 10‐6 to 1.2 × 10‐4 M (R2 = 0.996) and 1.0 × 10‐5 to 8.0 × 10‐5 M (R2 = 0.980), respectively. The detection limits were 8.1 × 10‐7 M for Cys, 1.0 × 10‐6 M for Hcy and 1.1 × 10‐6 M for GSH. Our proposed method was successfully applied to the determination of thiols in human plasma and the recovery was 94.83–105.24%. It is potentially applicable to protein‐stabilized silver nanoclusters in a chemical or biochemical sensing system. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
20.
Jingjing Yao Guangxu Xing Junling Han Yaning Sun Fangyu Wang Ruiguang Deng Xiaofei Hu Gaiping Zhang 《Journal of biophotonics》2017,10(5):657-663
Novel direct and indirect competitive fluorescence‐linked immunosorbent assays (c FLISA and ic FLISA) for detection of ochratoxin A (OTA) were described using CdTe quantum dots (QDs) as fluorescent label. CdTe QDs were successfully synthesized, which had an emission wavelength of 615 nm. The high purity monoclonal antibody against OTA was prepared through cell thawing and the octylic acid‐ammonium sulfate method. The OTA MAbs were successfully coupled with CdTe QDs, and which also retained the original biological activity. The 50% inhibition values (IC50) of the c FLISA and ic FLISA were 0.630 ng/mL, 0.234 ng/mL, the limits of detection (LOD) were 7.06 × 10–3 and 4.15 × 10–3 ng/mL, and detection ranges were 7.06 × 10–3 ? 18.34 ng/mL and 4.15 × 10–3 ? 4.88 ng/mL, in‐order. The recoveries were 96.0–104.7% along with coefficients of variation (CVs) below 10%. The FLISA provided novel method for determination of OTA and the potential of MAb–CdTe QDs for the establishment of fluorescent immunochromatographic test strip.