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Full-Text Articles in Physical Sciences and Mathematics

Spectroscopic And Thermodynamic Approach To The Interaction Of Nonperipherally Substituted Cationic Phthalocyanines With Calf Thymus (Ct)-Dna, Sevgi̇can Tuncer, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Ayfer Kalkan Burat Jan 2018

Spectroscopic And Thermodynamic Approach To The Interaction Of Nonperipherally Substituted Cationic Phthalocyanines With Calf Thymus (Ct)-Dna, Sevgi̇can Tuncer, İbrahi̇m Özçeşmeci̇, Behi̇ce Şebnem Sesalan, Ayfer Kalkan Burat

Turkish Journal of Chemistry

Novel, nonperipherally tetrasubstituted cationic metal-free and metallophthalocyanines (Zn, In) were synthesized in the present study. The binding constants, the disappearance of quenching effect of all cationic phthalocyanines on the fluorescence intensity of SYBR Green--disodium salt of deoxyribonucleic acid (DNA) from calf thymus complex, and the changes in T$_{m}$ of double helix DNA with thermal denaturation profile were investigated by UV-Vis and fluorescence spectrophotometric methods. To investigate the spontaneity of the reactions between DNA and novel quaternized phthalocyanines in buffer, thermodynamic parameters were employed.


Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik Jan 2018

Transfer Of The Protonable Surfactant Dipalmitoyl-Phosphatidylcholine Across A Large Liquid/Liquid Interface: A Voltammetric Study, İbrahi̇m Uyanik

Turkish Journal of Chemistry

Adsorption behavior of the zwitterionic phospholipid dipalmitoyl-phosphatidylcholine (DPPC) at the polarizable liquid/liquid interface formed between water and 1,2-dichloroethane electrolyte solutions is studied taking into account both the pH of the aqueous phase and the concentration of the phospholipid in the organic phase by cyclic voltammetry. Experimental results showed that the adsorption of the phospholipid strongly depends on the pH of the aqueous phase, which determines the surface ionization of the polar head of the phospholipid molecule and hence the stability of the adsorbed layer of phospholipids.


Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül Jan 2018

Experimental And Theoretical Studies Of Carbazole-Based Schiff Base As A Fluorescent Fe$^{3+}$ Probe, Hakan Kandemi̇r, Abdulkadi̇r Koçak, Süreyya Oğuz Tümay, Bünyemi̇n Çoşut, Yunus Zorlu, İbrahi̇m Fazil Şengül

Turkish Journal of Chemistry

Synthesis of a new (E)-N1-((9-ethyl-9H-carbazol-3-yl)methylene)-5-nitrobenzene-1,2-diamine as a fluorescent chemosensor for selective detection of Fe$^{3+}$ ion over a number of other metal ions is described. The method for the synthesis of the carbazole Schiff base was based on the condensation of carbazole-3-carbaldehyde with 4-nitro-o-phenyldiamine in dimethylformamide in a moderate yield. The structure of the final compound was characterized by $^{1}$H NMR, $^{13}$C NMR, IR, mass spectrometry, and single crystal X-ray diffraction. The final compound exhibited exceptional selective and sensitive turn-on fluorescence response to the Fe$^{3+}$ cation. The fluorescent intensity of the final compound was increased 20-fold and the stoichiometry ratio of …


Tetrahydronaphthalene As A Precursor Of New Series Of Chalcones, Flavanones, And Flavones, Ahmed Meddeb, Ghalia Bouhalleb, Julien Legros, Farhat Rezgui Jan 2018

Tetrahydronaphthalene As A Precursor Of New Series Of Chalcones, Flavanones, And Flavones, Ahmed Meddeb, Ghalia Bouhalleb, Julien Legros, Farhat Rezgui

Turkish Journal of Chemistry

An efficient synthetic route for a novel series of chalcones 2a-2d as well as for the corresponding flavanones 3a-3d and flavones 4a-4d, using functionalized tetrahydronaphthalene (THN), is described herein. The Claisen-Schmidt condensation of such THN and aromatic aldehydes, in the presence of an aqueous solution of KOH (40%), selectively gives the expected chalcones 2a-2d, which may further undergo an intramolecular oxa-Michael addition using piperidine, affording the corresponding flavanones 3a-3d in high yields. Alternatively, treatment of such chalcones 2a-2d with I$_{2}$/DMSO provides rapidly, in a one-pot oxidative cyclization, a series of flavones 4a-4d in excellent yields ranging from 85% to 90%.


Simultaneous Determination Of Copper(Ii) And Zinc(Ii) Via Simple Acid-Base Titrimetry Using Glass Ph Electrode, Emi̇ne Gül Cansu Ergün, Adnan Kenar Jan 2018

Simultaneous Determination Of Copper(Ii) And Zinc(Ii) Via Simple Acid-Base Titrimetry Using Glass Ph Electrode, Emi̇ne Gül Cansu Ergün, Adnan Kenar

Turkish Journal of Chemistry

The combination of potentiometric methods with multivariate calibration techniques allows complex mixtures to be analyzed. In this study, a new method was developed and reported for simultaneous determination of copper(II) and zinc(II) cations in a mixture by titrimetric methods. The developed method permits simultaneous cation analysis with low detection limits, just by using a pH electrode. This work has achieved the challenging goal of developing a cost-effective and applicable method that can be applied in most laboratories due to independence of any chemical instruments. Partial least squares 1, one of the multivariate calibration techniques, was used in the analysis of …


Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz Jan 2018

Synthesis And Biological Properties Of Novel1-Methyl-2-(2-(Prop-2-Yn-1-Yloxy)Benzylidene) Hydrazine Analogues, Ari̇f Kivrak, Can Yilmaz, Meti̇n Konuş, Hali̇l Koca, Selahatti̇n Aydemi̇r, Jeger Ali Oagaz

Turkish Journal of Chemistry

1-Methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazine analogues were readily prepared in good yields by the reaction of 2-(prop-2-yn-1-yloxy)benzaldehydes and methyl hydrazine. The reaction tolerates a variety of substituents on the 2-hydroxybenzaldehyde to form nitro-, halo-, methoxy-, and naphthyl-substituted 1-methyl-2-(2-(prop-2-yn-1-yloxy)benzylidene)hydrazines. The in vitro antioxidant capacity measurements revealed that among all the analyzed hydrazine analogues that surpassed the Trolox standard, 1-(2-(but-3-ynyl)-5-nitrobenzylidene)-2-methylhydrazine had the maximum value, which was approximately 1.7 times that of Trolox.


The Synthesis Of New Oxindoles As Analogs Of Natural Product 3,3$^\Prime $-Bis(Indolyl)Oxindole And In Vitro Evaluation Of The Enzyme Activity Of G6pd And 6pgd, Si̇nan Bayindir, Adnan Ayna, Yusuf Temel, Mehmet Çi̇ftci̇ Jan 2018

The Synthesis Of New Oxindoles As Analogs Of Natural Product 3,3$^\Prime $-Bis(Indolyl)Oxindole And In Vitro Evaluation Of The Enzyme Activity Of G6pd And 6pgd, Si̇nan Bayindir, Adnan Ayna, Yusuf Temel, Mehmet Çi̇ftci̇

Turkish Journal of Chemistry

Natural and synthetic derivatives that contain an indole core are being used in medical treatments and technological processes. Therefore, the development of new synthetic methods for the synthesis of indole derivatives is very popular. In this study, new oxindoles with reaction of 4,7-dihydro-1$H$-indole (2) and isatin (4) were synthesized as analogs of natural product 3,3$^\prime $-bis(indolyl)oxindole. The biological properties of the compounds obtained during this study were also studied, showing that compounds 5, 7, and 12 inhibited the activity of G6PD with an IC$_{50}$ of 99 $\mu $M, 231 $\mu $M, and 304 $\mu $M respectively. The activity of rat …


Protein Ion-Exchange Chromatography On A Biomacromolecule-Immobilized Monolithic Cryogel, Ahmet Eren Özkan, Idris Guven, Orhan Gezici Jan 2018

Protein Ion-Exchange Chromatography On A Biomacromolecule-Immobilized Monolithic Cryogel, Ahmet Eren Özkan, Idris Guven, Orhan Gezici

Turkish Journal of Chemistry

An efficient and inexpensive monolithic stationary phase (PHEMA-HA) has been prepared through an easy process comprising addition of humic acid (HA) to a mixture of 2-hydroxyethyl methacrylate (HEMA) and N,N'-methylenebisacrylamide (MBAAm) and subsequent radical-polymerization at -20 $^{\circ}$C. The prepared monolithic material was characterized in terms of various techniques and methods such as elemental analysis, FTIR spectroscopy, scanning electron microscopy, mercury porosimetry, hydrolytic stability tests, pH$_{pzc}$ measurements, water-holding capacity, and water permeability. The amount of HA incorporated into the structure was calculated as 45 mg/g from the elemental analysis results. The study was conceptualized on the basis of protein ion-exchange chromatography, …


Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven Jan 2018

Nickel(Ii)-Pph$_{3}$ Complexes With Ons And Onn Chelating Thiosemicarbazones: Synthesis And Inhibition Potential On Influenza A Viruses, Şükri̇ye Güveli̇, Kadi̇r Turan, Bahri̇ Ülküseven

Turkish Journal of Chemistry

Tetra-coordinated nickel(II) complexes of two ONS (1, \2) and seven ONN (3a-3g) chelating 2-hydroxy-3-methoxy-benzaldehyde thiosemicarbazones were synthesized. The dibasic ligands and complexes bearing PPh$_{3}$ as a coligand were characterized by means of analytical and spectroscopic data. Cytotoxic activities of the ligands and nickel(II) complexes were determined using the MTT assay in vitro against MDCK cells, and then all the compounds were tested on influenza virus replication by plaque assays. The compounds showed GI$_{50}$ values varying from concentrations of 15.9 up to 161.8 $\mu$ g/mL for MDCK cells. The plaque assays indicated that one ONS (1) and two ONN (3c and …


Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top Jan 2018

Peg-Peptide Conjugate Containing Cathepsin B Degradation Unit As A Doxorubicin Carrier System, Nesli̇gül Şentürk, Ayben Top

Turkish Journal of Chemistry

A drug delivery system (DDS) containing a cathepsin B degradable sequence and pH-responsive histidines was prepared by methoxypolyethylene glycol and peptide conjugation. Doxorubicin was attached to the carrier system using amide linkage to give the final form of the DDS, denoted as mPEG-AT3-DOX. mPEG-AT3-DOX exhibited a bimodal size distribution at about 15 and 30 nm independent of pH, whereas the size of the control DDS containing no peptide sequence, mPEG-DOX, was measured as $\sim$ 15-20 nm. At the end of 72 h, % doxorubicin release from both of the DDSs was observed to be below 8.5 $\pm$ 3% in the …


Synthesis, Biological Evaluation, And In Silico Study Of Some Unique Multifunctional 1,2,4-Triazole Acetamides, Almas Sattar, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Hira Khalid, Muhammad Arif Lodhi, Farman Ali Khan Jan 2018

Synthesis, Biological Evaluation, And In Silico Study Of Some Unique Multifunctional 1,2,4-Triazole Acetamides, Almas Sattar, Aziz Ur Rehman, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Hira Khalid, Muhammad Arif Lodhi, Farman Ali Khan

Turkish Journal of Chemistry

The imperative demand for antibacterial agents and enzyme inhibitors prompted us to synthesize some new compounds, 6a-6k, bearing multifunctional moieties. The target acetamides were derived from 4-phenyl-5-(1-tosylpiperidin-4-yl)-4$H$-1,2,4-triazole-3-thiol (3). The structural analysis was carried out using modern spectroscopic techniques including IR, NMR, and EIMS spectral analysis. The antibacterial activity was screened against five bacterial strains including three gram-negative and two gram-positive ones. Enzyme inhibition was carried out against lipoxygenase enzyme and results were supported by in silico study. The synthesized compounds were proved to be potent antibacterial agents and enzyme inhibitors.


Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov Jan 2018

Oxime-Containing Acetylcholinesterase Reactivators And Their Complexes With Pd(Ii) And Pt(Ii) Ions: Recent Developments, Ivayla Pantcheva, Ahmed Nedzhib, Liudmil Antonov

Turkish Journal of Chemistry

The ability of oxime-containing acetylcholinesterase reactivators BT-07 (K005), BT-08 (K033), BT-07-4M (K074), and obidoxime (H$_{2}$LX$_{2}$, X = Cl$^{-}$, Br$^{-})$ to bind palladium(II) or platinum(II) cations was evaluated in aqueous solutions (pH 7.4) at metal-to-ligand molar ratio varying from 1:10 to 10:1. Spectral changes were monitored within a week after mixing the reagents in the range from 220 nm to 500 nm. Results showed that depending on chemical structure and reaction time, oximes form two complex species of composition, [MHL]$^{3+}$ or [M$_{2}$L]$^{4+}$ (M = Pd(II), Pt(II)). It was also found that complexation of platinum(II) ions proceeds slower as compared to palladium(II). …


A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak Jan 2018

A Novel Hypobromous Acid Scavenging Activity Assay Using $P$-Cresol As A Spectrofluorometric Probe, Burcu Bekdeşer, Gülüzar Zeytünlü, Mustafa Özyürek, Mustafa Reşat Apak

Turkish Journal of Chemistry

In this study, a novel spectrofluorometric assay based on $p$-cresol (4-methyl phenol) probe is developed for the measurement of HOBr scavenging activity. It is the first study involving the use of a $p$-cresol probe for the determination of the HOBr scavenging activity of biothiols. While the $p$-cresol probe ($\lambda_{ex}$ = 260 nm, $\lambda_{em}$ = 305 nm) has fluorescence characteristics, its brominated derivatives emerging at the end of the oxidation reaction with HOBr do not show fluorescence. The initial fluorescence intensity of the $p$-cresol probe is decreased in the presence of the brominating agent, HOBr, and this decrease is lower in …


Electrochemical Polymerization Of A New Alkoxy-Bridged Dithieno (3,2-B:2',3'-D) Pyrrole Derivative, Ari̇f Kivrak, Hüseyi̇n Beki̇r Yildiz, Selahatti̇n Gökyer, Buket Çarbaş Jan 2018

Electrochemical Polymerization Of A New Alkoxy-Bridged Dithieno (3,2-B:2',3'-D) Pyrrole Derivative, Ari̇f Kivrak, Hüseyi̇n Beki̇r Yildiz, Selahatti̇n Gökyer, Buket Çarbaş

Turkish Journal of Chemistry

A novel alkoxy-bridged dithieno (3, 2-B:2',3'-D) pyrrole (DTP) derivative was synthesized and its corresponding polymer poly(1,2-bis(2-(4H-dithieno[3,2-b:2',3'-d]pyrrol-4-yl)ethoxy)ethane) (P(DTP-alkoxy-DTP)) was successfully obtained electrochemically. The effects of alkoxy bridge in the structure on the electrochemical and spectroelectrochemical properties of the polymer were also investigated in detail. The results showed that the polymer film exhibits multielectrochromic behavior and a low band gap of 1.82 eV.


Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal Jan 2018

Application Of A Pencil Graphite Electrode For Voltammetric Simultaneous Determination Of Ascorbic Acid, Norepinephrine, And Uric Acid In Real Samples, Abdulkadi̇r Levent, Günay Önal

Turkish Journal of Chemistry

A pencil graphite electrode (PGE) was used for the simultaneous detection of ascorbic acid (AA), norepinephrine (NE), and uric acid (UA) by differential pulse voltammetry and cyclic voltammetry. The anodic peaks of AA, NE, and UA in their mixture can be well separated in 0.1 M Britton--Robinson buffer solution at pH 4.0. The effects of various experimental parameters such as pH, scan rate, and voltammetric parameters on the voltammetric response of these compounds were investigated. Under optimum conditions, linear calibration graphs were obtained from the AA, NE, and UA concentration ranges, which were 100-800 nM, 20-170 nM, and 40-175 nM, …


Application Of The Taguchi Approach To Optimize Zno Synthesis Via Hydrothermally Assisted Sol-Gel Method, Zahra Khaghanpour, Sanaz Naghibi Jan 2018

Application Of The Taguchi Approach To Optimize Zno Synthesis Via Hydrothermally Assisted Sol-Gel Method, Zahra Khaghanpour, Sanaz Naghibi

Turkish Journal of Chemistry

ZnO powder was synthesized via a hydrothermally assisted sol-gel method. Synthesis variables including Zn-precursor type, pH value, time, and temperature of hydrothermal treatment were analyzed using the Taguchi approach. The experimental procedures were defined based on the L9 array for four variables in three levels. The influences of those variables on the response parameters, i.e. crystallite size, crystallinity, band gap energy ($E_{g})$, and degradation constants ($k)$, were evaluated. XRD results and $E_{g}$ values showed that ZnO wurtzite appeared to be the only crystalline phase in the samples. Taguchi analysis predicted that the optimized conditions to achieve the highest photoactivity are …


Influence Of Manganese Content On The Supercapacitive Performance Of Pbo$_{2}$-Mno$_{2}$ Electrodes, Yingwu Yao, Mengyao Li, Xinghua Zhang, Zunming Lu, Feng Wei Jan 2018

Influence Of Manganese Content On The Supercapacitive Performance Of Pbo$_{2}$-Mno$_{2}$ Electrodes, Yingwu Yao, Mengyao Li, Xinghua Zhang, Zunming Lu, Feng Wei

Turkish Journal of Chemistry

PbO$_{2}$-MnO$_{2}$ electrodes were prepared by electrochemical codeposition methods. The electrodes were characterized by scanning electron microscope, X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The content of manganese in the electrodes increased with the increase in manganese ion concentration in the solution, which can reach 48.4%. The codeposition of manganese decreased the grain sizes and formed the porous structure. Cyclic voltammetry and galvanostatic charge-discharge measurements were used to evaluate the influence of manganese content in the electrodes on the specific capacitive performance of PbO$_{2}$-MnO$_{2}$ electrodes. The specific capacitance of PbO$_{2}$-MnO$_{2}$ (48.4%) electrodes could reach 374.5 F g$^{-1}$. The …


Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇ Jan 2018

Removal Of Five Cationic Dyes Using A Resin Coated With Nickel/Nickel Boride Nanoparticles, Merve Çinar, Yasemi̇n İşlek Coşkun, Tüli̇n Deni̇z Çi̇ftçi̇

Turkish Journal of Chemistry

Resins coated with nickel/nickel boride nanoparticles were used to remove brilliant green, methyl violet, methylene blue, phenosafranine, and brilliant cresyl blue from water. The effects of pH, adsorbent dose, contact time, and initial dye concentration on the adsorption efficiencies were investigated. The point of zero charge for the adsorbent was pH 9.5. Isotherm studies were conducted using Langmuir, Freundlich, and Dubinin--Radushkevich models, and thermodynamic studies were also performed. Adsorption of the five dyes was found to obey the Langmuir isotherm model and was endothermic. The maximum adsorption capacities calculated from the Langmuir isotherm were 66.7, 88.5, 144.9, 56.2, and 147.1 …


Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi Jan 2018

Multiwall Carbon Nanotube Paste Electrode As A Sensor For Sensitive Determination Of Deferasirox In The Presence Of Uric Acid: Application For The Analysis Of Pharmaceutical And Biological Samples, Golnaz Parvizi Fard, Reza Emamali Sabzi

Turkish Journal of Chemistry

In this work, the electrochemical oxidation of deferasirox at a multiwall carbon nanotube paste electrode (MWCNTPE) was described. The electrochemical behavior of deferasirox was studied using cyclic voltammetry and chronoamperometry techniques and parameters such as charge transfer coefficient ($\alpha )$, the number of electrons involved in the rate-determining step ($n_{a})$, and diffusion coefficient ($D)$ were calculated. The capability of the electrode for the determination of deferasirox at low concentrations was investigated using the differential pulse voltammetry technique. It was found that the calibration graph of deferasirox was linear in the concentration range of 0.16-16.5 $\mu $M and its detection limit …


Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün Jan 2018

Synthesis And Characterization Of New Thiophene--Benzimidazole-Based Electrochromes, Emi̇ne Gül Cansu Ergün

Turkish Journal of Chemistry

In the present study, two new donor--acceptor--donor-type molecules were synthesized and the electro-optical properties of the resulting monomers and their corresponding polymers were investigated. Thiophene was selected as the donor unit and cycloheptyl- and cyclooctyl- substituted benzimidazoles were used as the acceptor units. The synthesized monomers and their electrochemically obtained polymers were characterized using cyclic voltammetry and UV-Vis spectrometry. The optical band gap values of the polymers were 1.62 eV and the polymer films changed color to gray upon oxidation, while they were brick red in their neutral states. Moreover, changing the ring size on the acceptor group from seven …


Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro Jan 2018

Adsorptive Properties Of Mesoporous Silica Modified With Lewis Base Molecule And Its Application In The Preconcentration Of Cu(Ii), Co(Ii), And Cd(Ii) From Aqueous Media, Janaíne Do Rócio Ivassechen, Alexandre De Oliveira Jorgetto, Marcos Henrique Pereira Wondracek, Adrielli Cristina Peres Da Silva, Luiz Fabrício Zara, Valber De Albuquerque Pedrosa, Bruno Prior Rocha, Margarida Juri Saeki, Gustavo Rocha Castro

Turkish Journal of Chemistry

Cocondensation and postfunctionalization methods were employed to synthesize a mesoporous silica with large surface area (795.1 $\pm $ 1.1 m$^{2}$ g$^{-1})$ modified with 4-amino-5-hydrazino-1,2,4-triazole-3-thiol, which was successfully applied to adsorb and preconcentrate Cu(II), Co(II), and Cd(II) from aqueous media. Infrared spectroscopy of the adsorbent material demonstrated N-H stretching bonds related to primary amines existing in the ligand molecule, elemental analysis revealed the presence of 0.132 mmol g$^{-1}$ of nitrogen, scanning electron microscopy indicated globularly shaped particles with average size of 10 $\mu $m, and the point of zero charge was found to be 7.2. Kinetic data were applied to the …


Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz Jan 2018

Ligand Binding Constants Of The Cucurbit[7]Uril Predicted With Molecular Docking: A Theoretical Study, Balázs Roósz, Tamás Körtvélyesi, Béla Viskolcz

Turkish Journal of Chemistry

A binding stability order predicting, molecular docking based fast technique was developed for host--guest complexes. Molecular descriptors were applied to ligand molecules to make the binding energy based docking scoring functions more efficient and reach the $\pm $0.50 log K unit theoretical precision for predictions. The goal of this work was to model complexes of cucurbit[7]uril (CB7) as a host molecule with different local anesthetics and choline and phosphonium choline molecules. The guest molecules were docked into the cavity of CB7. The binding free energy maps were correlated by Contact, Grid-Based, Hawkins GB/SA, and AMBER docking scores obtained from UCSF …


Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek Jan 2018

Recent Advances In Organ-On-A-Chip Technologies And Future Challenges: A Review, Hüseyi̇n Avci, Fatma Doğan Güzel, Sali̇m Erol, Ali̇ Akpek

Turkish Journal of Chemistry

The significant development in the construction of microscale cell culture platforms and the interest in bioanalytical analysis have recently resulted in the emergence of a new concept of `organ-on-a-chip' systems. Organ-on-a-chip is a new three-dimensional (3D) in vitro microfabricated unit that contains a multichannel microfluidic cell culture. Even if many informative and useful data are obtained from animal models and in vitro assays, they are still limited for extrapolation to human systems during drug design and development. Only about 1 out of 10,000 compounds is processed in clinical trials for final approval. As being the first example of its kind, …


Enhanced Electrocatalytic Activity Of Copper Phthalocyanine/Multiwalled Carbon Nanotube Composite Electrode Via Pt Nanoparticle Modification For Oxygen Reduction, Çağri Ceylan Koçak, Zekerya Dursun Jan 2018

Enhanced Electrocatalytic Activity Of Copper Phthalocyanine/Multiwalled Carbon Nanotube Composite Electrode Via Pt Nanoparticle Modification For Oxygen Reduction, Çağri Ceylan Koçak, Zekerya Dursun

Turkish Journal of Chemistry

Enhanced electrocatalytic reduction of oxygen is achieved using Pt nanoparticle-modified copper phthalocya- nine-multiwalled carbon nanotube (PtNPs/CuPc-CNT) composite film on a glassy carbon electrode (PtNPs/CuPc-CNT/GCE). The PtNPs/CuPc-CNT/GCE surface is characterized by scanning electron microscopy, transmission electron microscopy, electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The electrocatalytic activity of composite electrodes in the oxygen reduction reaction is investigated by cyclic voltammetry and rotating-disk electrode measurements. PtNPs/CuPc-CNT/GCE show higher catalytic activity than CNT/GCE, CuPc/GCE, and CuPc-CNT/GCE in oxygen reduction with four electron transfers.


Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir Jan 2018

Schiff Base Of Isoniazid And Ketoprofen: Synthesis, X-Ray Crystallographic, Spectroscopic, Antioxidant, And Computational Studies, Naima Rehman, Muhammad Khalid, Moazzam Hussain Bhatti, Uzma Yunus, Ataualpa Albert Carmo Braga, Faiz Ahmed, Syed Muddassir Ali Mashhadi, Muhammad Nawaz Tahir

Turkish Journal of Chemistry

Ketoprofen and isoniazid together are a potential combination of a nonsteroidal antiinflammatory drug and an antitubercular medicine to treat tuberculosis and associated symptoms like fever and fatigue. The Schiff base of isoniazid with ketoprofen is synthesized in this research. Infrared spectroscopy (IR) and X-ray diffraction (XRD) analysis of the crystal packing proved the formation of the Schiff base and the existence of N-H$\cdot \cdot \cdot $O hydrogen bonds between the hydrogen-bonded dimer of the Schiff base. The complete geometrical optimization of the monomer and hydrogen-bonded dimer of the Schiff base is performed utilizing M06-2X/6-31G(d,p) level theory and compared with the …


$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan Jan 2018

$S$-Substituted Derivatives Of 1,2,4-Triazol-3-Thiol As New Drug Candidates For Type Ii Diabetes, Aziz Ur Rehman, Khadija Nafeesa, Muhammad Athar Abbasi, Sabahat Zahra Saddiqui, Shahid Rasool, Syed Adnan Ali Shah, Muhammad Ashraf, Muhammad Arif Lodhi, Farman Ali Khan, Bakht Jahan

Turkish Journal of Chemistry

The therapeutic applications of 1,2,4-triazoles motivated us to synthesize some new derivatives. Two series of $S$-substituted derivatives (8a-8j, 12a-12i) of 5-$\{$1-[(4-chlorophenyl)sulfonyl]-3-piperidinyl$\}$-4-phenyl-4$H$-1,2,4-triazol-3-thiol (6) have been synthesized and evaluated for their biological potential. Using 4-chlorobenzene sulfonyl chloride (1) and ethyl piperidine-3-carboxylate (2), ethyl 1-[(4-chlorophenyl)sulfonyl]piperidine-3-carboxylate (3) was synthesized and converted into 3,4,5-trisubstituted 1,2,4-triazole (6) through formation of the corresponding carbohydrazide (4) and hydrazinecarbothioamide (5). Compound 6 was transformed into 8a-8j by alkyl halides (7a-7j) and into 12a-12i by $N$-aralkyl/aryl-2-bromoacetamides (11a-11i) in an aprotic solvent. The electrophiles, 11a-11i, were synthesized by gearing up $N$-substituted aralkyl/aryl amines (10a-10i) with 2-bromoacetyl bromide (9) under dynamic pH …


Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng Jan 2018

Photocatalytic Degradation Of The Herbicide Quinclorac In Water Using Mn (Iii) Salen And Solar Light, Yisi Yang, Yan Zhang, Qingru Zeng

Turkish Journal of Chemistry

Quinclorac (QNC) is a widely used herbicide and is persistent in surface and ground waters. Its residuals and converted products are hazardous to aquatic animals, vegetation, and microbes, and it is therefore important to degrade QNC using an efficient and environmental friendly technology. In this study, the photocatalytical degradation of QNC using [(R,R)-(N,N$'$-bis(3,5,3$'$,5$'$-tetra-tert-butylsalicylidene)-1,2-cyclohexanediaminato] manganese(III) acetate (Mn (III) salen) and H$_{2}$O$_{2}$ was performed under natural sunlight irradiation and a 91% degradation rate was achieved in neutral pure water in 240 min. The identified degradation products confirmed that the cleavage of QNC molecules was the main process involved in the hydroxylation, along …


Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m Jan 2018

Synthesis And Characterization Of Novel Unsymmetrical Phthalocyanine/Tio$_{2}$ Composites And Their Evaluation As Photocatalysts For Degradation Of 4-Chlorophenol Under Visible Light, Yunus Alp Sütcüler, Görkem Gezek, Yaghub Mahmi̇ani̇, Altuğ Mert Sevi̇m

Turkish Journal of Chemistry

We prepared novel unsymmetrical A$_{3}$B-type zinc and cobalt phthalocyanines bearing monocarboxylic acid groups on peripheral positions using statistical condensation method, especially designed to anchor on the TiO$_{2}$ semiconductor surface. The novel complexes were anchored on TiO$_{2}$ semiconductor to prepare effective dye sensitized photoactive composites as heterogeneous catalysts. The results indicated that modified TiO$_{2}$ nanocrystals possessed only the anatase phase and MPc-TiO$_{2}$ photocatalysts with loading amount of dye ca. 8.27 $\mu $mol/g TiO$_{2}$ exhibit strong visible light absorption. Photocatalytic degradation of 4-chlorophenol (4-CP) under illumination with visible light ($\lambda >$ 400 nm) was tested with the composites prepared. The degradation profile …


One-Pot Synthesis Of Substituted 4$H$-Chromenes By Nickel Ferrite Nanoparticles As An Efficient And Magnetically Reusable Catalyst, Hamideh Ahankar, Ali Ramazani, Katararzyna Slepokura, Tadeusz Lis, Sang Woo Joo Jan 2018

One-Pot Synthesis Of Substituted 4$H$-Chromenes By Nickel Ferrite Nanoparticles As An Efficient And Magnetically Reusable Catalyst, Hamideh Ahankar, Ali Ramazani, Katararzyna Slepokura, Tadeusz Lis, Sang Woo Joo

Turkish Journal of Chemistry

Nickel ferrite magnetic nanoparticles (NiFe$_{2}$O$_{4}$ MNPs) were prepared via the autocombustion assisted sol-gel method. The efficient catalyst was investigated by FT-IR, XRD, ICP, SEM, and TEM techniques. A one-pot, three-component reaction is reported for the synthesis of substituted 4$H$-chromenes in the presence of NiFe$_{2}$O$_{4}$ MNPs as a reusable catalyst in a green solvent at 40 $^{\circ}$C under clean, efficient, and mild conditions. Furthermore, selected products were characterized by FT-IR, $^{1}$H NMR, and $^{13}$C NMR. The single-crystal X-ray analysis of product 4u was also conclusively confirmed. Easy workup procedure, high purity of products via simple recrystallization, and environmentally benign conditions are …


Environmental Impact Assessment Of Natural Radioactivity And Heavy Metals In Drinking Water Around Akkuyu Nuclear Power Plant In Mersin Province, Gürsel Karahan, Hali̇m Taşkin, Nesli̇ Bi̇ngöldağ, Eni̇s Kapdan, Yusuf Zi̇ya Yilmaz Jan 2018

Environmental Impact Assessment Of Natural Radioactivity And Heavy Metals In Drinking Water Around Akkuyu Nuclear Power Plant In Mersin Province, Gürsel Karahan, Hali̇m Taşkin, Nesli̇ Bi̇ngöldağ, Eni̇s Kapdan, Yusuf Zi̇ya Yilmaz

Turkish Journal of Chemistry

The aim of this study was to determine natural radioactive and heavy element concentrations in Mersin drinking water samples before the commissioning of the Akkuyu nuclear power plant and to collect data for possible environmental contaminations in the future. Drinking water samples were taken from the provincial center, districts, and populated villages. The annual effective dose of natural radionuclides and cancer risks were calculated for each person living in the city. Hazard index and cancer risk were calculated, which were caused by heavy elements. Mean gross alpha and beta radioactivity concentrations in drinking water were 0.059 Bq/L and 0.120 Bq/L, …