Salih Zeki Yıldız

Novel Functionalized Silica Gel for On-line Preconcentration of Cadmium(II), Copper(II), and Cobalt(II) with Determination by Flame Atomic Absorption Spectrometry

ABSTRACT Silica gel functionalized with 2-[N,N’-bis(2,3-dihydroxybenzaldimin)] aminoethylamine was employed as a novel sorbent for preconcentration of copper(II), cobalt(II), and cadmium(II) by flow injection-solid phase extraction. The pH of the analyte solution, sample and eluent flow rate, eluent volume, and the presence of concomitant ions were optimized. The limits of detection were 0.65, 0.52, and 1.42 µg/L and preconcentration factors were 12.3, 21.5, and 7.31 for cadmium(II), copper(II), and cobalt(II), respectively. The adsorption capacities of the functionalized silica gel for cadmium(II), copper(II), and cobalt(II) ions were 41.1, 31.7, and 26.5 mg/g. The preconcentration method was validated by determination of cadmium(II), copper(II), and cobalt(II) levels in Virginia Tobacco Leaves (CTA-VTL-2) and Water-Trace Elements (NWTM-15.2) certified reference materials. The method was also used to analyze water and food samples, and offers simplicity, reproducibility, high recovery, rapid and automated analysis, favorable ease of use, and low detection limits.

Enhanced Adsorption of Hexavalent Chromium Ions on Polyamine Polyurea Polymer: Isotherm, Kinetic, Thermodynamic Studies and Batch Processing Design

In the present study, polyamine polyurea polymer was employed for adsorption of Cr(VI) ions from aqueous solution. Adsorption studies were carried out to examine the effects of parameters such as pH, contact time, initial concentration of Cr(VI), and temperature. Optimum pH value and the contact time of the system were found to be 2.5 and 240 minutes, respectively. Thermodynamic parameters that calculated with the results of temperature studies showed the adsorption processes have exothermic, reversible, and spontaneous nature. The compared isotherm data clarified that Cr(VI) adsorption onto polyamine polyurea polymer (PPP) was proper with Langmuir isotherm with maximum adsorption capacity of 135.1 mg g−1. Pseudo-second-order kinetic model was found to be descriptive for the kinetic mechanism of Cr(VI) adsorption onto PPP. Single-stage batch adsorber was designed using equilibrium data for removal of Cr(VI) at various solutions. Consequently, the PPP has been found to be effective adsorbent for removal of Cr(VI) from water media. GRAPHICAL ABSTRACT

Synthesis, characterization, and determination of genotoxic effect of a novel dimeric 8-hydroxyquinoline Cd(II) SCN complex

Abstract In this study, a Cd(II) complex was synthesized using 8-hydroxyquinoline and thiocyanate as the ligands and structurally characterized with the combination of FTIR, 1H-NMR, 13C-NMR, UV–vis, and MS spectral data. Then, genotoxic effects of the prepared complex were investigated. Genotoxic properties of the dimeric 8-hydroxyquinolinthiocyanatoCd(II) [Cd2(8Q)2(SCN)2] complex synthesized as drug raw material were analyzed in human peripheral blood lymphocytes. Concentrations of 1, 2, 4, 6, and 8 μg/mL [Cd2(8Q)2(SCN)2] were used for 24 and 48  h durations. [Cd2(8Q)2(SCN)2] significantly increased chromosomal aberrations (CAs) at 4, 6, and 8 μg/mL concentrations after a 24- h period and 2 and 4 μg/mL after a 48-h period. [Cd2(8Q)2(SCN)2] significantly decreased the mitotic index (MI) at all concentrations, both at 24 and 48 h. Micronuclei frequency (MN) was not affected by [Cd2(8Q)2(SCN)2] treatment compared with the control. After application for a 48 h period, 6 and 8 μg/mL concentrations showed toxic effects both in chromosomal abnormality and in micronucleus tests. It also decreased the cytokinesis-block proliferation index (CBPI), but this result was statistically significant only at 6 and 8 μg/mL concentrations. In the comet assay (single-cell gel electrophoresis (SCGE)), significant increases in comet tail length, tail moment, and tail intensity were observed at all concentrations. [Cd2(8Q)2(SCN)2] displays clastogenic effect in the concentrations used in human peripheral lymphocytes at chromosomal abnormality, micronucleus tests, and cytokinesis-block proliferation index parameters. Further studies should be conducted in other test systems to evaluate the complete genotoxic potential of [Cd2(8Q)2(SCN)2].

Crystal structure of 4-(3,4-di­cyano­phen­oxy)-N-[3-(di­methyl­amino)­prop­yl]benzamide mono­hydrate: a phen­oxy­phthalo­nitrile derivative

In the title compound, the planes of the phenoxy and phthalonitrile rings are oriented at a dihedral angle of 60.39 (5)°. In the crystal, molecules are linked by O—H⋯O, O—H⋯N and N—H⋯O hydrogen bonds, forming slabs parallel to (100). The slabs are linked by a pair of inversion-related C—H⋯N hydrogen bonds, forming a three-dimensional structure.