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Full-Text Articles in Physical Sciences and Mathematics
Folic Acid-Targeted Polymeric Complex Imprinted With Doxorubicin And Quercetin For Controlled Drug Delivery In Cancer Therapy, Ceren Türkcan, Emi̇rhan İşeri̇
Folic Acid-Targeted Polymeric Complex Imprinted With Doxorubicin And Quercetin For Controlled Drug Delivery In Cancer Therapy, Ceren Türkcan, Emi̇rhan İşeri̇
Turkish Journal of Chemistry
Cancer therapy is often limited by the systemic toxicity and dose-dependent adverse effects of conventional chemotherapeutic agents such as doxorubicin (DOX). In this study, a folic acid-functionalized molecularly imprinted polymeric complex based on poly(HEMA) crosslinked with ethylene glycol dimethacrylate was synthesized for the controlled release of DOX in combination with quercetin (QUE), a flavonoid known for its antioxidant and chemosensitizing properties. The aim of this work was to develop and physicochemically characterize a preliminary targeted drug delivery platform at a material-design level. The polymeric complex was synthesized via free-radical polymerization following a DOX–QUE precomplex formation step. Structural characterization was performed …
A Poly-L-Lysine-Functionalized Electrochemical Immunosensor Enables Highly Sensitive Detection Of Tumor Necrosis Factor Receptor-Associated Protein 1, Berfi̇n Vural, Mustafa Kemal Sezgi̇ntürk
A Poly-L-Lysine-Functionalized Electrochemical Immunosensor Enables Highly Sensitive Detection Of Tumor Necrosis Factor Receptor-Associated Protein 1, Berfi̇n Vural, Mustafa Kemal Sezgi̇ntürk
Turkish Journal of Chemistry
Tumor necrosis factor receptor-associated protein 1 (TRAP-1), a member of the mitochondrial heat shock protein family (HSP90), is essential for protein homeostasis, stress response, and cell cycle. TRAP-1 not only optimizes cellular energy production but also prevents cell death, thereby supporting the survival and proliferation of tumor cells. In addition to cancer, TRAP-1 has been associated with Parkinson’s disease, certain autoimmune disorders, and abnormalities in the kidney and urinary tract. In this study, a unique and useful indium tin oxide-polyethylene terephthalate (ITO–PET)-based electrochemical biosensor is described for detecting the biomarker TRAP-1. The ITO–PET electrode, selected as the working electrode, is …
Aptamer–Gold Nanoparticle-Based Lab-In-A-Tube Colorimetric Detection Of Malathion: Evaluation With Classical And Digital Readout Techniques, Emi̇ne Güler Çeli̇k
Aptamer–Gold Nanoparticle-Based Lab-In-A-Tube Colorimetric Detection Of Malathion: Evaluation With Classical And Digital Readout Techniques, Emi̇ne Güler Çeli̇k
Turkish Journal of Chemistry
Colorimetric biosensing devices represent an important class of point-of-care (POC) diagnostics due to their ability to provide visible test outputs, their ease of integration with smartphone-based sensing, and their portability for field testing. In the context of agrifood safety, there is a growing need for portable, robust, and cost-effective detection devices. Pesticide residues can be present in a wide range of environmental and food samples, from water resources to fruits and vegetables, resulting in an increasing global demand for on-site testing. Colorimetric assays, when combined with smartphone-based sensing, can effectively address these needs. In this work, the aggregation-induced color change …
Sensitive Electrochemical Sensor For Simultaneous Determination Of Epinephrine And Norepinephrine By Sio2np@Mwcnt-Cooh Nanoparticle-Modified Spces, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç, Ayşenur Yilmaz Kabaca, Şahi̇n Toparli, Faruk Terzi̇oğlu, Emi̇r Ateş
Sensitive Electrochemical Sensor For Simultaneous Determination Of Epinephrine And Norepinephrine By Sio2np@Mwcnt-Cooh Nanoparticle-Modified Spces, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç, Ayşenur Yilmaz Kabaca, Şahi̇n Toparli, Faruk Terzi̇oğlu, Emi̇r Ateş
Turkish Journal of Chemistry
Epinephrine (EP) and norepinephrine (NEP), both neurotransmitters, are two important biomolecules that play critical roles in the body, from the central nervous system to metabolic processes. They are also important biomarkers for clinical diagnosis and monitoring. In this study, a novel, fast, practical, and high-performance electrochemical sensor based on a SiO2NP@MWCNT-COOH nanocomposite was developed for the simultaneous determination of EP and NEP. The nanocomposite was modified onto the surface of screen-printed electrodes (SPCEs) and its characterization was performed (SEM-EDX, XRD, FTIR, CV, DPV, and EIS). The individual and simultaneous determinations of EP and NEP were performed using square-wave voltammetry, yielding …
Acetylcholinesterase Immobilization On A Natural Thin Membrane For Stable Biocatalyst Design, Si̇nem Öztürk, Ceyhun Işik, Mustafa Teke
Acetylcholinesterase Immobilization On A Natural Thin Membrane For Stable Biocatalyst Design, Si̇nem Öztürk, Ceyhun Işik, Mustafa Teke
Turkish Journal of Chemistry
This study involved the immobilization of acetylcholinesterase (AChE) onto a natural thin membrane extracted from the inner epidermal layer of Allium cepa, with the aim of enhancing the enzyme’s stability, activity, and reusability for potential biotechnological applications. The membrane, composed of biocompatible polymers and naturally occurring functional groups, was used as a sustainable support in a combined strategy involving adsorption followed by glutaraldehyde-mediated cross-linking. Immobilization conditions were optimized by evaluating key factors such as enzyme concentration, membrane quantity, cross-linker dosage, and contact time to achieve maximal catalytic efficiency. Structural and morphological changes on the membrane surface were assessed via scanning …
Antifungal Activity Of Isolated Compounds From Centaurea Salicifolia Var. Salicifolia Against Candida Species, Including Multidrug-Resistant C. Auris, C. Inconspicua, And C. Dubliniensis, Seli̇n Tufan, Di̇lek Şatana, Nur Tan
Antifungal Activity Of Isolated Compounds From Centaurea Salicifolia Var. Salicifolia Against Candida Species, Including Multidrug-Resistant C. Auris, C. Inconspicua, And C. Dubliniensis, Seli̇n Tufan, Di̇lek Şatana, Nur Tan
Turkish Journal of Chemistry
Natural compounds obtained from plants have always held great potential for drug discovery and, as such, have drawn the attention of researchers as novel antifungal molecules that can be effective against fungal resistance. The antifungal activity of sesquiterpene lactones has been extensively investigated against various fungal strains, but there is limited data on their antifungal activity against Candida species. Sesquiterpene lactones are abundant in the Asteraceae family, and 90% of identified sesquiterpene lactones have been isolated from members of this family. Three extracts obtained from the aerial parts of Centaurea salicifolia var. salicifolia, which had not been investigated prior to …
Electrochemical Determination Of Terbutaline Using A Sno2 Nanoparticle-Modified Carbon Paste Electrode, Rauf Gulamov, Şenol Alpat, Si̇bel Kilinç Alpat
Electrochemical Determination Of Terbutaline Using A Sno2 Nanoparticle-Modified Carbon Paste Electrode, Rauf Gulamov, Şenol Alpat, Si̇bel Kilinç Alpat
Turkish Journal of Chemistry
Terbutaline hemisulfate (THS), a selective beta-2 agonist, is preferred as a bronchodilator for the treatment of asthma and bronchitis, as well as a tocolytic agent to delay labor in acute situations during premature birth. The use of beta-2 agonists above a certain dose is considered doping in sports competitions. Therefore, it is important that they be determined with high sensitivity and selectivity within a short analysis time. In this study, a SnO2 nanoparticle-modified carbon paste electrode was developed for the determination of THS. Cyclic voltammetry and differential pulse voltammetry were employed as electrochemical methods. The operating conditions of the developed …
Chitosan Microparticle-Based Antibacterial Nasal Barrier Formulation And In Vivo Evaluations, Güli̇z Ak, Ayça Erek, Tuğba Karakayali, Şadi̇ye Çeti̇n, Şenay Şanlier
Chitosan Microparticle-Based Antibacterial Nasal Barrier Formulation And In Vivo Evaluations, Güli̇z Ak, Ayça Erek, Tuğba Karakayali, Şadi̇ye Çeti̇n, Şenay Şanlier
Turkish Journal of Chemistry
Microorganisms remain a major cause of infectious diseases, emphasizing the need for alternative and complementary antimicrobial strategies. In this context, plant-derived materials have attracted increasing attention for their antimicrobial and protective properties. Chitosan, a biocompatible and cationic biopolymer, has emerged as an effective carrier system for encapsulating such plant-derived components. In this study, chitosan microparticles were prepared through ionic gelation followed by spray drying and loaded with thyme oil and olive leaf extract. The resulting microparticles exhibited an average size of approximately 1.8 μm and a total phenolic content of 23 mg GAE/g. These microparticles were incorporated into a glycerin–starch …
Quantum Engineered Mxene–Graphene–Plasmonic Nanocomposites For Next-Generation Transparent And Flexible Space Photovoltaics, Arash Vaghef-Koodehi
Quantum Engineered Mxene–Graphene–Plasmonic Nanocomposites For Next-Generation Transparent And Flexible Space Photovoltaics, Arash Vaghef-Koodehi
Turkish Journal of Chemistry
This study presents a quantum‑engineered, tricomponent heterostructure comprising Ti3C2T MXene quantum dots (2–5 nm), single‑layer graphene, and plasmonic gold nanoparticles (15 ± 3 nm) uniformly embedded within electrospun polyacrylonitrile nanofibers. This integrated architecture demonstrates a remarkable combination of optical transparency (89.3 ± 1.1%) and power conversion efficiency (19.7 ± 0.4%) under AM0 solar illumination, representing 340% enhancement over state‑of‑the‑art transparent photovoltaic devices. A multiscale computational framework, bridging density functional theory and device‑level drift-diffusion modeling, identifies optimal interlayer spacing (3.4 ± 0.1 Å) as the key to achieving 89.3% charge‑transfer efficiency. Concurrently, localized surface plasmon resonances at 532 nm generate electromagnetic …
Efficient Heterogeneous Photo-Fenton Degradation Of Azo Dyes Using The Nanocomposite Mgfe2o4/Mos2, Zahra Zeinali, Leila Ershadi Afshar, Naz Chaibakhsh, Farnaz Isapour
Efficient Heterogeneous Photo-Fenton Degradation Of Azo Dyes Using The Nanocomposite Mgfe2o4/Mos2, Zahra Zeinali, Leila Ershadi Afshar, Naz Chaibakhsh, Farnaz Isapour
Turkish Journal of Chemistry
In the present work, a facile hydrothermal route was employed to synthesize the nanocomposite MgFe2O4/MoS2, which acted as a heterogeneous photo-Fenton catalyst for the degradation of a synthetic diazo dye, Acid Blue 113 (AB113). The nanocatalyst produced underwent analysis using multiple characterization techniques. The parameters influencing the oxidative reaction were statistically modeled and optimized using response surface methodology. Optimal degradation efficiency for AB113 (94.92%) was attained at pH 8.79 using 10 mg of MgFe2O4/MoS2 nanocatalyst, 1.6 mL of H2O2, and a reaction duration of 27 min. The synergistic effect resulting from the formation of electron-hole pairs renders the combined photocatalysis …
Electrochemical Biosensing Of Alpha-Fetoprotein Based On Carboxylated Multi-Walled Nanotube-Polyazur A (In Des)-Gold Nanoparticles, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç
Electrochemical Biosensing Of Alpha-Fetoprotein Based On Carboxylated Multi-Walled Nanotube-Polyazur A (In Des)-Gold Nanoparticles, Merve Yilmaz Çilçar, Meli̇ke Bi̇lgi̇ Kamaç
Turkish Journal of Chemistry
AFP, a cancer biomarker, is monitored during fetal development and in the serum of pregnant women. Sensitive and rapid monitoring of AFP is crucial for effective management. In this study, screen-printed carbon electrodes (SPCEs) modified with multi-walled carbon nanotubes (MWCNT-COOH), polyAzur A (PAA), which was prepared in a deep eutectic solution (DES), and gold nanoparticles (AuNP) were fabricated. AFP biosensors were developed for practical, sensitive, low-cost, and rapid detection of AFP. Optimizations of nanostructures (MWCNT-COOH, AuNP) and polymers (PAADES) were performed. The MWCNT-COOH, PAADES, and AuNP-modified SPCEs were characterized by FE-SEM-EDX, FTIR, and XRD techniques. The amounts of 6-MOH, APTES, …
[H]-Mediated Enhancement Of The Fenton Reaction Over A Pd/Uio-66(Zr)-F4 Catalyst, Juanhong Li, Suqin Wang, Xin Liu, Feng Liu
[H]-Mediated Enhancement Of The Fenton Reaction Over A Pd/Uio-66(Zr)-F4 Catalyst, Juanhong Li, Suqin Wang, Xin Liu, Feng Liu
Turkish Journal of Chemistry
A [H]-accelerated catalytic Fenton system was developed using Pd/UiO-66(Zr)-F4 as the catalyst. This system enabled the regeneration of Fe²⁺ and facilitated the continuous generation of both ·OH and 1O2 through [H]-mediated electron transfer at ambient temperature and pressure. Under the conditions of 0.2 g L−1 catalyst (Pd loading 0.516 wt%), 25 μM Fe2+, 60 mL min−1 H2 flow (as the [H] source), 20 mM H2O2, and pH 3, approximately 89% of carbamazepine (initial concentration 20 mg L−1) was degraded within 3 h using trace iron. However, the catalytic activity of Pd/UiO-66(Zr)-F4 gradually declined from 89% to 53% over six reaction …
Alcohol-Based Microextraction Of Rhodamine 6g From Soft Drink, Food, And Cosmetic Samples, Mustafa Soylak, Esra Yamaner, Özgür Özalp
Alcohol-Based Microextraction Of Rhodamine 6g From Soft Drink, Food, And Cosmetic Samples, Mustafa Soylak, Esra Yamaner, Özgür Özalp
Turkish Journal of Chemistry
By using alcohol-based solvent extraction without tetrahydrofuran, a liquid–liquid microextraction technique was developed for the separation–enrichment of trace levels of Rhodamine 6G from complex matrices, including soft drinks, food, cosmetics, hygiene products, and natural waters. Numerous experimental parameters were tuned, including pH, alcohol volume, ultrasonication time, and sample and eluent volume. The enrichment factor (EF), limit of detection (LOD), and limit of quantification (LOQ) were used to assess the analytical performance of the suggested approach. The LOD and LOQ were 6.92 ng mL−1 and 23 ng mL−1, respectively, and the EF was 14. Through the use of the standard addition …
Physically Mixed Graphene Aerogel:Carbon Black (Ga:Cb)-Supported Pt Or Hydrothermally Synthesized Ga-Pt/Cb Hybrid Electrocatalysts For Pem Fuel Cells, Emi̇ne Teke Öner, Meli̇s Irmak Aydin, Merve Ni̇da Dursunoğlu, Ayşe Bayrakçeken
Physically Mixed Graphene Aerogel:Carbon Black (Ga:Cb)-Supported Pt Or Hydrothermally Synthesized Ga-Pt/Cb Hybrid Electrocatalysts For Pem Fuel Cells, Emi̇ne Teke Öner, Meli̇s Irmak Aydin, Merve Ni̇da Dursunoğlu, Ayşe Bayrakçeken
Turkish Journal of Chemistry
Graphene aerogels (GAs), having the superior properties of graphene and aerogel structures, are promising support materials for Pt nanoparticles to be used as electrocatalysts for PEM fuel cells. In this study, two routes were followed to synthesize GA-based electrocatalysts. In the first route, after GA synthesis it was physically mixed with carbon black (CB) by changing the mass ratios from 0% to 100% with 25% increments and then decorated with Pt nanoparticles via microwave irradiation, resulting in Pt/GA:CB electrocatalysts. In the second route, firstly, Pt/CB electrocatalyst was synthesized and then GA was hydrothermally added to the Pt/CB by changing the …
A Nonenzymatic Electrochemical Glucose Sensor Depending On A Ninps/Co3o4/Functionalized Graphene Oxide-Modified Working Electrode, Sümeyra Pekmez, Muhammet Güler
A Nonenzymatic Electrochemical Glucose Sensor Depending On A Ninps/Co3o4/Functionalized Graphene Oxide-Modified Working Electrode, Sümeyra Pekmez, Muhammet Güler
Turkish Journal of Chemistry
In the present research, the aim was to develop a novel electrochemical enzyme-free glucose sensor dependent upon a nickel nanoparticles (NiNPs)/cobalt (II, III) oxide (Co3O4)/carboxylated graphene oxide (GO-COOH)-modified glassy carbon (GC) electrode. The electrocatalytic performance of the electrode was tested using various electrochemical methods such as amperometry and cyclic voltammetry (CV). The NiNPs@Co3O4/GO-COOH/GC electrode showed noticeably superior electrocatalytic behavior for glucose oxidation in 0.1 M NaOH media, ascribed to the good synergistic impact between NiNPs, Co3O4, and GO-COOH. The amperometric response of the NiNPs@Co3O4/GO-COOH/GC electrode to glucose exhibited two linear determination ranges at +0.55 V potential. The first one was …
Production, Purification, And Crystallization Of The Recombinant Her2 Tyrosine Kinase Domain (Her2-Tkd), Edanur Topalan, Hali̇li̇brahi̇m Çi̇ftçi̇, Hasan Demi̇rci̇
Production, Purification, And Crystallization Of The Recombinant Her2 Tyrosine Kinase Domain (Her2-Tkd), Edanur Topalan, Hali̇li̇brahi̇m Çi̇ftçi̇, Hasan Demi̇rci̇
Turkish Journal of Chemistry
The human epidermal growth factor receptor 2 tyrosine kinase domain (HER2-TKD) is an important therapeutic target in oncology. In this study, we developed a practical and cost-effective approach for producing soluble recombinant HER2-TKD in Escherichia coli as a basis for structure-based drug discovery. The gene encoding HER2-TKD was cloned into a pET28a(+) expression vector and expressed in E. coli. Since the protein was initially obtained as inclusion bodies, solubilization with 1.5% sarcosyl was applied to recover it in soluble form. The purified protein was obtained through size-exclusion chromatography, followed by tag removal using reverse affinity purification. Crystallization trials were performed …
Synthesis Of Two Hofmann-Type-Like Clathrates, Characterizations, And Investigation Of Their Structures, Spectroscopic And Theoretical Properties, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Synthesis Of Two Hofmann-Type-Like Clathrates, Characterizations, And Investigation Of Their Structures, Spectroscopic And Theoretical Properties, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Turkish Journal of Chemistry
This study concerns two Hofmann-type-like clathrates using 4-aminopyridine (4AP) as ligands and the transition metal atoms copper (Cu) and zinc (Zn). These clathrates have the structural features of heteronuclear tetracyanonickelate(II) and contain H2O and 4AP molecules as guest molecules, respectively. These two clathrates were characterized by infrared spectroscopy (IR), elemental analysis, and single crystal X-ray diffraction (SC-XRD) techniques. Based on elemental and spectral data, the structural formulae describing these clathrates were found to be [Cu(II)(4AP)4Ni(μ-CN)2(CN)2]·H2O (1) and [Zn(II)(4AP)4Ni(μ-CN)2(CN)2]·(4AP) (2). In addition, the values of some optical, electronic, and thermochemical properties of the two obtained clathrates calculated with the Gaussian 03 …
Vanadium’S Journey From Essential Trace Metal To Emerging Environmental Pollutant In The Anthropocene Era, Tanu Arora, Nivedita Agnihotri, Mohammad Azam
Vanadium’S Journey From Essential Trace Metal To Emerging Environmental Pollutant In The Anthropocene Era, Tanu Arora, Nivedita Agnihotri, Mohammad Azam
Turkish Journal of Chemistry
Vanadium, previously considered a minor trace element, is gaining global environmental attention due to its expanding applications in metallurgy, energy storage, catalysis, and agriculture. With this rise in its industrial and technological uses, however, anthropogenic emissions of vanadium into the atmosphere, soils, and water bodies have also escalated. Unlike many heavy metals, vanadium exhibits complex redox behavior, primarily existing as V(IV) and V(V) species, which significantly impacts its environmental mobility, bioavailability, and toxicity. Vanadium exhibits complex behavior that necessitates an integrated research approach to better understand its various roles in scientific fields. This review summarizes the current knowledge on vanadium’s …
Computational And Experimental Analysis Of Oleanolic Acid As An Allosteric Activator Of Sirt1, Emrah Sariyer, Eda Dokumacioğlu, Hati̇ce İskender
Computational And Experimental Analysis Of Oleanolic Acid As An Allosteric Activator Of Sirt1, Emrah Sariyer, Eda Dokumacioğlu, Hati̇ce İskender
Turkish Journal of Chemistry
Sirtuin 1 (SIRT1) is a member of the sirtuin protein family and the biological effects of SIRT1 encompass various areas such as the ageing process, metabolism regulation, and cellular stress response. SIRT1 activators are compounds that enhance the activity of SIRT1 enzyme. These activators can be natural or synthetic compounds and have the potential to provide health benefits by augmenting the biological effects of SIRT1. Oleanolic acid (OA) is a triterpenoid compound that has antiinflammatory, antioxidant, and glucose and lipid metabolism-regulating properties naturally found in many plants. The aim of the present study was to investigate the effect of OA …
Synthesis Of Werner- And Werner-Like-Type Clathrates, Their Characterization, And Theoretical Calculation Of Their Properties, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Synthesis Of Werner- And Werner-Like-Type Clathrates, Their Characterization, And Theoretical Calculation Of Their Properties, Zari̇fe Si̇bel Şahi̇n, Zeki̇ Kartal
Turkish Journal of Chemistry
In this paper, the synthesis and structural characterization of three new coordination compounds in crystal structure consisting of a nickel atom, varying numbers of 3-aminopyridine molecules, and two isothiocyanate ion ligands are presented. The crystal structures of these compounds were determined by single crystal X-ray diffraction. Consequently, the explicit formulas and shorthand notations of the compounds are [Ni(NCS)2(C5H6N2)2(H2O)]·(H2O) (1), [Ni(NCS)2(C5H6N2)3]·(C2H6) (2), and [Ni(NCS)2(C5H6N2)4]·2(C5H6N2) (3). The consistency of the crystal structure data was confirmed by elemental analysis and infrared spectroscopy. These coordination compounds are Werner-like-type clathrates containing water, ethane, and 3-aminopyridine molecules as guest molecules in their structures, respectively. According to …
Influence Of Precursor Synthesis Temperature And Hydrothermal Alkaline Medium On Agglomeration And Crystal Phase Of Barium Titanate Nanoparticles, Murat Özen
Turkish Journal of Chemistry
Phase‑pure, cube‑like barium titanate (BaTiO3) nanoparticles were synthesized via hydrothermal treatment of a single‑source barium-titanium peroxo-hydroxide precursor. Precursor solutions prepared at room temperature, 0 °C, and –10 °C with various storage times exhibited Ba/Ti molar ratios ranging from 0.66 to 1.05 as determined by X-ray fluorescence. Cooling the precursor solution to –10 °C effectively suppressed the polymerization of Ti-O-Ti, yielding near‑ideal stoichiometry and finer precursor particles. Subsequent hydrothermal processing in NH4OH, KOH, and NaOH (0.5–10 M, 100–200 °C) revealed the strong dependence of agglomeration and morphology on the alkaline medium. While NH4OH and KOH resulted in severe agglomeration and the …
Sensitive Stripping Voltammetric Determination Of An Anthracene–Isatin Schiff Base In Biological Samples, Gökçe Öztürk, İrem Gökgöz, Emi̇ne Arslan, Eli̇f Şi̇şman, İnci̇ Seli̇n Doğan, Di̇lek Kul, Fatma Ağin
Sensitive Stripping Voltammetric Determination Of An Anthracene–Isatin Schiff Base In Biological Samples, Gökçe Öztürk, İrem Gökgöz, Emi̇ne Arslan, Eli̇f Şi̇şman, İnci̇ Seli̇n Doğan, Di̇lek Kul, Fatma Ağin
Turkish Journal of Chemistry
In the present study, the electrochemical behavior and quantitative determination of the Schiff base 3-[(anthracen-2-yl)imino]-5-nitro-1,3-dihydro-2H-indol-2-one (ANT) were investigated for the first time using voltammetric techniques at a glassy carbon electrode. The effects of solvent composition, pH, and scan rate on the redox behavior of ANT were systematically evaluated. The compound exhibited an irreversible oxidation process governed by adsorption-controlled kinetics. Quantitative analysis was conducted using differential pulse stripping voltammetry (AdS-DPV) and square-wave stripping voltammetry (AdS-SWV) under optimized conditions. Both methods exhibited linear responses over the concentration range of 0.2–8.0 μM, with limits of detection of 0.0366 μM and 0.0433 μM for …
Investigation Of The Enzyme-Inhibitory, Antibacterial, And Anticancer Properties Of Metal Phthalocyanines, Meryem Topal, Fevzi̇ Topal, Firat Yilmaz, Esra Bulut Atalay, Ümi̇t Muhammet Koçyi̇ği̇t, Emre Güzel
Investigation Of The Enzyme-Inhibitory, Antibacterial, And Anticancer Properties Of Metal Phthalocyanines, Meryem Topal, Fevzi̇ Topal, Firat Yilmaz, Esra Bulut Atalay, Ümi̇t Muhammet Koçyi̇ği̇t, Emre Güzel
Turkish Journal of Chemistry
In this study, the enzyme inhibitory, antibacterial, and anticancer activities of a phthalonitrile derivative and its metal phthalocyanines (Pcs; indium, zinc, copper, cobalt, and manganese; 1–6) were investigated. The cobalt and manganese Pcs were synthesized for the first time in this study. The inhibitory activities of the symmetric Pcs, which were expected to interact with acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) via their 4-(isopropylbenzyl)oxy substituents through host–guest interactions, were investigated. More selective inhibition of AChE than BChE was observed for these compounds. For AChE, CoPc was identified as the most potent inhibitor (IC50 = 14.81 nM), whereas for BChE, InPc was …
Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi
Templating Effect Of Neutral Dithiane Ligands On The Self-Assembly Of Cationic Au(I)-Phosphine Units, Farzane Osanlou, Abdollah Neshat, Mohammad Reza Yousefshahi, Vaclav Eigner, Michal Dusek, Shahram Seidi
Turkish Journal of Chemistry
The interactions between the dinuclear Au(I) precursor (dppm)Au2Cl2 and neutral sulfur-containing dithianes (specifically 1,3- and 1,4-dithiane) were examined in the presence of NH₄PF₆. Although these sulfur-based ligands were initially employed to facilitate the formation of mixed phosphine/sulfur Au(I) complexes, single-crystal X-ray diffraction analysis revealed the unexpected generation of multinuclear Au(I) assemblies exclusively coordinated by phosphine ligands. When 1,3-dithiane was present, a trinuclear Au(I) complex was isolated, characterized by a central four-coordinate Au(I) center exhibiting a distorted see-saw geometry, flanked by two terminal Au(I) centers with T-shaped coordination environments. Importantly, the dithiane ligand did not coordinate directly to the gold centers …
Nucleophilic Cyclization Of N-Propargylated Pyrazole-5-Carboxylates: Synthesis Of Pyrazolo[1,5-A]Pyrazin-4(5h)-One Derivatives, Meli̇k Firat Mengeş, Meltem Tan Uygun
Nucleophilic Cyclization Of N-Propargylated Pyrazole-5-Carboxylates: Synthesis Of Pyrazolo[1,5-A]Pyrazin-4(5h)-One Derivatives, Meli̇k Firat Mengeş, Meltem Tan Uygun
Turkish Journal of Chemistry
Cyclization reactions are among the most important and widely used methods for synthesizing biologically active fused heterocyclic compounds. In the present study, pyrazolopyrazinone derivatives (10a–i) were synthesized from N-propargylated pyrazoles via nucleophilic cyclization with hydrazine hydrate under a nitrogen atmosphere. Nuclear magnetic resonance (NMR) spectral analyses confirmed that ring closure proceeded in a manner consistent with the formation of a six-membered pyrazinone moiety. In addition, the pyrazolotriazepinone derivative 15c was synthesized using an alternative approach. In this method, substitution with chloroacetone was first carried out, followed by ring closure with hydrazine hydrate, affording a seven-membered triazepinone system. Comparison of the …
Influence Of Plasticizer Type On The Structure And Drug Release Characteristics Of Lm-Pectin Hydrogels, Banu Kocaağa, Fatma Seni̇ha Güner
Influence Of Plasticizer Type On The Structure And Drug Release Characteristics Of Lm-Pectin Hydrogels, Banu Kocaağa, Fatma Seni̇ha Güner
Turkish Journal of Chemistry
This study investigated the effects of different plasticizers—castor oil (CO), polyvinylpyrrolidone (PVP), and polyethylene glycol (PEG) with varying molecular weights (MWs)—on the structure and drug-release performance of low-methoxyl pectin (LM-pectin) hydrogels. Theophylline was used as a model drug to evaluate release behavior under physiologically relevant conditions. The incorporation of plasticizers modulated polymer–polymer interactions, swelling behavior, and thermal properties, thereby affecting drug-release kinetics. CO, a hydrophobic triglyceride, created microdomain-induced diffusion pathways; PVP, containing water-affinitive lactam units, facilitated moisture-driven plasticization; and PEG (MW 400/1000/1500), with hydroxyl-terminated chains, established hydrogen bonds with pectin. Structural analyses (FTIR and DSC) revealed that CO disrupted pectin …
Antioxidant Potential Of Sulfenimides In Waste Walnut Oil Biodiesel: Kinetic Stability, Phosphomolybdenum Activity, And Reducing Power Capacity, Nalan Türköz Karakullukçu, Hasan Yakan, Volkan Murat Yilmaz, Hali̇t Muğlu, Semi̇ha Yeni̇gün, Hali̇l Kütük
Antioxidant Potential Of Sulfenimides In Waste Walnut Oil Biodiesel: Kinetic Stability, Phosphomolybdenum Activity, And Reducing Power Capacity, Nalan Türköz Karakullukçu, Hasan Yakan, Volkan Murat Yilmaz, Hali̇t Muğlu, Semi̇ha Yeni̇gün, Hali̇l Kütük
Turkish Journal of Chemistry
This study investigated the influence of synthetic sulfenimides on biodiesel–diesel fuel blends. Three previously synthesized sulfenimide derivatives were structurally characterized using spectroscopic techniques. We evaluated their antioxidant properties through phosphomolybdenum activity and reducing power capacity assays. The tested fuel samples were designated as D100, B10D90, B10D90_AA (ascorbic acid), B10D90_3, B10D90_2, and B10D90_1. The effect of adding 2000 ppm of the additive was measured using an Oxifast instrument following the ASTM D7545 standard, and the results were compared to those of the chemical antioxidant ascorbic acid. Inhibition time values were derived from the oxidation stability results. The starting temperatures for crystallization …
Investigating The Structure And Bioactivity Of Lanthanum Coordination Compounds, Shantanu Kadam, Bhushan Dhale, Bapu Yamgar, Swaminath Bhattar
Investigating The Structure And Bioactivity Of Lanthanum Coordination Compounds, Shantanu Kadam, Bhushan Dhale, Bapu Yamgar, Swaminath Bhattar
Turkish Journal of Chemistry
Lanthanum metal complexes were synthesized using a classical condensation method by reacting lanthanum nitrate salts with a bidentate ligand in a 1:2:1 molar ratio (M:L:L). The formation and structure of the resulting complexes were confirmed through a combination of analytical techniques, including Fourier transformation infrared spectroscopy, thermal gravimetric analysis, X-ray diffraction, elemental microanalysis, and scanning electron microscopy. The lanthanum complexes synthesized exhibited strong in vitro antimicrobial activity. Antibacterial screening showed inhibition zones of 18–26 mm against Staphylococcus aureus and Escherichia coli, surpassing those of the reference drug ciprofloxacin (16–20 mm). Antifungal studies demonstrated inhibition zones of 15–23 mm against Candida …
Development And Optimization Of A Novel Spectroscopic Method To Monitor Crystallization Behavior Of Bcs-Ii Drug, Uditi Handa, Anuj Malik, Kumar Guarve
Development And Optimization Of A Novel Spectroscopic Method To Monitor Crystallization Behavior Of Bcs-Ii Drug, Uditi Handa, Anuj Malik, Kumar Guarve
Turkish Journal of Chemistry
This study investigated the crystallization behavior of dextromethorphan hydrobromide, a class II drug, to improve understanding of its supersaturation potential and formulation design. Conventional methods often lack the sensitivity or scalability needed for accurate detection of early nucleation events. To overcome these limitations, a novel process tracks real-time absorbance below turbidity levels to detect early molecular aggregation and phase separation. Crystallization kinetics of the drug was assessed at concentrations of 0.1, 0.2, and 0.3 mg/mL using three analytical techniques, namely, isothermal crystallization (baseline), ultraviolet (UV) absorbance (turbidity monitoring, UV-TM), and an optimized UV absorbance graphical method (UV-GM) (novel process). Induction …