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Öğe A novel amperometric H2O2 biosensor constructed by cress peroxidase entrapped on BiFeO3 nanoparticles(Elsevier Science Sa, 2021) Caglar, Bulent; Icer, Fatih; Ozdokur, Kemal Volkan; Caglar, Sema; Ozdemir, Agah Oktay; Guner, Eda Keles; Beser, Burcu MeryemHerein, we synthesized ferromagnetic BiFeO3 nanoparticles with sizes of 20-60 nm and rhombohedral distorted perovskite structure without any co-formed impurity phases by sol-gel method. Structural, morphological, magnetic, electronic and textural properties of BiFeO3 nanoparticles were characterized by using XRD, SEM-EDX, TEM, FTIR, XPS, VSM, UV-DRS, PL and BET techniques. The peroxidase was isolated from the Cress (Lepidium sativum) and purified by using precipitation of ammonium sulfate and chromatographic techniques; gel filtration and ion exchange chromatography which is showed wide range of thermal stability, maximum activity in the acidic environment and close to the body temperature. Afterwards, a novel amperometric biosensor based on Cress peroxidase entrapped on BiFeO3 nanoparticles modified carbon paste electrode was prepared for the first time to sensitive detection of H2O2. The prepared H2O2 biosensor was operated with the aid of chomamperometry technique by applying -0.8 V vs Ag/AgCl electrode. The developed biosensor exhibited a linear response towards to H2O2 in the concentration range of 2.0 10(-7) to 1.0 10(-5) M under the optimal conditions and limit of detection and quantification were estimated as 7.0 10(-8)M (2.7 mu g L-1) and 2.0 10(-7) M (8.7 mu g L-1), respectively. The repeatability of the electrode was calculated as 19.2 for 2.0 10(-7) M (N = 7) and the accuracy was 81.2% for this concentration. In addition, the H2O2 biosensor exhibited excellent stability up to ten days. Finally, the sensor developed was used for the analysis of H2O2 in milk samples and satisfactory recoveries were obtained under the operating conditions.Öğe Application of BiFeO3 and Au/BiFeO3 decorated kaolinite nanocomposites as efficient photocatalyst for degradation of dye and electrocatalyst for oxygen reduction reaction(Elsevier Science Sa, 2021) Caglar, Bulent; Guner, Eda Keles; Ozdokur, Kemal Volkan; Ozdemir, Agah Oktay; Icer, Fatih; Caglar, Sema; Dogan, BilgeTo improve the photocatalytic performance and solve the aggregation problem of BiFeO3 nanoparticles, kaolinite-BiFeO3 photocatalyst was successfully prepared for the first time by decoration of ferromagnetic BiFeO3 nanoparticles onto kaolinite surface. Comparative characteristics of kaolinite, bare BiFeO3 and kaolinite-BiFeO3 photocatalyst were investigated in detail by XRD, TEM, SEM-EDX, XPS, FTIR, VSM, UV-DRS, PL, zeta potential and BET techniques. The photocatalytic activities of the samples were also evaluated by photodegradation of rhodamine B as a model reaction under different irradiations like UVA, visible and sunlight. The kaolinite-BiFeO3 exhibited more superior photocatalytic activity as compared with other samples, which is best fitted to pseudofirst-order kinetic. The reactive species trapping experiments indicated that photogenerated-holes play major roles in the degradation process whereas superoxide radicals possess a secondary effect. Enhanced photocatalytic activity of kaolinite-BiFeO3 is attributed to its kaolinite platform that reduces the recombination opportunities of the photogenerated holes and electrons as well as increases the surface area, decreases the particle size and aggregation of nanoparticles. In addition, we also designed a novel electrocatalytic platform based on gold nanoparticles loaded on kaolinite-BiFeO3 modified carbon paste electrode surface for the examination of electrocatalytic activity for oxygen reduction reaction in alkaline medium. Electrochemical characterizations of the Au/BiFeO3/kaolinite modified carbon paste electrode and other bare surfaces were comparatively carried out with the aid of cyclic voltammetry, electrochemical impedance spectroscopy and chronoamperometry. Au/ BiFeO3/kaolinite modified carbon paste electrode exhibited 15-fold current enhancement together with 100 mV anodic potential shift compared with bare carbon paste electrode.Öğe Binuclear silver(I) complexes with the non-steroidal anti-inflammatory drug tolfenamic acid: Synthesis, characterization, cytotoxic activity and evaluation of cellular mechanism of action(Pergamon-Elsevier Science Ltd, 2021) Harurluoglu, Betul; Altay, Ahmet; Caglar, Sema; Yeniceri, Esma Kubra Kagan; Caglar, Bulent; Sahin, Zarife SibelIn this study, two new binuclear silver(I)-tolfenamic acid complexes including picoline derivative ligands, [Ag-2(mu-tolf)(2)(2-pic)(2)] 1 and [Ag-2(mu-tolf)(2)(4-pic)(2)] 2, were synthesized and identified by elemental analysis, FT-IR, 1H NMR and thermal analysis techniques. The in vitro cytotoxicity of the complexes was investigated against human breast cancer cell lines by XTT, flow cytometry, enzyme activity and western blot studies. The structures of 1 and 2 were clarified by single-crystal X-ray diffraction determination. The data clearly indicated that the Ag(I) ion is coordinated to one auxiliary ligand (2-pic or 4-pic), two tolfenamato ligands and another Ag(I) ion, demonstrating a distorted tetrahedral geometry. The tolfenamato ligands act as a bridging bidentate ligands. The chains are stabilized by intramolecular Ag(I)...pi and pi....pi interactions. The H-1 NMR and thermal analyses displayed the presence of picoline and tolfenamato ligands in the coordination sphere and the purity of the complexes. Both complexes exhibited potent cytotoxicity against cancer cell lines with higher selectivity than carboplatin. Flow cytometry and enzyme activity studies indicated that both complexes caused an increase in apoptosis, ROS and NO levels, cell cycle arrest, mitochondrial membrane damage and caspase activity, as well as inhibiting PI3K/Akt phosphorylation and modulating the oxidant/antioxidant balance system. Western blot analyses revealed the up-regulation of bax, caspase-3, caspase-9 and p53 proteins, but the down-regulation of bcl-2. These results demonstrate the vigorous apoptotic potential of the novel Ag(I) complexes in human breast cancer MDA-MB-453 cells. (C) 2021 Elsevier Ltd. All rights reserved.Öğe Characterization of a hybrid-smectite nanomaterial formed by immobilizing of N-pyridin-2-ylmethylsuccinamic acid onto (3-aminopropyl) triethoxysilane modified smectite and its potentiometric sensor application(Iop Publishing Ltd, 2016) Topcu, Cihan; Caglar, Sema; Caglar, Bulent; Coldur, Fatih; Cubuk, Osman; Sarp, Gokhan; Gedik, KubraA novel N-pyridin-2-ylmethylsuccinamic acid-functionalized smectite nanomaterial was synthesized by immobilizing of N-pyridin-2-ylmethylsuccinamic acid through chemical bonding onto (3-aminopropyl) triethoxysilane modified smectite. The structural, thermal, morphological and surface properties of raw, silane-grafted and the N-pyridin-2-ylmethylsuccinamic acid-functionalized smectites were investigated by various characterization techniques. The thermal analysis data showed the presence of peaks in the temperature range from 200 degrees C to 600 degrees C due to the presence of physically adsorbed silanes, intercalated silanes, surface grafted silanes and chemically grafted silane molecules between the smectite layers. The powder x-ray diffraction patterns clearly indicated that the aminopropyl molecules also intercalated into the smectite interlayers as bilayer arrangement whereas N-pyridin-2-ylmethylsuccinamic acid molecules were only attached to 3-aminopropyltriethoxysilane molecules on the external surface and edges of clay and they did not intercalate. Fourier transform infrared spectroscopy confirms N-pyridin-2-ylmethylsuccinamic acid molecules bonding through the amide bond between the amine group of aminopropyltriethoxysilane molecules and a carboxylic acid functional group of N-pyridin-2-ylmethylsuccinamic acid molecules. The guest molecules functionalized onto the smectite caused significant alterations in the textural and morphological parameters of the raw smectite.Öğe Fe3O4 nanoparticles decorated smectite nanocomposite: Characterization, photocatalytic and electrocatalytic activities(Elsevier Science Bv, 2018) Caglar, Bulent; Guner, Eda Keles; Keles, Kubra; Ozdokur, Kemal Volkan; Cubuk, Osman; Coldur, Fatih; Caglar, SemaMagnetite nanoparticles-decorated smectite nanocomposite was prepared by precipitation method and the obtained nanocomposite was used as both nanophotocatalyst for removal of rhodamine B from wastewater under UVA irradiation and electrocatalyst for the electrooxidation of chlorite ion on the carbon paste electrode. The raw smectite, bare magnetite and the synthesized nanocomposite catalyst were comparatively characterized by using XRD, FTIR, SEM, EDX, XPS, VSM, TG/DTG, DTA, DSC, electrophoretic mobility and BET techniques in detail. The XRD, SEM, electrophoretic mobility and VSM results indicated that the magnetite nanoparticles were uniformly distributed on the surface of smectite with a diameter of about 7 nm by electrostatic interactions and the prepared nanocomposite displayed well superparamagnetic behaviour with strong saturation magnetization at room temperature. The XPS, EDX, FTIR and thermal analysis data of synthesized nanocomposite further confirmed that the magnetite nanoparticles were successfully decorated on the smectite without formation of another ferric phase species. Furthermore, the surface area of magnetite smectite nanocomposite is higher than that of raw smectite, which is related to the magnetite nanoparticles decorated onto the smectite. The catalytic activities of all samples were comparatively investigated by using the degradation of aqueous rhodamine B solutions as a model pollutant in the heterogeneous photo-like-Fenton process which is well defined by the pseudo-first-order equation in kinetics. The resultant magnetite-smectite nanocomposite showed excellent magnetic separability and much better photocatalytic activity in a short period compared to the bare magnetite and smectite. The synergetic effect between magnetite and smectite showed high activity not only in photo-degradation but also in electrocatalytic applications. Because the developed nanocomposite material exhibited enhanced catalytic activity towards to chlorite ion oxidation it was applied for the voltammetric quantification of chlorite ion in aqueous medium. After the optimization of the measurement parameters, the limit of detection and quantification of the method were calculated as 3.0 and 10.0 mu M, respectively.Öğe Mono and dinuclear copper(II) naproxenato complexes containing 3-picoline and 4-picoline: synthesis, structure, properties, catechol oxidase, and antimicrobial activities(Taylor & Francis Ltd, 2014) Caglar, Sema; Adiguzel, Ekrem; Sariboga, Bahtiyar; Temel, Ersin; Buyukgungor, OrhanMononuclear and dinuclear copper(II) complexes [Cu-2(mu-nap)(4)(3-pic)(2)] (1) and [Cu(nap)(2)(H2O)(4-pic)(2)] (2) have been synthesized in the presence of 3-picoline and 4-picoline. Two complexes were characterized by FT-IR, UV-vis spectroscopic methods and their thermal stabilities were determined by TG/DTA/DTG techniques. The crystal structures of 1 and 2 were established by X-ray analysis. X-ray structure analysis has shown that copper(II) has a distorted square-pyramidal geometry. Naproxenate is a bridging ligand in 1 and monodentate in 2. Two complexes have shown catalytic activity on oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone exhibiting saturation kinetics at high substrate concentrations. The complexes were also screened for antimicrobial activity against pathogenic bacteria and fungi. The complexes exhibited antimicrobial activity against Entrococcus faecalis and Candida albicans.Öğe New metal complexes with diclofenac containing 2-pyridineethanol or 2-pyridinepropanol: synthesis, structural, spectroscopic, thermal properties, catechol oxidase and carbonic anhydrase activities(Taylor & Francis Ltd, 2016) Caglar, Sema; Dilek, Esra; Caglar, Bulent; Adiguzel, Ekrem; Temel, Ersin; Buyukgungor, Orhan; Tabak, AhmetFour new neutral diclofenac-based complexes, [Co(dicl)2(2-pyet)2] 1, [Ni(dicl)2(2-pyet)2] 2, [Cu2(dicl)2(2-pyet)2] 3, and [Cu2(dicl)2(2-pypr)2] 4 have been synthesized and characterized by elemental analysis, FT-IR, thermal analysis. Complexes 1, 3, and 4 have also been characterized by X-ray single-crystal structural analysis. The compounds of Co(II) and Ni(II) have octahedral geometry with two diclofenac and two 2-pyridineethanol ligands in the coordination sphere. The compounds of Cu(II) have square-pyramidal geometry and Cu(II) ions are linked via oxygens to the bridging 2-pyridineethanol or 2-pyridinepropanol ligands. The values acquired by FT-IR are in agreement with the single XRD data. Studies on the thermal properties are reported and the complexes are stable to 196, 216, 215, and 201 degrees C in air, respectively. Two dinuclear Cu(II) complexes have demonstrated catalytic activity on oxidation of 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone showing saturation kinetics at high substrate concentrations. The diclofenac complexes are investigated as inhibitors of the human cytosolic isoforms hCA I and II. The complexes are good as hCA I inhibitors (Kis of 1.52-55.06M) but only moderately efficient as hCA II inhibitors (Kis of 0.23-5.61M). [GRAPHICS] .Öğe Novel silver(I) complexes bearing mefenamic acid and pyridine derivatives: Synthesis, chemical characterization and in vitro anticancer evaluation(Elsevier Science Sa, 2019) Altay, Ahmet; Caglar, Sema; Caglar, Bulent; Sahin, Zarife SibelTwo Ag(I) complexes [Ag-2(mu-mef)(2)(2-pymet)(2)]1, [Ag-2(mu-mef)(2)(2-Pyet)(2)](2) containing mefenamic acid, 2-pyridinemethanol and 2-pyridineethanol were synthesized and characterized by using SCXRD, FT-IR, elemental and thermal analysis techniques. The complex 1 was synthesized as a single crystal whereas the complex 2 was obtained as a microcrystalline powder. The complex 1 consists of binuclear structure. The argentophilic interaction occurs among silver(I) ions due to the short Ag center dot center dot center dot Ag distance (2.8710(10) angstrom). Two Ag(I) centers are connected by carboxylato oxygen-bridge to form the binuclear metal core. The FT-IR spectra and thermal analysis studies confirmed that both complexes exhibited similar structures. In vitro antiproliferative activity of both complexes were evaluated against MCF-7, HT-29 and HepG2 cancer cell lines. The apoptotic effects and intracellular ROS generation from both complexes were investigated in MCF-7 cell line by flow cytometry analysis. The XTT and LDH assays revealed that both complexes showed strong antiproliferative activity with higher selectivity towards cancer cells compared to the normal cells. In addition, Annexin V/propidium iodide assay exhibited that apoptotic cell number was increased in MCF-7 cells with increasing concentrations of Ag(I) complexes. Furthermore, both complexes induced the ROS generation considerably in MCF-7 cells suggesting the possible pro-oxidant activity of the novel synthesized Ag(I) complexes. Taken together, these findings provide a notable support for potential utility of Ag(I) complexes as novel anticancer agents against numerous kind of carcinogenesis.Öğe Structural characterization of chitosan-smectite nanocomposite and its application in the development of a novel potentiometric monohydrogen phosphate-selective sensor(Pergamon-Elsevier Science Ltd, 2018) Topcu, Cihan; Caglar, Bulent; Onder, Ahmet; Coldur, Fatih; Caglar, Sema; Guner, Eda Keles; Cubuk, OsmanChitosan-smectite biocomposite was prepared by intercalation of protonated chitosan molecules into the interlayer space of smectite in monolayer arrangement through cation exchange mechanism and the obtained biocomposite was successfully used as an electroactive component in the structure of a PVC membrane potentiometric sensor for the direct and highly selective determination of monohydrogen phosphate ions. The comparative elemental, structural, thermal and morphological analysis of starting-smectite, neat chitosan and chitosan-smectite were investigated by utilizing EDX, XRD, ATR-FTIR, TG/DTG/DTA, SEM and surface area measurement techniques. The optimum membrane composition, detection limit, response time, pH working range and repeatability of the proposed electrode were determined.Öğe Structural, thermal and morphological properties of a novel poly(acrylamide-co-methacrylic acid)/organoclay nanocomposite(Taylor & Francis Inc, 2017) Caglar, Bulent; Coldur, Fatih; Caglar, Sema; Cubuk, Osman; Tabak, Ahmet; Topcu, CihanA novel poly(acrylamide-co-methacrylic acid)/organoclay nanocomposite was prepared and its structural, thermal, and morphological properties were investigated by various techniques. The absence of diffraction peaks for the organomodified-smectite nanocomposite showed that dispersion of the clay nanolayers within the polymer matrix was in the form of an exfoliated nanostructure. Morphological studies confirmed that organomodified-clay dispersed homogeneously in the polymer matrix. Infrared spectroscopy results indicated that the organosmectite is physically dispersed in the polymer network without forming any chemical bonds. The thermal analysis data revealed that there are significant increases in temperatures of decomposition and softening points of polymer with addition of organoclay.Öğe Synthesis and characterization of four novel palladium(II) and platinum(II) complexes with 1-(2-aminoethyl)pyrrolidine, diclofenac and mefenamic acid: In vitro effect of these complexes on human serum paraoxanase1 activity(Wiley, 2018) Dilek, Esra; Caglar, Sema; Erdogan, Kuebra; Caglar, Bulent; Sahin, OnurIn this study, the effects of four novel mononuclear palladium(II) and platinum(II) complexes on the activity of human serum paraoxanase1 were examined. First, four novel mononuclear palladium(II) and platinum(II) complexes were synthesized with a nitrogen donor ligand 1-(2-aminoethyl)pyrrolidine and nonsteroidal anti-inflammatory drugs diclofenac, mefenamic acid. These complexes were characterized by spectroscopic, thermal, and elemental analyses. The crystal structures of complex [Pd(2-amepyr)(2)](dicl)(2) 1 and [Pd(2-amepyr)(2)](mef)(2) 3 were determined by X-ray crystallography. Then, paraoxonase1 enzyme was purified from human serum. The effects of these complexes on enzyme were evaluated in vitro. The complexes consist of the cationic unit and the counterions. The diclofenac and mefenamic acid acted as a counterion in the complexes. It was observed that all the complexes were stable up to high temperatures. These complexes, even at low doses, inhibited the activity of the enzyme with different inhibition mechanisms.Öğe Synthesis, characterization, photoluminescent properties and antimicrobial activities of two novel polymeric silver(I) complexes with diclofenac(Elsevier, 2017) Alisir, Sevim Hamamci; Sariboga, Bahtiyar; Caglar, Sema; Buyukgungor, OrhanTwo novel silver(l) complexes with diclofenac, ({2-(2,6-dicholoroanilino)phenylacetic acid} = did) namely [Ag(dicl)](n) (1) and [Ag(dicl)(bipy)](n) (2) (bipy: 4,4'-bipyridine), have been synthesized and characterized by elemental analysis, IR spectroscopy, thermal analysis and single-crystal X-ray diffraction. X-ray crystallographic data of 1 revealed that did anion adopts a mu(3)-eta(1),eta(2) coordinated mode link three Ag atoms generate 1D infinite chain structure. In 2, did ligand plays crucial role to form double ladder chain structure, clamping two neighboring [Ag(mu-bipy)](infinity), chains by using carboxylate oxygen atoms (O1, O2). The most interesting structural feature of 2 is the presence of strong pi center dot center dot center dot pi interactions between aromatic phenyl rings of did placed in the adjacent 1D chains, leads to forming 2D slab structure. The coordination modes of did in the title complexes are supported by using IR spectroscopy. Thermal stabilities of 1 and 2 have been determined by TG/DTA/DTG techniques. The luminescent properties of complex 1 and 2 have been investigated in the solid state at room temperature. Furthermore, the title complexes have been tested for their in vitro antibacterial activities and are determined to be highly effective for antibacterial activity against Gram(+) and Gram(-) pathogenic bacteria cells. 1 and 2 showed activity on Fungi, as well. (C) 2016 Elsevier B.V. All rights reserved.Öğe Synthesis, crystal structure, spectroscopy, thermal properties and carbonic anhydrase activities of new metal(II) complexes with mefenamic acid and picoline derivatives(Taylor & Francis Ltd, 2017) Dilek, Esra; Caglar, Sema; Dogancay, Nesrin; Caglar, Bulent; Sahin, Onur; Tabak, AhmetThe mononuclear six metal(II) complexes ([Co(mef)(2)(3-pic)(2)(CH3OH)(2)] (1), [Ni(mef)(2)(3-pic)(2)(CH3OH)(2)] (2), [Cu(mef)(2)(3-pic)(2)] (3), [Co(mef)(2)(4-pic)(2)] (4), [Ni(mef)(2)(4-pic)(2)] (5), and [Cu(mef)(2)(4-pic)(2)] (6) with mefenamic acid and picoline ligands were synthesized, characterized, and their carbonic anhydrase inhibitory activities were evaluated. The six complexes were characterized by elemental analysis, FT-IR spectroscopy, and thermal analyses. The crystal structures of 1, 3, and 6 were determined by X-ray crystallography. The complexes have octahedral geometry. In 1, the mefenamato ligand behaved as monodentate whereas in 3 and 6, the mefenamato ligand acted as a bidentate ligand. Complexes 3 and 6 consist of the mefenamate and 4-picoline ligands. In 1, unlike the other complexes, methanol acted as a ligand and was involved in the coordination. Carbonic anhydrase I and II isoenzymes were purified from human erythrocytes. The in vitro effects of mefenamic acid, 3-picoline, 4-picoline, and the six metal(II) complexes on these isoenzymes were evaluated. [GRAPHICS]Öğe Synthesis, structural characterization and evaluation of anticancer activity of polymeric silver(I) complexes based on niflumic acid/naproxen and picoline derivatives(Taylor & Francis Ltd, 2022) Caglar, Sema; Altay, Ahmet; Harurluoglu, Betul; Yeniceri, Esma K. K.; Caglar, Bulent; Sahin, OnurTwo polymeric mixed-ligand silver(I) complexes, [Ag(mu-nif)(4-pic)](n) (1) and [Ag-4(mu-nap)(4)(2-pic)(2)](n) (2), where Hnif: niflumic acid, Hnap: naproxen, 4-pic: 4-picoline and 2-pic: 2-picoline, were synthesized and characterized by single-crystal X-ray diffraction, FT-IR and H-1 NMR spectroscopies, elemental and thermal analysis techniques. In 1, nif ligand behaves as a mu(3)-N,O,O' bridge connecting three silver(I) ions and each silver(I) ion exhibits a seesaw geometry. In 2, nap ligands act as a mu-carboxylato-(O,O') bridge between two silver(I) ions and mu(3)-carboxylato-(O,O,O') bridge linking three silver(I) ions. Each silver(I) ion occurs in trigonal geometry. To uncover the anticancer properties of the complexes, first, their cytotoxic abilities were tested against three cancer cell lines, HT-29 (human colorectal adenocarcinoma), A-549 (human lung carcinoma), and MDA-MB-453 (human breast adenocarcinoma), and normal 3T3-L1 (mouse fibroblast) cell line by XTT tests. Afterwards, the anticancer mechanism of the complexes was tried to be elucidated through the flow cytometry analyzes. XTT assay results showed that the complexes exhibited the highest cytotoxic activity and selectivity on HT-29 cells among all the cell lines. Flow cytometry analyses revealed that both complexes induced the apoptosis through the mitochondrial membrane depolarization and activation of the caspase cascade in HT-29 cells.Öğe Synthesis, structural, thermal elucidation and in vitro anticancer activity of novel silver(I) complexes with non-steroidal anti-inflammatory drugs diclofenac and mefenamic acid including picoline derivatives(Pergamon-Elsevier Science Ltd, 2018) Altay, Ahmet; Caglar, Sema; Caglar, Bulent; Sahin, OnurSix new Ag(I) coordination complexes, namely [Ag-4(mu-dicl)(4)(2-pic)(3)] 1, [Ag-2(mu-mef)(2)(2-pic)(2)] 2, [Ag-2(mu-dicl)(2)(3-pic)(2)] 3, [Ag-2(mu-mef)(2)(3-pic)(2)] 4, [Ag-2(mu-dicl)(2)(4-pic)(2)] 5 and [Ag-2(mu-mef)(2)(4-pic)(2)] 6, were synthesized and characterized by elemental analysis, FT-IR and thermal analysis techniques. The crystal structures of 1, 3, 4 and 5 were determined by X-ray diffraction analysis, whereas 2 and 6 were obtained as microcrystalline powders. X-ray diffraction analysis demonstrated that 1 occurs as a tetranuclear complex, while 3, 4 and 5 have binuclear structures. A short Ag center dot center dot center dot Ag distances of 2.8446 and 2.8823 angstrom for 1, 2.8409 angstrom for 3, 2.8942 angstrom for 4 and 2.8423 angstrom for 5 were found in the complexes, indicating that argentophilic interactions exist between the silver ions. In 1, the dicl ligands act as mu(3)-O,O',O' bridging ligands between three Ag(I) ions. In 3, 4 and 5, the dicl and mef ligands behave as bridging ligands and bind two Ag(I) ions together with the carboxylato oxygen atoms. The simultaneous TG/DTG and DTA techniques were applied to interpret the mass losses, decomposition temperatures and corresponding processes of the thermal behaviours of the complexes. The experimental and calculated mass losses of the proposed structures for complexes 2 and 6 are quite compatible with each other and these complexes have very similar FT-IR spectra to the other complexes, which reflect their same structural geometries and characteristics. The cytotoxic activities of the complexes (16) were tested against three different cancer cell lines, MCF-7, HT-29 and HepG2, and one normal cell line, 3 T3-L1. XTT assay results demonstrated that although all the silver(I) complexes showed good cytotoxic activity, depending on the cell types tested, the complexes with mefanamic acid (2, 4 and 6) were found to predominate over those with diclofenac (1, 3 and 5), as well as the superiority of 3-picoline to 4-picoline and 2-picoline. Moreover, compared with the cytotoxic potential of carboplatin, 4 especially exhibited a significant cancer cell inhibitory rate and lower cytotoxicity toward the normal cell line, with much higher selectivity indexes. (C) 2018 Elsevier Ltd. All rights reserved.Öğe Y Synthesis, characterization, and in vitro effect of the Cu(II) complex with niflumic acid and 3-picoline on paraoxanase-I(Wiley-V C H Verlag Gmbh, 2019) Dilek, Esra; Caglar, Sema; Cardak, Seda; Karakoc, Baris; Caglar, Bulent; Sahin, OnurNiflumic acid is used to treat inflammatory rheumatoid diseases, pain, and fever. The present study reports the experimental, spectroscopic, thermal, structural analyses, and biological activities of this complex. The nonsteroidal anti-inflammatory drug niflumic acid, 3-picoline, and copper(II) chloride were utilized to synthesize a new complex: [Cu2Cl2(nif)(2)(3-pic)(4)]. The crystal structure of [Cu2Cl2(nif)(2)(3-pic)(4)] was determined by X-ray crystallography. The complex crystallizes in the triclinic space group P-1 and each Cu(II) center displayed six-coordinated distorted octahedral geometry. Two Cu(II) centers are connected by a chloro-bridge to form the binuclear metal core. Finally, the in vitro effects of the synthesized new complex and free niflumic acid were evaluated on the human serum paraoxonase 1 enzyme. At low doses, both the new complex and free niflumic acid showed very good inhibition activity with different inhibition mechanisms. In addition, the results showed that the new complex has more inhibition activity than free niflumic acid.
