Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- 1 (98)
- 2 (82)
- Synthesis (60)
- Adsorption (52)
- Antimicrobial activity (47)
-
- 3 (44)
- Phthalocyanine (34)
- Antibacterial activity (29)
- Cytotoxicity (27)
- Molecular docking (26)
- Preconcentration (26)
- Palladium (25)
- Voltammetry (25)
- Cyclic voltammetry (24)
- Copper (23)
- Fluorescence (23)
- Schiff base (23)
- Lamiaceae (22)
- Spectrophotometry (22)
- Antioxidant activity (19)
- DFT (19)
- Kinetics (19)
- Chitosan (18)
- Nanoparticles (18)
- Cadmium (17)
- Antioxidant (16)
- Electrospinning (16)
- Photocatalysis (16)
- 4-triazole (15)
- Antimicrobial (15)
- Publication Year
Articles 751 - 780 of 2628
Full-Text Articles in Physical Sciences and Mathematics
Modeling And Optimizing Microwave-Assisted Extraction Of Antioxidant Compounds From Marigold Calendula Officinalis L. Using Response Surface Methodology, Burcu Bekdeşer
Turkish Journal of Chemistry
Calendula officinalis L. is a commercially important plant that finds application in the treatment of various diseases in traditional medicine. The total antioxidant capacity, radical scavenging activity, and total phenolic content of marigold extracts were investigated by Folin, CUPRAC, and DPPH assays, respectively. The optimum operating conditions of microwave-assisted extraction (MAE) including temperature, extraction time, solvent-to-solid ratio, and solvent concentration were ascertained by employing response surface methodology (RSM). The solvent (ethanol) concentration was the most significant operating factor among all responses of MAE. At the optimum extraction conditions, the maximum yield of total phenolic content, total antioxidant capacity, and radical …
Glucose Oxidase Immobilized Biofuel Cell Flow Channel Geometry Analysis By Cfd Simulations, Sali̇h Obut, Tahsi̇n Bahar
Glucose Oxidase Immobilized Biofuel Cell Flow Channel Geometry Analysis By Cfd Simulations, Sali̇h Obut, Tahsi̇n Bahar
Turkish Journal of Chemistry
Glucose oxidase was covalently immobilized to a porous electrode, which was developed by using ferrocene functionalized polyethyleneimine, multiwall carbon nanotubes, and carbon cloth for biofuel cell applications in our recent studies. The kinetics parameters (i.e. k$_{M}$, V$_{max})$ and other parameters required for the modeling study were determined experimentally. Fuel cell flow channel geometry was analyzed by a computational fluid dynamics modeling approach. Substrate flow rate and mass transfer for each proposed channel type were considered in the simulations. The results showed that serpentine type flow channels are advantageous over pin type or parallel flow channels to acquire sufficient performance from …
The Solvatochromism And Electronic Structure Of (E)-2-(2-Hydroxystyryl)Quinolin-8-Ol, Ayşegül Gümüş, Yadi̇gar Gülseven Sidir, İsa Sidir, Selçuk Gümüş
The Solvatochromism And Electronic Structure Of (E)-2-(2-Hydroxystyryl)Quinolin-8-Ol, Ayşegül Gümüş, Yadi̇gar Gülseven Sidir, İsa Sidir, Selçuk Gümüş
Turkish Journal of Chemistry
The (E)-2-(2-hydroxystyryl)quinolin-8-ol (abbreviated as HSQ) molecule was synthesized and characterized. The ESIPT, solvatochromism properties, electronic structure, and ground and excited electric dipole moments of this molecule were measured using absorption and fluorescence spectra recorded in 13 different solvents. Its electronic structure via electronic transitions was investigated to find the quantitative values of solvatochromism properties by LSER calculations. The ESIPT mechanism was clarified; ground and excited dipole moments were determined using solvatochromic shift methods. The DFT (B3LYP)/6-311$++$G(d,p) method and basis set with potential energy surface (PES) calculations of proton transfer were used to explain the ESIPT mechanism. NBO analysis, NLO properties, …
Investigation Of The Effects Of Some Water-Soluble Vitamins On Glutathione Reductase Enzyme Purified From Bovine Liver, Mehmet Riza Kivanç, Vedat Türkoğlu
Investigation Of The Effects Of Some Water-Soluble Vitamins On Glutathione Reductase Enzyme Purified From Bovine Liver, Mehmet Riza Kivanç, Vedat Türkoğlu
Turkish Journal of Chemistry
Glutathione reductase (GR, EC 1.8.1.7) is an antioxidant enzyme and is involved in the reducing reaction of oxidized glutathione. Glutathione and reduced glutathione are very crucial for micro- and macroorganisms because of their barrier function against radicals. Therefore, the aim of this article was to purify GR and evaluate the relationship between purified GR and vitamins. GR was purified from bovine liver using 2',5'-ADP Sepharose 4B column materials. To check the purity of each subunit of the enzyme, SDS-PAGE electrophoresis was performed and each one was 55 kDa. Afterwards, specific activity and purified ratio for the enzyme were calculated as …
Evaluation Of The Enrichment And Amplification Effect Of Pentachlorobenzene With Lower Bioconcentration In The Food Chain Before And After Modification, Ruihao Sun, Meijin Du, Yu Li
Evaluation Of The Enrichment And Amplification Effect Of Pentachlorobenzene With Lower Bioconcentration In The Food Chain Before And After Modification, Ruihao Sun, Meijin Du, Yu Li
Turkish Journal of Chemistry
In this paper, in order to construct a 3D quantitative structure--activity relationship (QSAR) model with the chlorobenzene (CB) molecular structure parameter as an independent variable and the octanol-water partition coefficient ($K_{OW})$ as a dependent variable, 9 kinds of CB molecules were used as training sets and 3 kinds of CB molecules were used as test sets. We adopted the QSAR module in the Sybyl-X2.0 software from the Tripos Corporation (USA). The molecular modification of the pentachlorobenzene molecule with low bioconcentration was carried out by combining a three-dimensional contour map and fractional factorial design. The results showed that the toxicity, migration, …
Design, Synthesis, And Antitumor Evaluation Of Novel Methylene Moiety-Tethered Tetrahydroquinoline Derivatives, Esaam Hamied Ahmed Hanashalshahaby, Canan Ünaleroğlu, Ayşe Ak Can, Alp Özgün, Bora Gari̇pcan
Design, Synthesis, And Antitumor Evaluation Of Novel Methylene Moiety-Tethered Tetrahydroquinoline Derivatives, Esaam Hamied Ahmed Hanashalshahaby, Canan Ünaleroğlu, Ayşe Ak Can, Alp Özgün, Bora Gari̇pcan
Turkish Journal of Chemistry
Novel methylene-tethered tetrahydroquinolines (THQs) and cyclopenta[$b$]pyridines were synthesized by one-pot multicomponent reactions of Mannich bases, enolizable ketones, and NH$_{4}$OAc in water by an environmentally friendly K-10 montmorillonite clay-catalyzed reaction. The cytotoxic activities of 1-(2-methyl-8-methylene-5,6,7,8-tetrahydroquinolin-3-yl)ethanone (9a), ethyl 2-methyl-8-methylene-5,6,7,8-tetrahydroquinoline-3 carboxylate (9b), and 1-(2-methyl-7-methylene-6,7-dihydro-5$H$-cyclopenta[$b$]pyridin-3-yl)ethanone (11a) were tested against rat glioblastoma (C6), human breast cancer (MCF-7), prostate cancer (PC3), neuroblastoma (SH-SY5Y), and mouse fibroblast (L929) cell lines in a concentration-dependent (50-300 μM) and time-dependent (24-72 h) manner and expressed as IC$_{50\, }$values. The results showed that compound 9a induced the lowest IC$_{50\, }$values in all cell lines ranging from 111 ± 1.1 μM to …
Stability Improvement By Crosslinking Of Previously Immobilized Glucose Oxidase On Carbon Nanotube-Based Bioanode, Tahsi̇n Bahar
Stability Improvement By Crosslinking Of Previously Immobilized Glucose Oxidase On Carbon Nanotube-Based Bioanode, Tahsi̇n Bahar
Turkish Journal of Chemistry
Bioanode stability with glucose oxidase was enhanced significantly by covalent crosslinking without substantial enzymatic activity and affinity loss. Initially, glucose oxidase was immobilized by aldehyde groups on the electrode that was developed using ferrocenecarboxaldehyde, polyethyleneimine, multiwall carbon nanotubes, and carbon cloth for biofuel cell applications. The glucose oxidase half-life was extended by more than 4 times, from 27.2 to 124.7 h, after the electrode was crosslinked. Enzymatic kinetic parameters were determined for the crosslinked enzyme and they were compared to the noncrosslinked immobilized enzyme parameters on the electrode. The apparent substrate affinity of the crosslinked enzyme electrode was decreased (i.e. …
One-Pot Synthesis Of Quinazolin-4(3$H$)-Ones And 2,3-Dihydroquinazolin-4(1$H$)-Ones Utilizing $N$-(2-Aminobenzoyl)Benzotriazoles, İlbi̇lge Merve Şenol, İlhami̇ Çeli̇k, İlker Avan
One-Pot Synthesis Of Quinazolin-4(3$H$)-Ones And 2,3-Dihydroquinazolin-4(1$H$)-Ones Utilizing $N$-(2-Aminobenzoyl)Benzotriazoles, İlbi̇lge Merve Şenol, İlhami̇ Çeli̇k, İlker Avan
Turkish Journal of Chemistry
A convenient and efficient method has emerged for the one-pot synthesis of substituted quinazolin-4(3$H)$-ones and nonaromatic alkaloids. 2-Substituted quinazolin-4(3H)-ones, 2,3-disubstituted quinazolin-4(3$H)$-ones, and 2,3-dihydroquinazolin-4(1$H)$-ones were obtained at yields of 46% to 95% by a one-pot reaction of $N$-(2-aminobenzoyl) benzotriazoles with amines and orthoesters or aldehydes under catalyst-free conditions.
Synthesis And Catalytic Activity Of Ionic Palladium \Textit{N}-Heterocyclic Carbene Complexes, Sedat Yaşar, Mi̇tat Akkoç, Namik Özdemi̇r, İsmai̇l Özdemi̇r
Synthesis And Catalytic Activity Of Ionic Palladium \Textit{N}-Heterocyclic Carbene Complexes, Sedat Yaşar, Mi̇tat Akkoç, Namik Özdemi̇r, İsmai̇l Özdemi̇r
Turkish Journal of Chemistry
The synthesis of 3 benzimidazole-based ionic Pd(II)-NHC complexes (NHC:$N$-heterocyclic carbene) is presented. The structures of the complexes are as follows: [NHC-PdBr$_{3}$]$^{-}$[NHC]$^{+}$. The ionic palladium(II)-NHC complexes were synthesized in high yields and were fully characterized by nuclear magnetic resonance spectroscopy, X-ray diffraction, LC-MS/MS, and elemental analysis. These complexes have been identified as active catalysts in Suzuki-Miyaura reactions in a solution of 2-propanol and water at room temperature for different aryl bromides.
Dispersive Liquid-Liquid Microextraction Of Parabens From Pharmaceuticals And Personal Care Products Prior To Their Determination Using Hplc-Dad, Malek Hassan, Usama Alshana, Nusret Ertaş
Dispersive Liquid-Liquid Microextraction Of Parabens From Pharmaceuticals And Personal Care Products Prior To Their Determination Using Hplc-Dad, Malek Hassan, Usama Alshana, Nusret Ertaş
Turkish Journal of Chemistry
Dispersive liquid--liquid microextraction followed by a back-extraction step was combined with HPLC-DAD for the determination of four parabens (i.e. methyl-, ethyl-, propyl-, and butylparaben). Optimum extraction conditions were found as follows: 225 $\mu $L of chloroform, 0.75 mL of ethanol, 7.5 mL of aqueous solution and within an extraction time of 15 s. Back-extraction into 100 $\mu $L of 50 mM sodium hydroxide solution within 20 s resulted in a reversed-phase HPLC-compatible extract. The analytes were separated at 20 $^{\circ}$C using methanol (A) and water (B), 40:60 (A:B, v/v) as the mobile phase, a flow rate of 1.0 mL min$^{-1}$ …
Synthesis, Characterization, And Investigation Of Singlet Oxygen, Dna Interaction, And Topoisomerase I Inhibition Properties Of Novel Zinc(Ii) Phthalocyanine, Ümi̇t Demi̇rbaş
Turkish Journal of Chemistry
In this work, phthalonitrile (3) and zinc(II) phthalocyanine (4) were prepared. To determine the photodynamic therapy potential of compound 4, singlet oxygen quantum yield, DNA binding and cleavage, and topoisomerase I inhibition experiments were performed. The singlet oxygen quantum yield value of compound 4 was found higher than that of the standard unsubstituted zinc(II) phthalocyanine compound (Std-ZnPc). The binding experiments showed that compound 4 interacted with ct-DNA strongly via nonintercalation mode. pBR322 plasmid DNA cleavage activity of the compound was investigated using agarose gel electrophoresis. The results showed that the compound 4 had important DNA cleavage activity. The E. coli …
Synthesis And Characterization Of Unsaturated Diacyl And Alkyl-Acyl Piperazine Derivatives, Sai̇t Sari, Seda Ünalan, Mehmet Yilmaz
Synthesis And Characterization Of Unsaturated Diacyl And Alkyl-Acyl Piperazine Derivatives, Sai̇t Sari, Seda Ünalan, Mehmet Yilmaz
Turkish Journal of Chemistry
The aim of this study is to obtain new unsaturated piperazine compounds by the reactions of piperazine (1a) and piperazine derivatives (1b-1d) with acylation reactive groups (a-2j). Methacryloyl piperazine (1b) was synthesized from the reaction of methacrylic anhydride with piperazine (1a). Acyl chlorides (2b-2d) were prepared from the reaction of thionyl chloride with carboxylic acids (3a-3c) obtained as a result of the reaction with malonic acid and suitable aldehyde (5-methylfuran-2-carbaldehyde for 3a, cinnamaldehyde for 3b, and thiophene-2-carbaldehyde for 3c), respectively, by literature methods. Acyl chlorides 2ed and 2f }were obtained from the reaction of commercially purchased carboxylic acids 3d and …
Aqueous Two-Phase Extraction Technique Based On Magnetic Ionic Liquid-Nonionic Surfactant For Phenolic Acids In Grape, Apple, Pear, And Banana, Taşkin Mumcu, Serap Seyhan Bozkurt
Aqueous Two-Phase Extraction Technique Based On Magnetic Ionic Liquid-Nonionic Surfactant For Phenolic Acids In Grape, Apple, Pear, And Banana, Taşkin Mumcu, Serap Seyhan Bozkurt
Turkish Journal of Chemistry
An aqueous two-phase extraction system was constituted using magnetic ionic liquid-nonionic surfactant for phenolic acids and the developed method was applied to apple, grape, pear, and banana samples. Ionic liquids based on imidazolium containing butyl, allyl, and benzyl groups were used for extraction. The parameters influencing the extraction efficiency such as volume of ionic liquids, type and amount of surfactant and salt, ultrasound extraction time, temperature, and sample pH were optimized. The extraction efficiencies of ionic liquids were compared for phenolic acids under optimized conditions. Limits of detection and limits of quantification were in the range of 1.34-1.56 μg L$^{-1\, …
An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk
An Ultrasensitive Electrochemical Immunosensor Platform Based On Disposable Ito Electrode Modified By 3-Cptms For Early Detection Of Parathyroid Hormone, İnci̇ Uludağ, Mustafa Kemal Sezgi̇ntürk
Turkish Journal of Chemistry
Parathyroid hormone (PTH) is a polypeptide containing 84 amino acids secreted by cells of the parathyroid glands. Imbalances of parathyroid levels cause medical problems such as osteoporosis, mental disorders, pancreatitis, kidney stones, cancer, and other symptoms. In this study, we aimed to design an ultrasensitive electrochemical immunosensor for PTH detection. Indium tin oxide (ITO) was used as an electrode for electrochemical impedance spectroscopy (EIS) measurements. ITO sheets were modified by using 3-cyanopropyltrimethoxysilane (3-CPTMS) self-assembled monolayers (SAMs) for immobilizing the anti-PTH antibody via covalent interactions. Cyclic voltammetry (CV) and EIS methods were applied to characterize immobilization steps. Therefore, 1% was selected …
The Role Of Diazacrown Ether In The Enhancement Of The Biological Activity Of Silver Nanoparticles, Sarvinaz Hajiyeva, Ulviyya Hasanova, Zarema Gakhramanova, Aygun Israyilova, Khudaverdi Ganbarov, Eldar Gasimov, Fuad Rzayev, Goncha Eyvazova, Alakbar Huseynzada, Gunel Aliyeva, Ilaha Hasanova, Abel Maharramov
The Role Of Diazacrown Ether In The Enhancement Of The Biological Activity Of Silver Nanoparticles, Sarvinaz Hajiyeva, Ulviyya Hasanova, Zarema Gakhramanova, Aygun Israyilova, Khudaverdi Ganbarov, Eldar Gasimov, Fuad Rzayev, Goncha Eyvazova, Alakbar Huseynzada, Gunel Aliyeva, Ilaha Hasanova, Abel Maharramov
Turkish Journal of Chemistry
The nanostructuring of hydroxyl-substituted diazacrown-ether (DC) by silver nanoparticles was obtained by green synthesis method in order to increase the antibacterial activity of silver nanoparticles. The synthesized DC, nanoparticles, and nanosupramolecular complex (Ag@DC) were studied by TEM, powder-XRD, and NMR, IR, and UV spectroscopy methods. The Ag@DC nanostructures were uniform and their sizes ranged from 8 to 18 nm. IR and UV spectra revealed the noncovalent formation of the nanosupramolecular complex. The antibacterial activities of the prepared active agents were investigated on gram-positive and gram-negative bacteria by twofold microdilution method. Ultrastructural study by TEM was performed on \textit{E. coli} BDU12 …
Determination Of Triacylglycerols And Fatty Acid Composition Of Chilopsis Linearis Seed Oil By Reverse-Phase High-Performance Liquid Chromatography, Anh Van Nguyen, Victor Ivanovic Deineka, Lyudmila Aleksandrovna Deineka, Anh Thi Ngoc Vu
Determination Of Triacylglycerols And Fatty Acid Composition Of Chilopsis Linearis Seed Oil By Reverse-Phase High-Performance Liquid Chromatography, Anh Van Nguyen, Victor Ivanovic Deineka, Lyudmila Aleksandrovna Deineka, Anh Thi Ngoc Vu
Turkish Journal of Chemistry
In the present work, the compositions of the 27 triacylglycerols (TAGs) as well as fatty acid composition of Chilopsis linearis seed oil were determined by reverse-phase high-performance liquid chromatography (RP-HPLC) with diode array and mass spectrometric detections. It was shown that the main conjugated acid in the seed oil is a catalpic acid, (9E,11E,13Z)-octadeca-9,11,13-trienoic acid, while two unusual fatty acids have the parameters satisfying the literature data for (10E,12E)-octadeca-10,12-dienoic and (9E,12E)-octadeca-9,12-dienoic acids. For the two conjugated acid substituents the isosbestic point (at 234 nm) was found and was used to calculate the ratios of TAGs with different chromophores in the …
Alpha-Pyrone Glycosides From Scutellaria Salviifolia Benth, Zeynep Doğan, Kan'ichiro Ishiuchi, Toshiaki Makino, İclal Saraçoğlu
Alpha-Pyrone Glycosides From Scutellaria Salviifolia Benth, Zeynep Doğan, Kan'ichiro Ishiuchi, Toshiaki Makino, İclal Saraçoğlu
Turkish Journal of Chemistry
Scutellaria salviifolia Benth. is an endemic species growing in Turkey that belongs to the family Lamiaceae. As a result of a phytochemical study on the aerial parts of S. salviifolia Benth., two new and 10 known compounds were isolated from the aqueous fraction of methanolic extract. The new compounds are methyl-$\alpha $-pyrone glucosides, 3,4-dihydroxy-6-methylpyran-2-one 3-$O$-$\beta $-glucopyranoside (=scusalvioside A, 1), and 3,4-dihydroxy-6-methylpyran-2-one 3-$O$-$\beta $-(6$'$-$O$-$E$-caffeoyl) glucopyranoside (=scusalvioside B, 2) with new skeletal structures. Along with them, 3 phloroglucinol glucosides [phlorin (3), tadehaginoside (4), and 6$^{\prime \prime} $-$O$-$Z$-$p$-coumaroyl phloroglucinol-1-$O$-$\beta $-glucopyranoside (5)], 6 flavonoids [apigenin (6), apigenin 5-$O$-$\beta $-glucopyranoside (7), isoschaftoside (8), luteolin 7-$O$-$\beta …
Comparative Study Of Solvent Extraction Of Molybdenum By Various Extractants, Abdoul Rachid Chaibou Yacouba, Salmana Laouali Ibrahim, Ibrahim Natatou
Comparative Study Of Solvent Extraction Of Molybdenum By Various Extractants, Abdoul Rachid Chaibou Yacouba, Salmana Laouali Ibrahim, Ibrahim Natatou
Turkish Journal of Chemistry
Solvent extraction of molybdenum from various acid media by Alamine 336, Aliquat 336, TOPO, and DEHPA in kerosene was studied. The extraction efficiency of molybdenum by diisobutyl ketone (DIBK), the effects of various parameters like diluents, mineral acids, extractant concentration, and applications of these extractants on molybdenum extraction contained in the uranium-bearing ore solutions were investigated. DIBK used as solvent can indeed extract the molybdenum without adding any extractants in the range of 20-50 mg/L. Molybdenum was extracted by Aliquat 336 in all mineral acids at more than 90%. On the basis of slope analysis, the compositions of the extracted …
Synthesis, Characterization, And Kinetic Studies Of Multifunctionalized Mesoporous Silica For Adsorption Of Zinc, Ali̇me Çitak
Synthesis, Characterization, And Kinetic Studies Of Multifunctionalized Mesoporous Silica For Adsorption Of Zinc, Ali̇me Çitak
Turkish Journal of Chemistry
The aim of this study is to evaluate the utilization of bifunctional mesoporous silica with a platinum and propylsulfonic acid group (Pt/SBA15-PrSO$_{3}$H) as an adsorbent for the removal of Zn(II) ions from aqueous solutions. The SBA15-functionalized organosulfonic acid material was synthesized with a one-step cocondensation synthesis route. The second step was Pt loading during reduction and deposition into the aqueous suspension of the bifunctional mesoporous silica synthesized by an aqueous solution of formaldehyde as the reducing agent. The propylsulfonic acid and platinum functionalized mesoporous silica were characterized by BET, thermogravimetric analysis, and X-ray diffraction methods. The adsorption properties and thermodynamic …
New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse
New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse
Turkish Journal of Chemistry
In the current study, four new phenolic oxime ligands (HL1ox-HL4ox) containing diazo groups (-N$=$N-) were synthesized and used for liquid-liquid extraction of heavy metal ions [Cu(II), Ni(II), and Zn(II)]. The new compounds were characterized by analytical and spectroscopic methods. Solid-state structures of HL1ox-HL3ox were determined by single-crystal X-ray diffraction studies. Hirshfeld surface analysis of the compounds was performed to determine the contribution of different intermolecular contacts to the stability of the structures. The HL1ox-HL4ox ligands showed higher extraction performance for Cu(II) ion than Ni(II) and Zn(II) ions. The effect of pH on extraction capacity was investigated and the oxime compounds …
Rapid And On-Site Electrochemical Detection Of Bisphenol A And Arsenic In Drinking Water Using A Novel Electrode Array, Yildiz Uludağ, Zehra Ölçer, Canan Doğan, Turghun Muhammad, Zeynep Altintaş
Rapid And On-Site Electrochemical Detection Of Bisphenol A And Arsenic In Drinking Water Using A Novel Electrode Array, Yildiz Uludağ, Zehra Ölçer, Canan Doğan, Turghun Muhammad, Zeynep Altintaş
Turkish Journal of Chemistry
The paper describes a novel dip-and-gauge hand-held sensor device for the rapid, cost-effective, and on-site detection of bisphenol A and arsenic in drinking water samples. Different working electrode diameters ranging from 1.5 mm to 4 mm were designed and fabricated to construct a new electrochemical biosensor. The sensor was employed for the chronoamperometric detection of bisphenol A and voltammetric determination of arsenic in drinking water samples. Bisphenol A measurements resulted in a detection limit of 10 ng mL$^{-1}$ with a linear range of 0-4000 ng mL$^{-1}$. Baby products and bottles have to be completely free of bisphenol and hence a …
Investigation Of The Structural And Physicochemical Requirements Of Quinoline-Arylamidine Hybrids For The Growth Inhibition Of K562 And Raji Leukemia Cells, Vesna Rastija, Marijana Jukic, Teuta Opacak-Bernardi, Luka Krstulovic, Ivana Stolic, Ljubica Glavac-Obrovac, Miroslav Bajic
Investigation Of The Structural And Physicochemical Requirements Of Quinoline-Arylamidine Hybrids For The Growth Inhibition Of K562 And Raji Leukemia Cells, Vesna Rastija, Marijana Jukic, Teuta Opacak-Bernardi, Luka Krstulovic, Ivana Stolic, Ljubica Glavac-Obrovac, Miroslav Bajic
Turkish Journal of Chemistry
Quantitative structure-activity relationship (QSAR) analysis of 28 quinoline-arylamidine (CQArA) hybrids against two leukemia cells, K562 and Raji, was performed. Multiple linear regression (MLR) models were obtained by genetic algorithm. The best models involved the following descriptors: radial distribution function (RDF) descriptors, GETAWAY (GEometry, Topology, and Atom-Weights AssemblY) descriptor, bond information content index, and dipole moment. The best MLR models for K562 and Raji cells demonstrated satisfactory stability in internal and external validation. Since the QSAR model for Raji cells has better predictive ability, two new highly potent CQArA analogues were proposed based on it. The QSAR models revealed important physicochemical …
An Efficient Protocol For The Synthesis Of Brominated Norbornene, Norbornadiene, And Benzonorbornadiene, Selçuk Eşsi̇z
An Efficient Protocol For The Synthesis Of Brominated Norbornene, Norbornadiene, And Benzonorbornadiene, Selçuk Eşsi̇z
Turkish Journal of Chemistry
An efficient protocol for the synthesis of 2-bromonorbornene, 2-bromonorbornadiene, 2-bromoben- zonorbornadiene, 2,3-dibromonorbornene, 2,3-dibromonorbornadiene, and 2,3-dibromobenzonorbornadiene in good yields has been developed. 1,2-Dibromotetrachloroethane is used as the brominating agent for these reactions. The results are discussed in comparison with alternative methods in the literature.
Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh
Anticorrosion Coating For Magnesium Alloys: Electrospun Superhydrophobic Polystyrene/Sio$_{2}$ Composite Fibers, Nesri̇n Horzum Polat, Özlem Kap, Ami̇r Farzaneh
Turkish Journal of Chemistry
Superhydrophobic nanocomposite coatings for magnesium surfaces with remarkable corrosion resistance were fabricated by electrospinning in the presence of fluorosilane-functionalized silica (SiO$_{2})$ nanoparticles. The effects of surface-modified silica (mod-SiO$_{2})$ nanoparticles on the superhydrophobicity and corrosion resistance of polystyrene (PS)/mod-SiO$_{2}$ fiber coatings were evaluated. The incorporation of the SiO$_{2}$ nanoparticles endows PS fibers with rough surfaces exhibiting a water contact angle (WCA) of 165$^{\circ}$. The surface wettability, corrosion resistance, and their relation to the inorganic content in the PS fibers and the contact angle of the composite coatings were explored. Analysis of the corrosion results confirmed that the PS/mod-SiO$_{2}$ coating protected the …
Solid-Phase Extraction Method For Preconcentration Of Cadmium And Lead In Environmental Samples Using Multiwalled Carbon Nanotubes, Ayman A. Gouda, Wael A. Zordok
Solid-Phase Extraction Method For Preconcentration Of Cadmium And Lead In Environmental Samples Using Multiwalled Carbon Nanotubes, Ayman A. Gouda, Wael A. Zordok
Turkish Journal of Chemistry
A new sensitive and accurate solid-phase extraction method for preconcentration of trace amounts of cadmium and lead in various environmental samples prior to flame atomic absorption spectrometry determination has been developed. The proposed method is based on the utilization of multiwalled carbon nanotubes in combination with 5-benzyl-4-[-chlororbenzylidene amine]-4H-1,2,4-triazole-3-thiol (BCBATT) as a solid-phase sorbent with the aid of ultrasonication. The effect of the preconcentration parameters was investigated. Good recoveries ranging from 95% to 102% with relative standard deviations of 3.2% and 2.8% for Cd$^{2+}$ and Pb$^{2+}$, respectively, were obtained, indicating high accuracy and precision. The limits of detection were 0.2 and …
Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng
Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng
Turkish Journal of Chemistry
Carbamates weaken the luminol-H$_{2}$O$_{2}$ chemiluminescence (CL) catalyzed by sodium copper chlorophyll (SCC). The capacity to inhibit the CL of three carbamates is in the order of carbaryl (CBL) \textgreater carbofuran (CBF) \textgreater metolcarb (MTC). Mechanisms of carbamates inhibiting SCC-luminol-H$_{2}$O$_{2}$ CL are investigated using fluorescence quenching and quantum chemistry simulations for the first time in this work. Carbamate-SCC interactions studied using fluorescence spectroscopy show that with the increasing concentration of the SCC, the fluorescence of carbamate is quenched regularly, and the quenching mechanism is a static quenching process. Binding constants ($K_{B})$ of the three carbamates with SCC are CBL (4.39 x …
Effect Of Ph And $\Beta$-Cyclodextrin On The Photophysical Properties Of Lamotrigine, Raed Ghanem, Fakhri Yousef, Omar Abu Awwad
Effect Of Ph And $\Beta$-Cyclodextrin On The Photophysical Properties Of Lamotrigine, Raed Ghanem, Fakhri Yousef, Omar Abu Awwad
Turkish Journal of Chemistry
Photophysical properties of lamotrigine (LMT) were investigated at different pH values. Lamotrigine exhibited a broad absorption band at 308 nm that was shifted to 268 nm at pH 2.0 due to protonation (HLMT$+)$. Emission spectra of LMT at different pH values showed a single band at 483 nm except for at pH 2.0, where a second band at 502 nm was observed due to the deprotonation from the singlet excited state. LMT pH profile was used to calculate p$K$a of LMT in excited and ground states (p$K$a* $=$ 4.50 and p$K$a $=$ 5.90). Absorption spectra of LMT at different pH …
Synthesis And Some Optical Results Of Long Chain Substituted Phthalocyanines, İbrahi̇m Özçeşmeci̇, İdri̇s Sorar
Synthesis And Some Optical Results Of Long Chain Substituted Phthalocyanines, İbrahi̇m Özçeşmeci̇, İdri̇s Sorar
Turkish Journal of Chemistry
Four metallo (zinc, copper, vanadyl, and indium) phthalocyanine derivatives bearing four aliphatic (hexylthio) groups were prepared from corresponding phthalonitrile compounds. The metallophthalocyanines were characterized with ultraviolet–visible spectroscopy (UV-Vis), proton nuclear magnetic resonance (1H NMR), Fourier transform-infrared spectroscopy (FT-IR), and mass and elemental analyses techniques. Aggregation properties of metallophthalocyanines in solution were studied in varied concentration ranges. Thin films of metallophthalocyanines were obtained by spin coating technique. Optical measurements showed that transmittance values of metallophthalocyanine thin films obviously changed with respect to the metal ion in the phthalocyanines. Transmittance spectra of the phthalocyanines synthesized using different metal ions showed a variation …
Facile Synthesis Of Heteroaryl Substituted -Lactams From Nitrovinyl Arenes, Seda Çinar, Canan Ünaleroğlu
Facile Synthesis Of Heteroaryl Substituted -Lactams From Nitrovinyl Arenes, Seda Çinar, Canan Ünaleroğlu
Turkish Journal of Chemistry
Aliphatic nitroalkanes with different functional groups were synthesized from the Michael addition reactions of active methylene compounds 2 and nitrovinyl arenes 1 in high yields. The synthesized Michael adducts were subjected to intramolecular cyclization to give heteroaryl substituted γ-lactams in good to high yields under mild reaction conditions.
Sodium Borohydride For The Near-Future Energy: A ''Rough Diamond'' For Turkey, Ümi̇t Bi̇lge Demi̇rci̇
Sodium Borohydride For The Near-Future Energy: A ''Rough Diamond'' For Turkey, Ümi̇t Bi̇lge Demi̇rci̇
Turkish Journal of Chemistry
Boron-based materials are potential solutions in the field of energy. They have been regarded as hydrogen storage materials, liquid fuels of direct liquid-fed fuel cells (DLFCs), electrolytes of battery, and/or energetic substances. A typical example is sodium borohydride (NaBH$_{4}$. In sodium hydroxide-stabilized aqueous solutions, it is seen as an efficient H$_{2}$ generator or a performing fuel of DLFCs. Actually, it plays a wider role; it is also the precursor of several boron-based materials of interest in the field of energy. In other words, it is indirectly considered for other energy applications, i.e. solid electrolytes of all solid-state batteries and hypergolic …