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Journal of Fluorescence

Nurhayat Özbek, Hakan Alp, Gonca Çelik, Tuğba Ak, Osman Can Çağılcı, Nurettin Yaylı, Ümmühan Ocak, Miraç Ocak
A chalcone-based Schiff base (5), capable of detecting iron (III) in partially aqueous media, has been designed, then synthesized by the condensation of 3-formyl-2-hydroxyquinoline and acetophenone. To determine iron (III) ion, a simple spectrofluorimetric method was developed by using the synthesized Schiff base. The developed method was validated by analyzing the certified reference material (CRM-SA-C Sandy Soil C). During the process of the determination of iron in food samples, satisfactory accuracy was obtained for spinach and rocket...
December 2, 2016: Journal of Fluorescence
Xiao-Yu Wang, Cheng-Gang Niu, Li-Juan Guo, Liu-Yin Hu, Sheng-Quan Wu, Guang-Ming Zeng, Fei Li
This paper describes a label-free 17E DNAzyme-based time-gated fluorescence sensor for Pb(2+) detection by unmodified gold nanoparticles (GNPs) and a terbium ternary complex. The fluorophore that used in this paper is a terbium ternary complex. Its signal can be measured in a time-gated manner which could eliminate most of the unspecific fluorescent background. It is well known that unfolded single-stranded DNA (ssDNA) could be adsorbed on GNPs while double-stranded DNA could not. The cleavage of the substrate by the 17E DNAzyme in the presence of Pb(2+) causes the release of ssDNA from the 17E-17S duplex to be absorbed onto GNPs, preventing the aggregation of GNPs and then leading to a fluorescence decrease of terbium ternary complex...
December 1, 2016: Journal of Fluorescence
Shokoufeh Delkhahi, Mahdi Rahaie, Fereshteh Rahimi
MicroRNAs are small RNAs which regulate gene expression by translational repression or degradation of messenger RNAs. Regards to important role of these biomolecules in human disease progress, to produce sensitive, simple and cost-effective assays for microRNAs are in urgent demand. miR-137 in Alzheimer's patients has demonstrated its potential as non-invasive biomarkers in blood for Alzheimer's disease diagnosis and prognosis. This paper describes a novel, sensitive and specific microRNA assay based on Colorimetric detection of gold nanoparticles and hybridization chain reaction amplification (HCR)...
December 1, 2016: Journal of Fluorescence
Marek Pietrzak, Marek Józefowicz, Agnieszka Bajorek, Janina R Heldt
Newly synthesized, differently substituted chalcones (1,3-diaryl-2-propen-1-ones) have been studied using steady-state and time-resolved techniques combined with quantum-chemical modelling. To explore spectroscopic structure - property relationships the substituent (acceptor moiety) was chosen according to systematic variation in the Hammett parameter. It was shown that photophysical properties of the studied donor-acceptor (D-A) molecules can be predicted in terms of a simple model from the properties of individual chromophores (composite-model of decoupled moieties: donor (D) and acceptor (A))...
November 30, 2016: Journal of Fluorescence
Kun-Peng Wang, Zhi-Hui Jin, Hui-Shi Shang, Cheng-Dong Lv, Qi Zhang, Shaojin Chen, Zhi-Qiang Hu
A coumarin-appended rhodamine derivative was prepared by reacting rhodamine hydrazide and coumarin-3-carboxylic acid, which fluorescence sensing behavior toward Zn(2+) against other metal ions was investigated in CH3CN. Significantly, the rodamine-coumarin derivative exhibited highly selective and sensitive recognition toward Zn(2+) with a limit of detection (LOD) down to 10(-9) M. Upon addition of Zn(2+), remarkable fluorescent intensities enhanced and also clear color changed from colorless to pink. The Job's plot indicated the formation of 1:1 complex between the rhodamine-coumarin derivative and Zn(2+)...
November 29, 2016: Journal of Fluorescence
Shuo Chen, Yukun Wu, Shoucheng Hu, Yi Zhao, Daining Fang
A novel deep-blue emitter PhImPOTD based on phenathroimidazole was synthesized, which is incorporated by an electron-donating dibenzothiophene unit and electron-withdrawing phenanthroimidazole and diphenylphosphine oxide moieties. Furthermore, the weak π-π stacking and intermolecular aggregation render the photoluminescence quantum yield is as high as 0.34 in the solid state. Non-doped organic light emitting diodes (OLEDs) based on PhImPOTD emitter exhibits a low turn-on voltage of 3.6 V, a favorable efficiency of 1...
November 29, 2016: Journal of Fluorescence
Xiaoqing Xiong, Yanyan Xu, Laijiu Zheng, Jun Yan, Hongjuan Zhao, Juan Zhang, Yanfeng Sun
As one of the most important coumarin-like dyes, disperse fluorescent Yellow 82 exhibits exceptionally large two-photon effects. Here, it was firstly introduced into the supercritical CO2 dyeing polyester fabrics in this work. Results of the present work showed that the dyeing parameters such as the dyeing time, pressure and temperature had remarkable influences on the color strength of fabrics. The optimized dyeing condition in supercritical CO2 dyeing has been proposed that the dyeing time was 60 min; the pressure was 25 MPa and the temperature was 120 °C...
November 28, 2016: Journal of Fluorescence
Shohre Rouhani, Malihe Pishvaei
Nanocomposites with thermo and photo-switchable fluorescent properties were synthesized via mini-emulsion polymerization based on spiropyran and methyl methacrylate monomer. The photophysical behavior of fluorescence nanocomposites was investigated by fluorescence spectrophotometry in different temperature, UV-light and time of exposure. It was found that methyl methacrylate polymer is capable of acting as a protective layer and play a critical role in improving the photostability of colorants. The nanocomposites exhibited excellent fluorescent thermo-switching action with respect to the free spiro molecule...
November 26, 2016: Journal of Fluorescence
Rong-Liang Liang, Yun-Sen Yang, Jian-Wei Zhou, Tian-Cai Liu, Xu-Ping Xu, Qian-Ni Liang, Zhen-Hua Chen, Zhi-Ning Dong, Ying-Song Wu
In this paper, a novel time-resolved fluorescence immunoassay (TRFIA) is described that allows the simultaneous quantitative detection of hepatitis B virus surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in human serum to aid the diagnosis and monitoring of hepatitis B virus infection. The proposed method was developed based on a two-step sandwich immunoassay protocol in which monoclonal antibodies against HBsAg and HBeAg were co-coated in 96 microtitration wells, then tracer polyclonal antibodies against HBsAg labeled with samarium and tracer monoclonal antibodies against HBeAg labeled with europium chelates were used for detection...
November 22, 2016: Journal of Fluorescence
Soma Mukherjee, Shrabani Talukder
A new coumarin based chemosensor has been developed for selective fluorescent recognition of Cu(2+) in MeOH/H2O (4:1, v/v at pH = 7.2 aqueous solution) medium with 1:1 binding stoichiometry. The in-situ prepared Cu(2+) complex displays high selectivity towards CN(-) via Cu(2+) displacement approach with detection limit in the micro molar range. Moreover, in presence of Cu(2+), the receptor exhibits reversible emission change with EDTA and thus offers an interesting property of molecular 'IMPLICATION' logic gate with Cu(2+) and EDTA as chemical inputs...
November 22, 2016: Journal of Fluorescence
Derya Topkaya Taskiran, Gulsiye Ozturk Urut, Sevda Ayata, Serap Alp
4-(4'-acetyloxy-3'-methoxybenzylidene)-5-oxazolone fluorescent molecules bearing four different aryl groups attached to the 2-position of 5-oxazolone ring have been investigated by spectrophotometric and potentiometric techniques in solution media. The acidity constants (pKa) of the fluorescent molecules were precisely determined in acetone, acetonitrile, dimethylformamide and in 1:1 mixture of toluene-isopropanol. The studied derivatives were titrated with tetrabutylammonium hydroxide and non-aqueous perchloric acid by scanning the basic and acidic region of the pH scale...
November 19, 2016: Journal of Fluorescence
Mahmoud A Omar, Abdel-Maaboud I Mohamed, Sayed M Derayea, Mohamed A Hammad, Abobakr A Mohamed
A novel, sensitive and selective spectrofluorimetric method has been developed and validated for determination of silodosine (SLD) in its dosage form and human plasma. The method is based on nucleophilic substitution reaction of SLD with 5-(dimethylamino) naphthalene-1-sulfonyl chloride (dansyl chloride) in presence of 5.0 × 10(-4) M sodium carbonate (pH 10.50) to yield a highly fluorescent derivative that was measured at 435 nm after excitation at 347 nm. The different experimental parameters affecting the development and stability of the reaction product were carefully studied and optimized...
November 19, 2016: Journal of Fluorescence
Melek Pamuk Algi, Zahide Oztas, Seha Tirkeş, Atilla Cihaner, Fatih Algi
Two chemiluminescent compounds containing 2,5-di(thien-2-yl)pyrrole and pyridazine units, namely 5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (5) and 6-phenyl-5,7-di(thiophen-2-yl)-2,3-dihydro-1H-pyrrolo[3,4-d]pyridazine-1,4(6H)-dione (6), were successfully synthesized and electrochemically polymerized. The compounds have chemiluminescent properties and glow in the presence of hydrogen peroxide in basic medium. The intensity of the glow can be increased dramatically by using Fe(3+) ions, hemin (1...
November 18, 2016: Journal of Fluorescence
Lijun Xu, Yang Chen, Ruihua Zhang, Tian Gao, Yajie Zhang, Xiaoqiang Shen, Renjun Pei
A G-quadruplex-based fluorescent biosensor for highly sensitive detection of barium ion (Ba(2+)) was constructed for the first time. In the absence of Ba(2+), the G-quadruplex-specific fluorescence ligand N-methyl mesoporphyrin IX (NMM) remained weakly fluorescent when coexisted with a single-stranded G-quadruplex sequence AGRO100. Upon addition of Ba(2+), AGRO100 was folded into G-quadruplex structures with the aid of Ba(2+), which bound with NMM by stacking forces and significantly enhanced its fluorescence...
November 18, 2016: Journal of Fluorescence
Belgin Şahin, Sevinc Zehra Topal, Devrim Atilla
In this study, a series of novel silicon (IV) phthalocyanines conjugated axially with anti-inflammatory (sulindac) and triethylene glycol groups has been synthesized. Different synthetic strategies were attempted to obtain the targeted molecules in high yield. The compounds were fully characterized by using different analyses techniques. Our objectives were to generate a system with sulindac group which enhances the singlet oxygen generation and exhibits anti-cancer effect. Therefore, photophysical and photochemical properties of these compounds were investigated in different solvents...
November 17, 2016: Journal of Fluorescence
Anu Kundu, Jayaraman Pitchaimani, Vedichi Madhu, Pachagounder Sakthivel, Ramasamy Ganesamoorthy, Savarimuthu Philip Anthony
Bay functionalized perylene diimide substituted with pyridine isomers, (2-pyridine (2HMP-PDI), 3-pyridine (3-HMP-PDI) and 4-pyridine (4-HMP-PDI)) have been synthesized and explored for selective coloro/fluorimetric sensing of heavy transition metal ions. HMP-PDIs showed strong NIR absorption (760-765 nm) in DMF. The absorption and fluorescence of HMP-PDIs have been tuned by make use of pyridine isomers. Reddish-orange color was observed for 2-HMP-PDI (λmax = 437, 551, 765 nm) whereas 4-HMP-PDI exhibited light green (λmax = 432, 522, 765 nm)...
November 17, 2016: Journal of Fluorescence
Vinod K Kannaujiya, Rajeshwar P Sinha
The chemistry of thiol-chromophore linkage plays a central role in the nature of fluorescence of phycoerythrin (PE). Interaction of thiol and chromophore is crucial for the energy transfer, redox signal and inhibition of oxidative damage. In the present investigation the effects of ultraviolet-B radiation on an emission fluorescence intensity and wavelength shift in PE due to interaction between thiol and chromophore by remarkable strategy of detection technique was studied. Purification of PE was done by using a gel permeation and ion exchange chromatography that yielded a quite high purity index (6...
November 17, 2016: Journal of Fluorescence
Wei Yang, Chunlin Liu, Qingyun Gao, Jinya Du, Ping Shen, Changying Yang
Five derivatives of 2, 3, 3-trimethyl-3H-indolium containing different electron donor groups (H1 - H5) were synthesized for the determination of proteins. H3, a sensitive red-emitting fluorescent probe, was found for the discrimination of hydrophobic proteins from hydrophilic. The OFF - ON fluorescence switch of H3 was caused by the formation of twisted intramolecular charge-transfer (TICT) state when it combined with hydrophobic proteins in aqueous buffer. There was a good linear relationship between the emission intensity of H3 and the casein concentration (r = 0...
November 17, 2016: Journal of Fluorescence
Yasaman-Sadat Borghei, Morteza Hosseini, Mehdi Khoobi, Mohammad Reza Ganjali
This study was designed to develop a highly selective and sensitive method towards fluorimetric sensing of cysteine (Cys) in water and human serum by using copper nanocluster. The Cys-CuNCs were characterized by scanning electron microscopy (SEM), FTIR, fluorescence and UV-Vis analysis. Spectroscopic evidences showed different intensities that were attributed to the different size of Cys-CuNCs. Enhancement in fluorescence intensity of copper nanoclusters with an increase in concentration of cysteine may enable them to be good candidates in detection systems...
November 17, 2016: Journal of Fluorescence
LianQing Li, ZhiHong Liu
A novel rhodamine based fluorescent sensor, L, was developed and investigated as a colorimetric and fluorescent sensor for Fe(3+) in dimethyl sulfoxide. The compound L showed a good selectivity and sensitivity toward Fe(3+) in the presence of large excess of other competitive ions. L can be used as a colorimetric and fluorescent sensor for Iron recognition in potential.
November 17, 2016: Journal of Fluorescence
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