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WOS: 000346275300019, In this study, one type of oak galls (galls of Quercus macrenthera, QMG) was used as tannin source for the production of tannic acid-based cryogels (CRGs). QMG-CRGs were characterized with scanning electron microscopy and attenuated total reflectance infrared. The produced CRGs have excellent characteristics such as extreme lightweightness. They look like sponges and are so elastic that they can easily absorb water and the water content can be removed easily by only compressing. These CRGs are able to swell violently immersed in aqueous solution. The prepared CRGs were used in removing uranyl ions from aqueous solutions. Some experimental parameters which affect the adsorption process as pH of the solution, initial uranyl concentration, and sorbent dosage have been investigated. The experimental data were analyzed by the Langmuir and Freundlich isotherm models and kinetic data were treated with pseudo first and second-order models. It is found that the adsorption data of uranium is equally well described by both Langmuir and Freundlich models, besides kinetic data strictly fits the pseudo-second-order rate model., Scientific Research Project Foundation of Cumhuriyet University, The laboratory equipment used in this study was taken from the budget of Scientific Research Project Foundation of Cumhuriyet University.

WOS: 000306252600012, In this study, the use of an extraordinary plant tissue, gall, has been studied for the removal of 2 differrent dyes. The adsorptions of basic blue (BB) and crystal violet (CV) were studied on raw Quercus macranthera galls (QMG). The effect of initial pH, contact time, initial dye concentration, and temperature was studied to explain batch adsorption process of the dyes on galls. Experimental data were assayed on pseudo-second order kinetic equations. The equilibrium process were well fitted with the Freundlich isotherm model for basic blue with the regression coefficients of 0.995, and the Langmuir isotherm for crystal violet with a regression coefficient of 0.993. The maximum adsorption capacities were 45.45 and 90.90 mg g(-1) for basic blue and crystal violet, respectively. The results show that QMG has a great potential as an effective low-cost sorbent for removal of dyes from aquatic media.

WOS: 000401097700012, PubMed ID: 28490150, In the present study, a novel and eco-friendly vortex-assisted ionic liquid-based microextraction method was developed for the determination of selenium in food. The microextraction method is based on the liberation of iodine in the presence of selenium; the liberated iodine reacts with I to form I-3. Anionic I-3 reacts with cationic crystal violet dye, and the product is extracted into 1-hexyl-3-methylimidazolium hexafluorophosphate phase in the presence of Triton X-114. The proposed method is linear in the range of 2.0-70 mu g L (1) and has a detection limit of 9.8 x 10 (2) mu g L (1). Relative standard deviations were 3.67% and 2.89% for the five replicate measurements of 14 and 35 mu g L (1) Se(IV), respectively. The proposed method was successfully applied to different food samples (NIST SRM 2976 mussel tissue, pepper, ginger, wheat flour, red lentil, traditional soup, cornflour, cornstarch, and garlic) after microwave digestion. (C) 2017 Elsevier Ltd. All rights reserved., Unit of the Scientific Research Projects of Cumhuriyet University; Cumhuriyet University Advanced Technology Research Center (CUTAM); Unit of Scientific Research Projects of Gaziosmanpasa University; Turkish Academy of Sciences, The authors are grateful for the financial support from the Unit of the Scientific Research Projects of Cumhuriyet University, Cumhuriyet University Advanced Technology Research Center (CUTAM) and the Unit of Scientific Research Projects of Gaziosmanpasa University. Dr. Mustafa Tuzen thank the Turkish Academy of Sciences for its financial support. The authors also thank Dr. Tulay Oymak for providing the standard reference material and for her help in microwave digestion experiments.

WOS: 000413177200002, PubMed ID: 28841406, The interactions of small molecules with G-quadruplex and double stranded DNA are important due to their potential biological and medical usages. In the present paper, the interactions of indium (III) phthalocyanines (quaternized 2,3,9,10,16,17,23,24-octakis-[(3-pyridyloxy) phthalocyaninato] chloroindium(III): OInPc and quaternized 2(3),9(10),16(17),23(24)-tetrakis-[(3-pyridyloxy) phthalocyaninato] chloroindium(III): TInPc) with hybrid G-quadruplex (Tel 21) and parallel G-quadruplexes (nucleolin, KRAS, c-MYC, vegf) were studied. The interactions of these phthalocyanines with ctDNA were also investigated. These interactions were measured by different spectroscopic techniques such as UV-Vis, fluorescence and circular dichroism. The UV-Vis spectroscopic data treated with Benesi-Hildebrand equation and Benesi-Hildebrand constants (K-BH) were calculated. These constants were found higher for octa peripheral pyridyloxy substituted phthalocyanine, OInPc. Besides, UV-Vis analysis showed that the interaction of G-quadruplexes with tetra peripheral pyridyloxy substituted phthalocyanine derivative (TInPc) resulted in removal of central indium (III) atom from the cavity of phthalocyanine macrocycle. The UV-Vis melting studies as well as fluorescence replacement techniques were also employed for clarification of mechanism. The binding mode of molecules with ct DNA was also supported with viscosity measurements. From the results, the stabilization and destabilization of G-quadruplex depending on the concentration of the OInPc and TInPc showed that these two indium (III) phthalocyanines have the potential of both the elucidation role of G-quadruplexes in gene expression and the usage in cancer therapy., Cumhuriyet University; Cumhuriyet University Advanced Technology Research Center (CUTAM), The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University and Cumhuriyet University Advanced Technology Research Center (CUTAM).

WOS: 000435269400002, In the present study, crosslinked egg white is used as a low-cost biosorbent for removal of a toxic dye, indigo carmine. The biosorbent preparation is easy and only N, N'-methylenebisi(acrylamide) is added for crosslinking. The characterization of the prepared material is done with scanning electron microscopy and IR spectroscopy. The surface charge is determined with point of zero charge method. The prepared biosorbent is used for removal of indigo carmine. The experimental parameters i(e. g., pH of solution, initial dye concentration, time) are optimized to achieve quantitative removal. The biosorption data of indigo carmine on crosslinked egg white is fitted with the Langmuir model with a Qmax value of 67.56mg g(-1). The kinetic data are treated with pseudo-first-and second-order models. The second-order model best explains the kinetic behavior of the process. The quantitative extraction of indigo carmine is achieved for 25 mgg(-1) of IC within 30 min at pH 2. The crosslinked egg white can be used several times after regeneration., Unit of the Scientific Research Projects of Cumhuriyet University; Cumhuriyet University Advanced Technology Research Center (CUTAM), The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University and Cumhuriyet University Advanced Technology Research Center (CUTAM).

WOS: 000406147600020, PubMed ID: 28321470, In the present study, a simple, mono step deep eutectic solvent (DES) extraction was developed for selective extraction of copper from sediment samples. The optimization of all experimental parameters, e.g. DES type, sample/DES ratio, contact time and temperature were performed with using BCR-280 R (lake sediment certified reference material). The limit of detection (LOD) and the limit of quantification (LOQ) were found as 1.2 and 3.97 A mu g L-1, respectively. The RSD of the procedure was 7.5%. The proposed extraction method was applied to river and lake sediments sampled from Serpincik, Celtek, KA +/- zA +/- lA +/- rmak (Fadl and Tecer region of the river), Sivas-Turkey., Unit of the Scientific Research Projects of Cumhuriyet University; Sakarya University; Gaziosmanpasa University; Erciyes University; Cumhuriyet University Advanced Technology Research Center (CUTAM), The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University, Sakarya University, Gaziosmanpasa University and Erciyes University and Cumhuriyet University Advanced Technology Research Center (CUTAM).

39th Colloquium on Spectroscopicum Internationale (CSI) -- AUG 30-SEP 03, 2015 -- New Univ Lisbon, Figueira da Foz, PORTUGAL, WOS: 000389093000026, PubMed ID: 26803444, In the present study a novel water soluble double-decker phthalocyanine was synthesized and calf thymus DNA interaction of the synthesized double-decker phthalocyanine was investigated. 5-(3-pyridyl)-1,3,4-oxadiazole substituted phthalonitrile 1 was prepared by a nucleophilic displacement reaction of 4-nitrophthalonitrile with 5-(3-pyridyl)-1,3,4-oxadiazole-2-thiol. Lutetium(III) double-decker phthalocyanine 2 was prepared by cyclotetramerization of compound 1. Water soluble lutetium(III) double-decker phthalocyanine 3 was prepared with quaternarization of compound 2. The synthesized double-decker phthalocyanine and calf thymus DNA interaction was investigated with UV-vis titrimetric methods, gel electrophoresis, and viscosity measurements. The fluorometric ethidium bromide replacement assay was conducted to clarify the binding mode of water soluble double-decker phthalocyanine. The thermodynamic parameters for interaction, K, Delta G(0), Delta H-0 and Delta S-0 were calculated between the temperature ranges of 25 degrees C-75 degrees C. To the best of our knowledge, this is the first study about a double-decker phthalocyanine and DNA interaction. (C) 2016 Published by Elsevier B.V., Univ Coimbra

WOS: 000385901800082, In the present study, interaction of a double-decker phthalocyanine with two G-quadruplex DNA, Tel 21 and cMYC, was investigated. To the best of our knowledge, this is the first study about G-quadruplex-double decker phthalocyanine interaction. The spectrophotometric titration method was used for binding constant calculations. From the binding constants, it can be said that double-decker phthalocyanine more likely to bind Tel 21 rather than cMYC. The conformational changes upon binding were monitored via circular dichroism spectroscopy. The ethidium bromide replacement assay was investigated spectrofluorometrically. (C) 2016 Published by Elsevier B.V., Cumhuriyet University Scientific Research Foundation Council (CUBAP) [ECZ-014], This work was supported by the Cumhuriyet University Scientific Research Foundation Council (CUBAP), Project Number: ECZ-014.

WOS: 000404310100002, PubMed ID: 28412579, Removal of toxic chemicals from environmental samples with low-cost methods and materials are very useful approach for especially large-scale applications. Green algae are highly abundant biomaterials which are employed as useful biosorbents in many studies. In the present study, an interesting type of green algae, Cladophora hutchinsiae (C. hutchinsiae) was used for removal of highly toxic chemical such as uranium. The pH, biosorbent concentration, contact time and temperature were optimized as 5.0, 12 g/L, 60 min and 20 degrees C, respectively. For the equilibrium calculations, three well known isotherm models (Langmuir, Freundlich and Dubinin-Radushkevich) were employed. The maximum biosorption capacity of the biosorbent was calculated as about 152 mg/g under the optimum batch conditions. The mean energy of biosorption was calculated as 8.39 kJ/mol from the D-R biosorption isotherm. The thermodynamic and kinetic characteristics of biosorption were also investigated to explain the nature of the process. The kinetic data best fits the pseudo-second-order kinetic model with a regression coefficient of > 0.99 for all studied temperatures. The calculated Delta H degrees and Delta G degrees values showed that the biosorption process is exothermic and spontaneous for temperatures between 293 and 333 K. Furthermore, after seven cycling process, the sorption and desorption efficiencies of the biosorbent were found to be 70, and 58%, respectively meaning that the biosorbent had sufficiently high reusability performance as a cleanup tool. (C) 2017 Elsevier Ltd. All rights reserved., Cumhuriyet University; Gaziosmanpasa University; Karadeniz Technical University; Turkish Academy of Sciences, The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University, Gaziosmanpasa University and Karadeniz Technical University. Dr. Mustafa Tuzen also thanks to Turkish Academy of Sciences for financial support.

WOS: 000332034400084, A cloud point extraction (CPE) procedure was presented for the preconcentration of UO22+ ion in different water samples. Tetracycline (TC) is the second most widely used antibiotics in the world and is used as chelating agent. To the best of our knowledge, this is the first work that an antibiotic is used as a chelating agent for CPE of UO22+. Besides, the use of TC as complexing agent provides excellent chelating features. TC molecule has large numbers of functional groups (adjacent hydroxyl oxygen atoms and cyclohexanone oxygen atoms, amide groups) which can form stable complex with UO22+. After complexation with TC, UO22+ ions were quantitatively recovered in Triton X-100 after cooling in the ice bath. 3.0 mL of acetate buffer was added to the surfactant-rich phase prior to its analysis by UV-Vis spectrophotometer. The influence of analytical parameters including pH, buffer volume, TC, Triton X-100 concentrations, bath temperature, incubation time were optimized. The effect of the matrix ions on the recovery of UO22+ ions was investigated. The limit of detection was 0.0746 mu g mL(-1) along with enrichment factor of 14.3 with a R. S. D. of 3.6 %. The proposed procedure was applied to the analysis of various environmental water samples. On the other hand, the electronic distribution of TC molecule is investigated with their frontier molecular orbital density distributions.

WOS: 000316645100012, PubMed ID: 23298591, The removal of tetracycline (TC) from aqueous environment by new type of sorbents, tannin based cryogels (TAB CRGs) and control cryogels (CRGs) was studied in a batch system. The experimental parameters that affect the sorption of TC were optimized to achieve maximum removal yield. Prepared cryogels were characterized by SEM imaging, IR spectroscopy (ATR). Produced TAB cryogels have thin polymeric walls and interconnected large pores. The TAB cryogels are elastic and sponge like; its water content can easily be removed by only compressed with hand. The TAB cryogels restore their original shape and size within seconds after soaked in water. On the other, elasticity of blank CRG is lower. The Freundlich and Langmuir adsorption isotherms were conducted to deduce the mechanism of the process. The kinetics of TC adsorption was moderately fast and almost reached equilibrium in 150 min and the results followed pseudo-second-order kinetic model. (c) 2012 Elsevier B.V. All rights reserved.

WOS: 000388629900036, A new versatile solid phase extraction and spectrophotometric determination of uranium (VI) was proposed with using poly(caprolactone-b-vinyl benzyl chloride-g-dimethyl amino ethyl methacrylate), poly(CL-b-VB-g-DMAEMA), amphiphilic brush type block/graft copolymer. The method is based on the adsorption of uranium(VI)-pyrocatechol violet complex on surface on the adsorbent. The parameters such as pH, amount of ligand and copolymer, sample volume were optimized. Detection limit, preconcentration factor and relative standard deviation were found as 0.45 A mu g L-1, 100 and 3.8 %, respectively. Adsorption capacity of the polymer for uranium(VI) was found 52 mg g(-1). The method was applied to different water samples and standard reference materials., Unit of the Scientific Research Projects of Cumhuriyet University; Gaziosmanpasa University; Bulent Ecevit University; Turkish Academy of Sciences, The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University, Gaziosmanpasa University and Bulent Ecevit University. Dr. Mustafa Tuzen thanks to Turkish Academy of Sciences for financial support.

WOS: 000356747300029, Compound 1 has been prepared by the reaction of 4-nitrophthalonitrile with triethanolamine. Compound 3 has been synthesized with quaternarization of compound 2 which prepared by cyclotetramerization of compound 1. The synthesized compounds have been characterized by elemental analysis, H-1 NMR, UV Vis, IR and MALDI-TOF MS spectral data. The interaction of compound 3 with calf thymus DNA was investigated spectrophotometrically. The phthalocyanine-DNA binding mechanism as well as the thermodynamic properties of binding was studied. The thermal denaturation profile, gel electrophoresis studies and the viscosity experiments were also conducted to clarify the mechanism. The replacement of ethidium bromide with phthalocyanine was monitored flourometrically to verify the binding mode. The Stern Volmer plot has nonlinear characteristic that implies both collisions of molecules and formation of ground state complexes which causes the fluorescence quenching. The experimental results indicate that the synthesized ball type water soluble phthalocyanine binds to calf thymus DNA via mainly intercalation. (C) 2015 Elsevier Ltd. All rights reserved.

WOS: 000362957900006, In the present study, spectrophotometric determination of uranyl with 2-(5-Bromo-2-pyridylazo)-5-(diethylamino) phenol after ionic liquid based microextraction has been developed. Effect of experimental parameters were optimized to achieve high sensitivity and stability of the complex. The analytical parameters such as linear range (1.33-670 mu g L-1), limit of detection (0.97 mu g L-1) and enrichment factor (150) were calculated for the method. The relative standard deviation of ten replicate measurement of uranyl was 6.53 and 2.59 % for 66 and 133 mu g L-1 uranium, respectively. The proposed method was used to determine the uranyl ions in spiked water samples., Cumhuriyet University; Gaziosmanpasa University; Turkish Academy of Sciences, The authors are fully grateful for the financial support of the Unit of the Scientific Research Projects of Cumhuriyet University and Gaziosmanpasa University. Dr. Mustafa Tuzen thanks to Turkish Academy of Sciences for financial support.

WOS: 000444821000006, In the present study, a macrofungus, Hypholoma fasciculare (H. fasciculare), was employed for the biosorption of vanadium from aqueous solutions. The characterization of H. fasciatlare was conducted using the FT-IR and SEM-EDS techniques before and after biosorption. The batch experimental parameters that affect the biosorption of vanadium on the macrofungus were optimized. The Langmuir, Freundlich, and D-R isotherms were employed, and it was found that the Langmuir and D-R models best explained the adsorption mechanism. The kinetic and thermodynamic characteristics of the biosorption mechanism were investigated in detail. The Langmuir biosorption capacity was found as 159.7 mg/g. The thermodynamic parameters showed that the biosorption of vanadium on the macrofungus was more feasible by decreasing the temperature and the exothermic character of Delta G degrees= -20.6 kJ/mol at 293 K and Delta G degrees= -19.9 kJ/mol at 323 K; Delta H degrees= -26.9 kJ/mol, Delta S degrees= -21.8 J/mol. K. The biosorption kinetics of vanadium onto the macrofungus H. lascictifare was best fitted with pseudo-second-order (R-2 >= 0.99). The desorption studies showed that 0.50 M of HNO3 effectively desorbs vanadium from H. fasciculare., King Fahd University of Petroleum and Minerals; Turkish Academy of Sciences, The authors would like to thank Dr. Ibrahim Turkekul for identification of the macrofungus. The authors give thanks to King Fahd University of Petroleum and Minerals for its support. Dr. Mustafa Tuzen thanks the Turkish Academy of Sciences for financial support.