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Articles 65161 - 65190 of 294391

Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli Jan 2022

Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli

Turkish Journal of Chemistry

In this study, 7 new isoxazole compounds (8-14) were synthesized from the cyclization of chalcone compounds (1-7) containing different functional groups with hydroxylamine hydrochloride in alkaline medium. Tyrosinase and antioxidant properties of 8-14 were investigated. IC50 values for the tyrosinase enzyme inhibition of compounds 8, 11, 12, and 13 were varied between 61.47 ± 3.46 and 188.52 ± 5.85, while compounds 9, 10 and 14 did not show any inhibition effect. The antioxidant properties of 8-14 were investigated by DPPH and CUPRAC methods. Compound 12 showed the best DPPH radical scavenging activity (SC50: 40.21 ± 2.71), while 12 and 13 …


Removal Of Cd2+ Metal Ions From Aqueous Solutions By Na-Alginate-Containingcomposite Biosorbent, Ramazan Donat Jan 2022

Removal Of Cd2+ Metal Ions From Aqueous Solutions By Na-Alginate-Containingcomposite Biosorbent, Ramazan Donat

Turkish Journal of Chemistry

This research is related to the effect of alginate-containing composite biosorbent on the sorption capacity of heavy metal Cd2+ ions. The study aims to determine the character and optimization of the sorption of Na-alginate-containing composite biosorbent on the sorption of heavy metal Cd2+ metal ions in an aqueous solution. Optimum conditions of parameters such as biosorbent amount, pH value effect, concentration effect, contact time, and temperature that affect the sorption of Cd2+ ions were determined. Langmuir, Freundlich, D-R isotherms were applied to the obtained data, and it was noted that the sorption Cd2+ ions are better explained with Freundlich and …


Synthesis Of 2-Aryl-5-(Arylsulfonyl)-1,3,4-Oxadiazoles As Potent Antibacterial Andantioxidant Agents, S N Murthy Boddapati, Subrahmanyam Talari, A Emmanuel Kola, Bhuvaneswari Chalapaka Jan 2022

Synthesis Of 2-Aryl-5-(Arylsulfonyl)-1,3,4-Oxadiazoles As Potent Antibacterial Andantioxidant Agents, S N Murthy Boddapati, Subrahmanyam Talari, A Emmanuel Kola, Bhuvaneswari Chalapaka

Turkish Journal of Chemistry

Ten novel 2-aryl-5-(arylsulfonyl)-1,3,4-oxadiazoles were produced and assessed for their in vitro antibacterial and antioxidant activities. Diverse spectroscopic methods li1H NMR, 13C NMR, IR, and LCMS were used for the characterization of the prepared samples and all the data was in good agreement with the anticipated structures. The prepared compounds 6a-j were screened for their in vitro antibacterial activity against bacterial strains Pseudomonas aeruginosa, Enterobacter aerogenes, Escherichia coli (grampositive), and Bacillus cerus, Staphylococcus aureus, Bacillus subtilis (gram-negative). The antimicrobial screening outcome revealed that the prepared 2-(3,4-dimethylphenyl)-5-tosyl-1,3,4-oxadiazole (6j), 2-(3-isopropylphenyl)-5-tosyl-1,3,4-oxadiazole (6c), and 2-(2-ethylphenyl)-5-tosyl-1,3,4-oxadiazole (6i) are most potent among all the examined compounds. Furthermore, …


Ultrafiltration-Based Sample Preparation And Hplc-Uv Determination Of Diclofenac In Human Plasma Samples, Merve Nenni̇, Ayşegül Doğan, Mustafa Çelebi̇er, Murat Soyseven, Mustafa Si̇nan Kaynak, Hassan Y. Aboul-Enein, Göksel Arli̇ Jan 2022

Ultrafiltration-Based Sample Preparation And Hplc-Uv Determination Of Diclofenac In Human Plasma Samples, Merve Nenni̇, Ayşegül Doğan, Mustafa Çelebi̇er, Murat Soyseven, Mustafa Si̇nan Kaynak, Hassan Y. Aboul-Enein, Göksel Arli̇

Turkish Journal of Chemistry

The sample preparation step is the initial step in pharmaceutical analysis. While ultrafiltration is a well-known technique used in the food and pharmaceutical industries, it has rarely been used to measure the plasma concentration of active pharmaceutical ingredients. This study aimed to analyze diclofenac sodium (DS) in human plasma samples using ultrafiltration-based sample preparation before high-performance liquid chromatography (HPLC) analysis. The advantages and limitations of ultrafiltration-based sample preparation in bioanalysis were evaluated by comparing the results with conventional methods. The precipitating agent was used before ultrafiltration. The analysis was carried on an HPLC-UV system with a C18 column (250 ×4.6 …


Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut Jan 2022

Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut

Turkish Journal of Chemistry

In this paper, we have prepared peripherally tetra-({6-[3-(diethylamino)phenoxy]hexyl}oxy substituted cobalt(II), copper(II), manganese(III) phthalocyanines (3, 4, 5) and their water-soluble derivatives (3a, 4a, 5a). Then, in vitro α-glucosidase and cholinesterases inhibitory actions of the water-soluble 3a, 4a, 5a were examined using spectrophotometric methods. 4a had the highest inhibitory effects among the tested compounds against α-glucosidase due to IC50 values. 4a and 5a had 40 fold higher inhibitory effects than the positive control. For cholinesterases, the compounds showed significant inhibitory actions that of galantamine which was used as a positive control. According to the SI value, 3a inhibited acetylcholinesterase enzyme selectively. In …


Induction Of Lutein Production In Scenedesmus Obliquusunder Different Culture Conditions Prior To Its Semipreparative Isolation, Ayşegül Erdoğan, Ayça Büşra Karataş, Zeli̇ha Demi̇rel, Meltem Dalay Jan 2022

Induction Of Lutein Production In Scenedesmus Obliquusunder Different Culture Conditions Prior To Its Semipreparative Isolation, Ayşegül Erdoğan, Ayça Büşra Karataş, Zeli̇ha Demi̇rel, Meltem Dalay

Turkish Journal of Chemistry

Microalgae with their improved growth rates and accumulation of high-value-added products make their commercial production attractive. Among them, lutein, which is a carotenoid, plays a very important role due to its various applications in the food and pharmaceutical industry. Induction of its biosynthesis can be triggered by various stress conditions like light. In this study, three different light intensities (50,150 and 300 μmol photons/m2s) and aeration rates (1, 3, and 5 L/min) were utilized to induce the lutein biosynthesis and biomass productivity in Scenedesmus obliquus. Lutein was isolated by preparative chromatography using a semiprep C30 column (10 × 250 mm, …


Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi Jan 2022

Drug Delivery System For Controlled Release Of Empagliflozin From Alginate-Chitosannanocarrier System, Nasim Ramazanzadeh, Nosrat O. Mahmoodi

Turkish Journal of Chemistry

biocompatible nanocarrier system was prepared in this research through the reaction of calcium alginate (CA) with chitosan (CS). The structure of developed nanocarriers (CS-CA) was characterized by thermogravimetric analysis (TGA), Fourier transforms infrared (FT-IR) spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) atomic force microscopy (AFM), and transmission electron microscopy (TEM). Swelling properties of CS-CA and CA, and their ability for loading and in vitro release of empagliflozin (EMP) were also investigated. The results showed the higher loading capacity of CS-CA compared to CA. For both nanocarriers, the drug release was higher at neutral pH (7.4 and 6.8) …


Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia Jan 2022

Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia

Turkish Journal of Chemistry

In this study, ferrihydrite/ultrasound (US) system was used to activate peroxymonosulfate (PMS) to treat humic acid (HA) in artificial aqueous. The physical and chemical properties of ferrihydrite were characterized using SEM, zeta potential, BET, XRD, FTIR, and XPS analysis. A series of experiments were conducted to evaluate the effect of various factor on HA removal, including dosage of ferrihydrite, PMS concentration and pH value. The combination uses of US and ferrihydrite had obvious synergistic effect for HA removal. Under ferrihydrite/US/PMS system, nonthermal effect of US played the main role for HA removal. According to the result of radical quenching experiment, …


A New Study Of Dynamic Mechanical Analysis And The Microstructure Of Polyurethanefoams Filled, Noureddine Boumdouha, Zitouni Safidine, Achraf Boudiaf Jan 2022

A New Study Of Dynamic Mechanical Analysis And The Microstructure Of Polyurethanefoams Filled, Noureddine Boumdouha, Zitouni Safidine, Achraf Boudiaf

Turkish Journal of Chemistry

Polyurethane foams have good shock-absorbing properties. This article discusses the study of the physical, dynamic analysis, and microstructure of filled polyurethane foams (PUR). We used mineral fillings nanoparticles of titanium dioxide (TiO2) and calcium carbonate (C1) to support and strengthen the foam cell structure to develop shock absorption and thermal resistance properties. Dynamic mechanical analysis (DMA) and compression tests compared the mechanic characterization results with different modelling approaches. For studies of physicochemical properties, we used differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). We deduced the flame retardancy mechanism. It appears that a detailed description of the characteristics of viscosity …


Design, Synthesis, And In Vitro Antitumor Activity Of 6-Aryloxyl Substituted Quinazolinederivatives, Meixia Fan, Lei Yao Jan 2022

Design, Synthesis, And In Vitro Antitumor Activity Of 6-Aryloxyl Substituted Quinazolinederivatives, Meixia Fan, Lei Yao

Turkish Journal of Chemistry

Quinazoline derivatives are a class of important antitumor drugs known as small molecule inhibitors that include epidermal growth factor receptor (EGFR) inhibitors. Based on the structure of poziotinib, a series of 6-aryloxyl substituted quinazoline derivatives were designed and synthesized. The in vitro antitumor activities of the compounds were evaluated by the 3-(4,5-dimethyl-thiazol-2- yl)2,5-diphenyltetrazolium bromide (MTT) method using the human gastric cancer N87 (HER2), nonsmall-cell lung cancer H1975 (EGFRT790M/L858R), and A549 (EGFRWT) cell lines. The most promising compound 4m exhibited potent antitumoral activities with IC50 values of 6.3 nM and 7.5 nM for N87 and H1975 cell lines, respectively. Meanwhile, it …


Adsorption Of Dimethyl Disulfide Onto Activated Carbon Cloth, Fi̇rdevs Mert, Numan Hoda, Ayhan Topuz, Leyla Budama Akpolat, Emrah Eroğlu Jan 2022

Adsorption Of Dimethyl Disulfide Onto Activated Carbon Cloth, Fi̇rdevs Mert, Numan Hoda, Ayhan Topuz, Leyla Budama Akpolat, Emrah Eroğlu

Turkish Journal of Chemistry

Dimethyl disulfide (DMDS) has a specific unpleasant odour and is profoundly toxic with an odour threshold of around 7-12 ppb. In this study, the removal of DMDS was investigated by adsorption on activated carbon cloth (ACC) in the gas phase. Kinetics and isotherm studies were performed. Adsorption kinetics followed by GC-MS and the data were processed using different models. When correlation coefficients (R2) of linear regression analysis are analyzed, it is seen that the concordance of experimental data to the pseudo-second-order equation is quite good. Isotherm data have been examined using Freundlich, Temkin and Langmuir models. The regression coefficient (R2) …


Electroanalytical Investigation And Voltammetric Quantification Of Antiviral Drug Favipiravir In The Pharmaceutical Formulation And Urine Sample Using A Glassy Carbon Electrode In Anionic Surfactant Media, Zeynep Akca, Hande İzem Özok, Yavuz Yardim, Zühre Şentürk Jan 2022

Electroanalytical Investigation And Voltammetric Quantification Of Antiviral Drug Favipiravir In The Pharmaceutical Formulation And Urine Sample Using A Glassy Carbon Electrode In Anionic Surfactant Media, Zeynep Akca, Hande İzem Özok, Yavuz Yardim, Zühre Şentürk

Turkish Journal of Chemistry

This work describes the electrochemical investigation of a promising antiviral agent, favipiravir (FAV) utilizing a nonmodified glassy carbon (GC) electrode, along with a unique voltammetric approach that can determine FAV with a good degree of accuracy, speed, and cost-effectiveness. Using cyclic voltammetry, the compound demonstrated a single well-defined and an irreversible oxidation peak at approximately +1.12 V (vs. Ag/AgCl) in Britton-Robinson (BR) buffer at pH 10.0. The synergistic effect of anionic surfactant, sodium dodecyl sulfate (SDS) on the adsorption ability of GC electrode remarkably increased the sensitivity of the stripping voltammetric measurements of FAV. Employing square-wave adsorptive stripping voltammetry at …


Parametric And Kinetic Study Of Solvent-Free Synthesis Of Solketal Using Ion Exchange Resin, Dheer A. Rambhia, Sravanthi Veluturla, Archna Narula Jan 2022

Parametric And Kinetic Study Of Solvent-Free Synthesis Of Solketal Using Ion Exchange Resin, Dheer A. Rambhia, Sravanthi Veluturla, Archna Narula

Turkish Journal of Chemistry

The ketalization reaction of glycerol with acetone for solketal formation was performed using a gel-type ion exchange resin, Indion 225H in a solvent-free medium. The experimental parameters molar ratio, catalyst loading, rate of stirring, and temperature were analyzed and evaluated for their impact on the conversion of glycerol. A kinetic model based on the Langmuir-Hinshelwood?Hougen- Watson (LHHW) equation described the kinetics of the heterogeneous system. The parameters were evaluated using the ode45 solver and Genetic Algorithm (GA) optimization function on MATLAB software. The activation energy for the ketalization of glycerol was found to be 39.3 kJ/mol, the enthalpy of adsorption …


Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz Jan 2022

Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz

Turkish Journal of Chemistry

Several 5-(alkylsulfonyl)-1-substituted-2-(1H-pyrrol-2-yl)-1H-benzo[d]imidazole derivatives were synthesized and their antioxidant activities were investigated using lipid peroxidation (LPO) and 7-ethoxyresorufin O-deethylase (EROD) assays. Docking analysis with Human NAD[P]H-Quinone oxidoreductase 1 (NQO1) was also performed to gather thorough information about these compounds that have antioxidant activities. Moreover, their molecular descriptors and ADME properties were calculated using the SwissADME online program. As a result, most of our compounds possessed better affinity and created ample interactions with NQO1. The most potent compound 5j had LP inhibition value of 3.73 nmol/mg/min. Other compounds exhibited moderate activity on LP levels comparing to standard butylated hydroxy toluene (BHT). However, …


Microwave-Assisted Rapid Conjugation Of Horseradish Peroxidase-Dextran Aldehyde With Schiff Base Reaction And Decolorization Of Reactive Blue 19, Mi̇that Çelebi̇, Zafer Ömer Özdemi̇r, Murat Topuzoğullari Jan 2022

Microwave-Assisted Rapid Conjugation Of Horseradish Peroxidase-Dextran Aldehyde With Schiff Base Reaction And Decolorization Of Reactive Blue 19, Mi̇that Çelebi̇, Zafer Ömer Özdemi̇r, Murat Topuzoğullari

Turkish Journal of Chemistry

Microwave irradiation has become a routine technique in homogeneous and effective heating in organic synthesis. However, its application in enzyme-containing reactions is limited since it can cause denaturation of the enzyme. In this study, we have briefly investigated the effect of microwave heating on the conjugation reaction of horseradish peroxidase (HRP) with aldehyde derivative of dextran (D-CHO). The reaction was irradiated by microwave at 50 °C for 5 min. The conjugate was confirmed via GPC, in which the conjugates of HRP and D-CHO coexist with free unbound HRP molecules. Activity studies of HRP revealed that there is a small decrease …


Microstructure And Ionic Conductivity Investigation Of Samarium Doped Ceria(Sm0.2ce0.8o1.9) Electrolytes Prepared By The Templating Methods, Di̇lara Güçtaş, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer Jan 2022

Microstructure And Ionic Conductivity Investigation Of Samarium Doped Ceria(Sm0.2ce0.8o1.9) Electrolytes Prepared By The Templating Methods, Di̇lara Güçtaş, Vedat Sariboğa, Mehmet Ali̇ Faruk Öksüzömer

Turkish Journal of Chemistry

Sm0.2Ce0.8O1.9 (SDC20) electrolytes were synthesized with cellulose templating (CT) and PVA templating (PVAT) methods. Powder characteristics were examined using TG/DTA, XRD, and SEM. Pellets are sintered at various temperatures for different durations. Mean grain sizes were calculated from SEM micrographs using the linear intercept method. Grain growth behavior of the electrolytes was investigated and the dominant diffusion mechanism was examined. The grain growth activation energies were obtained for the first time for the mentioned electrolytes prepared by the mentioned methods. The ionic conductivities were calculated by electrochemical impedance spectroscopy. The highest ionic conductivity value was found to be 0.050 S …


Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan Jan 2022

Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan

Turkish Journal of Chemistry

A new RP-HPLC method was developed and validated to achieve the separation and quantification of the organic explosive compounds such as pentaerythritol tetranitrate (PETN), 1-methyl-2,4,6-trinitro toluen (TNT), picric acid, 1,3,5,7-tetrazocine (HMX), cyclorimethylenetrinitramine (RDX), 2,4,6 Tri nitro phenyl methyl nitramine (Tetryl), 1-methyl-2,4-dinitro toluen (DNT), ethylene glycol dinitrate (EGDN), and trinitroglycerine (TNG) in this study. The mobile phase composition (IPA percentage in water) and the flow rate was optimized for the separation of the organic explosive compounds. Theoretical plate number (N), capacity factor (k'), resolution (Rs) were used to determine the optimum chromatographic conditions. The most favorable conditions were detected as 22% …


Boric Acid And Schiff Base-Based Fluorescent Sensor For Detection Of L-Tryptophan In Milk And Bsa Samples, Ümran Duru Kamaci, Musa Kamaci Jan 2022

Boric Acid And Schiff Base-Based Fluorescent Sensor For Detection Of L-Tryptophan In Milk And Bsa Samples, Ümran Duru Kamaci, Musa Kamaci

Turkish Journal of Chemistry

In the present paper, the fluorescence sensor based on Schiff base and boric acid was developed for easy and rapid detection of L-tryptophan in different samples such as milk and bovine serum albumin. The photoluminescence intensity was measured by using fluorescent measurements and the results indicated that the developed fluorescent sensor was exhibited selective, sensitive, reliable determination against L-tryptophan, and a series of various analytes such as cations, amino acids, and organic compounds were used to investigate the selectivity of the fluorescent chemosensor. The limit of detection and linear range of the chemosensor were calculated as 0.82 μM, and 0.1?500 …


Effect Of Promoter Type And Synthesis Method On Catalytic Performance Of Fe-Mn Based Ft-Olefin Catalysts, Gamze Gümüşlü Gür, Özge Ati̇k Jan 2022

Effect Of Promoter Type And Synthesis Method On Catalytic Performance Of Fe-Mn Based Ft-Olefin Catalysts, Gamze Gümüşlü Gür, Özge Ati̇k

Turkish Journal of Chemistry

Direct production of light olefins, building blocks of chemical industry, can be attained by developing efficient catalysts for Fischer?Tropsch synthesis (FTS). The nature of FTS complicates the catalyst development process as the product distribution is affected by the components and the preparation methods of the catalyst. In this work, high-throughput (HT) methodology is employed to overcome this problem by testing many different catalyst formulations. Fast performance screening of 40 different α-Al2O3 supported Fe-Mn based catalysts promoted with Cu, K and Ni, using different impregnation agents, was performed in a HT test system at atmospheric pressure. Promising catalyst candidates identified by …


Quantifying Time-Dependent Structural And Mechanical Properties Of Uv-Aged Ldpe Power Cables Insulations, Abdallah Hedir, Ferhat Slimani, Mustapha Moudoud, Omar Lamrous, Tahar Touam, Madjid Teguar, Abderrahmane Haddad, Ali̇ Durmuş Jan 2022

Quantifying Time-Dependent Structural And Mechanical Properties Of Uv-Aged Ldpe Power Cables Insulations, Abdallah Hedir, Ferhat Slimani, Mustapha Moudoud, Omar Lamrous, Tahar Touam, Madjid Teguar, Abderrahmane Haddad, Ali̇ Durmuş

Turkish Journal of Chemistry

This paper reports effects of ultraviolet (UV) light radiation on the physicochemical, electrical and mechanical properties of low-density polyethylene (LDPE) cable insulating materials. Changes in structural and morphological properties of UV-aged samples were characterized by various analytical methods such as attenuated total reflection Fourier transform infrared spectroscopy (ATRFTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Additionally, elongation at break, tensile strength, dielectric strength, and optical properties were also evaluated. Changes in some physical properties of LDPE after exposing to UV irradiation clearly highlighted that the polymer underwent the structural degradation. In addition, it was also …


Electrically Conductive, Hydrophobic, Uv Protective And Lightweight Cotton Spunlace Nonwoven Fabric Coated With Reduced Graphene Oxide, Beki̇r Cenkkut Gülteki̇n Jan 2022

Electrically Conductive, Hydrophobic, Uv Protective And Lightweight Cotton Spunlace Nonwoven Fabric Coated With Reduced Graphene Oxide, Beki̇r Cenkkut Gülteki̇n

Turkish Journal of Chemistry

In this study, cotton spunlace nonwoven fabrics with four different basis weights were coated with graphene oxide (GO) by conventional dip coating method which is one of the most simple and effortless process in textile industry. The graphene oxide coated cotton nonwoven fabrics were immersed in an aqueous sodium dithionite solution in order to obtain reduced graphene oxide (RGO) coated cotton spunlace nonwoven fabrics. The obtained nonwoven fabrics became electrically conductive with very low surface electrical resistivity of 5.98 × 102 W/sq for the 70 g/m2 basis weight nonwoven fabric. The color measurements and reflectance spectrophotometry were performed in order …


Synthesis And Characterization Of Amino Sulfonic Acid Functionalized Graphene Oxide As A Potential Carrier For Quercetin, Ali Sadeghi, Mohammad Faeli, Mahmood Tajbakhsh, Abdolreza Abri, Monireh Golpour Jan 2022

Synthesis And Characterization Of Amino Sulfonic Acid Functionalized Graphene Oxide As A Potential Carrier For Quercetin, Ali Sadeghi, Mohammad Faeli, Mahmood Tajbakhsh, Abdolreza Abri, Monireh Golpour

Turkish Journal of Chemistry

In this investigation, a new nanocomposite as a nanocarrier based on functionalized graphene oxide was synthesized by reaction of tetraethylenepentamine and chlorosulfonic acid with functional groups on the surface of GO. The synthesized nanocomposite was characterized by FT-IR, XRD TGA, FE-SEM, EDAX, TEM, and AFM analysis. To explore the potential of nanocomposites in drug delivery, the loading and releases of quercetin as an anticancer drug were investigated. The result displayed that more than 90% of the drug was loaded on the nanocarrier and the release of the drug is depending on the pH of the environment such that the releases …


Co2 Absorption Into Primary And Secondary Amine Aqueous Solutions With And Without Copper Ions In A Bubble Column, Hamed Yousefzadeh, Cansu Güler, Can Erkey, Erdal Uzunlar Jan 2022

Co2 Absorption Into Primary And Secondary Amine Aqueous Solutions With And Without Copper Ions In A Bubble Column, Hamed Yousefzadeh, Cansu Güler, Can Erkey, Erdal Uzunlar

Turkish Journal of Chemistry

Chemical absorption of CO2 into aqueous amine solutions using a nonstirred bubble column was experimentally investigated. The performance of CO2 absorption of four different primary and secondary amines including monoethanolamine (MEA), piperazine (PZ), 2-piperidineethanol (2PE), and homopiperazine (HPZ) were compared. The effects of initial concentration of amine, the inlet mole fraction of CO2, and solution temperature on the rate of CO2 absorption and CO2 loading (mol CO2/mol amine) were studied in the range of 0.02-1 M, 0.10-0.15, and 25-40 °C, respectively. The effect of the presence of copper ions in the amine solution on CO2 loading was also studied. By …


Peg4000 Modified Liposomes Enhance The Solubility Of Quercetin And Improve The Liposome Functionality: In Vitro Characterization And The Cellular Efficacy, Gülen Meli̇ke Demi̇rbolat, Ömer Erdoğan, Gökni̇l Peli̇n Coşkun, Özge Çevi̇k Jan 2022

Peg4000 Modified Liposomes Enhance The Solubility Of Quercetin And Improve The Liposome Functionality: In Vitro Characterization And The Cellular Efficacy, Gülen Meli̇ke Demi̇rbolat, Ömer Erdoğan, Gökni̇l Peli̇n Coşkun, Özge Çevi̇k

Turkish Journal of Chemistry

Quercetin, a multifunctional therapeutic agent, is used in various types of cancer. However, its therapeutic effect is limited by virtue of poorly aqueous solubility and instability in the physiological medium. To overcome these limitations, we aimed (i) to design quercetin loaded liposomes with unlinked-PEG4000 with regard to not only surface modification but also solubility enhancement, and (ii) to investigate the antineoplastic effects on HeLa cells. PEG4000 increased the quercetin solubility 2.2 fold. PEG4000 modified liposomes displayed small particle size (254 ± 69 nm), low polydispersity index (0.236 ± 0.018), favorable zeta potential (-35.4 ± 0.6 mV), high quercetin encapsulation efficiency …


Synthesis Of Polydentate, Multi Metal Ion Sensing, Unsymmetrical Schiff Bases With Complimented Antifungal Activity, Saranya Dhasarathan, Selvaraj Shunmugaperumal, P. Kamatchi Selvaraj Jan 2022

Synthesis Of Polydentate, Multi Metal Ion Sensing, Unsymmetrical Schiff Bases With Complimented Antifungal Activity, Saranya Dhasarathan, Selvaraj Shunmugaperumal, P. Kamatchi Selvaraj

Turkish Journal of Chemistry

Polydentate, unsymmetrical, and multi metal ion sensing Schiff bases comprised of ferrocenecarboxaldehyde attached azomethine group at one side and aromatic aldehyde linked imine on the other side have been synthesized. Cumulative addition of different metal salts solution to receptors solution, changes the electronic spectra contrarily and for the addition of Cu2+ ions, generation of MLCT charge transfer band responsible for the coordination of metal ion with a receptor is observed. Electrochemical data (ΔEp) arrived from the cyclic voltammograms suggest a quasi-reversible process. The modest concentration of metal ions required for effective sensing by the sensory material is calculated from the …


Intake Of Divalent Copper And Nickel Onto Natural Zeolite From Aqueous Solutions: A Study In Mono- And Dicomponent Systems, Burak Teki̇n, Ünsal Açikel Jan 2022

Intake Of Divalent Copper And Nickel Onto Natural Zeolite From Aqueous Solutions: A Study In Mono- And Dicomponent Systems, Burak Teki̇n, Ünsal Açikel

Turkish Journal of Chemistry

In this study, the noncompetitive and competitive adsorption process of copper (II) and nickel (II) ions on the natural zeolite were examined in simulated wastewater in a batch system with respect to concentration, pH and temperature. Optimum pH values were found as 5,0 for adsorption of copper and nickel ions on the zeolite. The effect of initial concentration and ambient temperature on the yield of adsorption was examined at this pH value. The equilibrium adsorption data of Cu (II) and Ni (II) onto the zeolite were analyzed by the Langmuir's and Freundlich's isotherms, and the experimental metal uptake data fitted …


Thio-Schiff Bases Derived From 2,2'-Disulfanedianiline Via Nanocerium Oxide: Antimicrobial Effect And Antiproliferative Effects In Melanoma Cells, Aslihan Dalmaz, Sefa Durmuş, Görkem Dülger, Merve Alpay Jan 2022

Thio-Schiff Bases Derived From 2,2'-Disulfanedianiline Via Nanocerium Oxide: Antimicrobial Effect And Antiproliferative Effects In Melanoma Cells, Aslihan Dalmaz, Sefa Durmuş, Görkem Dülger, Merve Alpay

Turkish Journal of Chemistry

In this study, the synthesis of dimeric disulfide-Schiff bases was carried out using two methods. The structures of the obtained Schiff bases were elucidated by various spectroscopic methods as well as elemental analysis. The Schiff base derivative compounds (3a-6) were screened for in vitro antibacterial activity against multidrug-resistant microorganisms using microdilution method. All the tested compounds showed varying inhibition zones against the pathogens. According to MIC results, the compound 2 was shown strong inhibitory activity against all the tested microorganisms compared to antibiotics. In addition, all the tested compounds showed different antiproliferative effects on the melanoma cell line (B16F10). Our …


Comparison Of A Commercial Water-Gas Shift Catalyst And La Modified Cu-Based Catalysts Prepared By Deposition-Precipitation In Methanol Steam Reforming, Orhan Özcan, Ayşe Ni̇lgün Akin Jan 2022

Comparison Of A Commercial Water-Gas Shift Catalyst And La Modified Cu-Based Catalysts Prepared By Deposition-Precipitation In Methanol Steam Reforming, Orhan Özcan, Ayşe Ni̇lgün Akin

Turkish Journal of Chemistry

Herein, a performance analysis of La-doped copper-based catalysts (CuO/ZrO2/La-Al2O3) in methanol steam reforming (MSR) was conducted and compared with a commercial low temperature water-gas shift catalyst (HiFUEL W220) to produce H2 with low CO selectivity. The physicochemical properties of as-obtained catalysts were characterized by N2 adsorption, XRD, and ICP-OES. Effect of calcination temperature (750 oC and 1000 oC) on the properties of mixed oxide support (La-Al2O3) were discussed based on catalytic activity. The optimum conditions of H23O/CH3OH ratio (1.0-3.0), space-time ratio (WFA0) (40-120 kg s mol-1), and reaction temperature (180-310 oC) were evaluated by a parametric study using the commercial …


Oxygen Vacancies On Pd/Tio2 Are Detected At Low Pressures By Esr Spectroscopy At Ambient Temperatures, Deni̇z Üner, Meli̇s Yarar Jan 2022

Oxygen Vacancies On Pd/Tio2 Are Detected At Low Pressures By Esr Spectroscopy At Ambient Temperatures, Deni̇z Üner, Meli̇s Yarar

Turkish Journal of Chemistry

A low field benchtop electron spin resonance (ESR) (also referred to as electron paramagnetic resonance (EPR)) spectrometer is used to reveal paramagnetic centres such as oxygen vacancies and Ti+3 centres over 0.5%Pd/TiO2. The measurement was performed at room temperature after the sample was reduced in situ under mild hydrogen pressures and evacuated to P < 10-6 Torr. The measurement was possible due to a T1 compensation effect under vacuum: Correlation times at low pressures enabled sufficient line narrowing and detection of the ESR signal, justifying a method using benchtop spectrometers coupled to vacuum manifolds. The method justification was demonstrated using similar measurements performed on a reference compound, Mn(II) in plasticine: a measurement performed by saturation recovery technique revealed that T1 of the signal due to Mn(II) was smaller in vacuum than its atmosphere exposed counterpart. By applying vacuum, the ESR spectra of 0.5%Pd/TiO2 were collected at ambient temperatures, with features equivalent to the published data obtained at cryogenic temperatures.


Synthesis Of Novel Oxadiazole Derivatives And Their Cytotoxic Activity Against Various Cancer Cell Lines, Bi̇lgesu Onur Sucu, Eli̇f Beyza Koç Jan 2022

Synthesis Of Novel Oxadiazole Derivatives And Their Cytotoxic Activity Against Various Cancer Cell Lines, Bi̇lgesu Onur Sucu, Eli̇f Beyza Koç

Turkish Journal of Chemistry

Caffeic acid (CA), ferulic acid (FA) and caffeic acid phenethyl ester (CAPE) have a broad anticancer effect on various cell lines. In this study, nine ferulic and caffeic acid-based 1,2,4 and 1,3,4 oxadiazole molecular hybrids were synthesized and their cytotoxic activity was evaluated mainly against Glioblastoma (GBM) cell lines. Compounds 1 and 5 exhibited the highest inhibitory activity against three different GBM cell lines (LN229, T98G, and U87), without toxicity to healthy human mesenchymal stem cells (hMSC). In addition, their cytotoxicity was also evaluated against three additional cancer cell lines and more inhibitory results were found than GBM cell lines. …