A novel optical chemical sensor for the determination of nickel(II) based on fluorescence quenching of newly synthesized thiazolo-triazol derivative and application to real samples

The characterization of a new optical sensor membrane is described for the determination of Ni(II) based on the immobilization of the fluorescent thiazolo-triazol derivative in PVC matrix. This optode has a wide linear range of 1.0 × 10 -9-4.4 × 10 -3 M at pH 6.0 for Ni(II) ions with the detection limit of 8.5 × 10 -10 M. The response of the optode membrane to Ni(II) is fully reversible and reveals a very good selectivity towards Ni(II) ion over a wide variety of other metal ions in solution. The membrane showed a good durability and short response time with no evidence of reagent leaching. The proposed optical sensor gives good results for applications in direct determination of Ni(II) in real samples that are satisfactorily comparable with corresponding data from flame atomic absorption spectrometry. © 2012 Elsevier B.V. All rights reserved

Selective optical sensing of copper(II) ions based on a novel cyclobutane-substituted Schiff base ligand embedded in polymer films

The paper reports on the spectral photophysical characteristics of a novel fluorescent Schiff base ligand 4-(1-phenyl-1-methylcyclobutyl-3-yl)-2-(2-hydroxy-1-naphtylidene) thiazole (LH) in solvents of ethanol (EtOH), tetrahydrofuran (THF), and chloroform (TCM) and in solid matrix of polyvinyl chloride (PVC). The LH dye embedded in plasticized PVC matrix has been used for preparing an optical sensor for Cu(II). The response of the sensor is based on the fluorescence quenching of LH by Cu(II) ions. At pH 6.0, the proposed sensor displays a calibration response for Cu(II) over a wide concentration range of 5.0 × 10-8 to 1.0 × 10-4 M. The sensor is fully reversible within the dynamic range and the response time ?90 is approximately 2.5 min under batch conditions. In addition to its high stability and reproducibility, the sensor shows a high selectivity towards Cu(II) ion with respect to common metal cations. The accuracy of the Cu(II) measurements using the proposed sensor was determined by analyzing standard reference materials of surface water and natural water. The sensor was also applied successfully for the determination of copper in green and black tea samples. © 2008 Elsevier B.V. All rights reserved.2003 Fen 005The work described in this paper was supported by the Research Founds of Ege University (Project no. 2003 Fen 005). Nur Aksuner received her BSc in chemistry and MSc in analytical chemistry from Ege University, Izmir, Turkey. She received PhD degree in chemistry at the same university in February 2008. Her current research interests include development of new optical sensors for metal ions. Emur Henden a BSc in chemistry from Ege University, Izmir, Turkey. He received his MSc and PhD in 1976 in chemistry at the University of Birmingham, UK. He is currently a professor of analytical chemistry at Ege University. His current research interests include the development of atomic spectrometric methods and optical sensors. Ibrahim Yilmaz a BSc in chemistry from Inonu University, MSc and PhD in chemistry from Firat University, Elazig, Turkey. He works as an associated professor in Firat University. His current research interests include synthesis of new thiazole and thiazole ring containing compounds, and substituted Schiff base ligands. Alaaddin Cukurovali a BSc in chemistry from Ankara University, MSc and PhD in chemistry from Firat University, Elazig, Turkey. He is currently a professor of chemistry at Firat University. His current research interests include synthesis and design of new heterocycles (thiazole and thiazole ring containing compounds, cyclobutane derivatives, azomethine and hydrazone compounds). -

A highly sensitive and selective fluorescent sensor for the determination of copper(II) based on a schiff base

A highly sensitive and selective optical sensor for the determination of trace amounts of Cu2+ based on fluorescence quenching has been developed. The sensing membrane was prepared by immobilization of a novel fluorescent Schiff base ligand 4-(1-phenyl-1-methylcyclobutane-3-yl)-2-(2-hydroxy-5-romobenzylidene)aminothiazole, on polyvinlyl chloride. The novel sensor, which has a linear range of 1.0 × 10-8 - 5.7 × 10-4 mol L-1 for Cu2+ ions with a detection limit of 8.8 × 10-9 mol L-1 (0.56 µg L-1), is fully reversible and the response time (?90) was approximately 2.5 min. The optode was highly selective and can readily be regenerated by treatment with 10-2 mol L-1 HCl. The accuracy of the proposed sensor was confirmed by analyzing standard reference materials of natural water and peach leaves. The sensor was successfully applied for the determination of copper in tap water and tea samples. © 2009 Elsevier Ltd. All rights reserved

Crystal structure of 4-(1-mesityl-1-methylcyclobutane-3-yl)-2-(N-ethyl)aminothiazole

WOS: 000176233200024PubMed: 12083567

Crystal structure of 4-(1-methyl-1-mesitylcyclobutane-3-yl)-2-aminothiazole

WOS: 000236113800016The crystal structure of 4-(1-methyl-1-mesityleyclobutane-3-yl)-2-aminothiazole (C17H22N2S1) has been determined by X-ray crystallographic techniques. The compound crystallizes in the triclinic space group P-1 with Z = 6. The crystal structure was solved by direct methods and refined by full-matrix least squares to a final R-value of 0.052 for 2298 observed reflections [I > 2 sigma (I)]. There are three crystallographically independent molecules, I, II and III. These molecules are held together by intermolecular N-H...N hydrogen bonds

Structure of 2-{2-[3-methyl-3-(2,4,6-trimethylphenyl)cyclobutyl]-2-oxoethyl}isoindole-1,3-dione

WOS: 0002243662000012-{2-[3-Methyl- 3-(2,4,6-trimethylphenyl) cyclobutyl]-2-oxoethyl} isoindole-1,3-dione (C-24 H25NO3) was synthesized, and its crystal structure was determined by X-ray crystallographic techniques. The compound crystallizes in the triclinic space group P-1, with unit cell parameters: a = 14.109(9) Angstrom, b = 14.130( 8) Angstrom, c = 12.152( 6) Angstrom, a = 105.62( 5)degrees, beta = 113.75( 4)degrees, gamma = 98.78(5)degrees, V = 2039.8(19) Angstrom(3), D-c = 1.223 g/cm(3), and Z = 4. The crystal structure has two crystallographically independent molecules, I and II. These molecules are held together by weak intermolecular C-H ... O interactions, forming a continuous chain. The dihedral angles between the N-substituted phthalimide moiety and cyclobutane ring in molecules I and II are 60.37(14) and 68.18(18)degrees, respectively