149 results on '"Kasim Ocakoglu"'
Search Results
2. Selective Photokilling of Human Pancreatic Cancer Cells Using Cetuximab-Targeted Mesoporous Silica Nanoparticles for Delivery of Zinc Phthalocyanine
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Özge Er, Suleyman Gokhan Colak, Kasim Ocakoglu, Mine Ince, Roger Bresolí-Obach, Margarita Mora, Maria Lluïsa Sagristá, Fatma Yurt, and Santi Nonell
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Zn(II) phthalocyanine ,mesoporous silica nanoparticles ,Cetuximab ,singlet oxygen ,photodynamic therapy ,Organic chemistry ,QD241-441 - Abstract
Background: Photodynamic therapy (PDT) is a non-invasive and innovative cancer therapy based on the photodynamic effect. In this study, we sought to determine the singlet oxygen production, intracellular uptake, and in vitro photodynamic therapy potential of Cetixumab-targeted, zinc(II) 2,3,9,10,16,17,23,24-octa(tert-butylphenoxy))phthalocyaninato(2-)-N29,N30,N31,N32 (ZnPcOBP)-loaded mesoporous silica nanoparticles against pancreatic cancer cells. Results: The quantum yield (ΦΔ) value of ZnPcOBP was found to be 0.60 in toluene. In vitro cellular studies were performed to determine the dark- and phototoxicity of samples with various concentrations of ZnPcOBP by using pancreatic cells (AsPC-1, PANC-1 and MIA PaCa-2) and 20, 30, and 40 J/cm2 light fluences. No dark toxicity was observed for any sample in any cell line. ZnPcOBP alone showed a modest photodynamic activity. However, when incorporated in silica nanoparticles, it showed a relatively high phototoxic effect, which was further enhanced by Cetuximab, a monoclonal antibody that targets the Epidermal Growth Factor Receptor (EGFR). The cell-line dependent photokilling observed correlates well with EGFR expression levels in these cells. Conclusions: Imidazole-capped Cetuximab-targeted mesoporous silica nanoparticles are excellent vehicles for the selective delivery of ZnPcOBP to pancreatic cancer cells expressing the EGFR receptor. The novel nanosystem appears to be a suitable agent for photodynamic therapy of pancreatic tumors.
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- 2018
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3. Synthesis of Rhombic Dodecahedral Cuprous Oxide Nanoparticles and Investigation of Biological Activity
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Rıdvan Küçükosman, Zelal Isik, Sadin Özdemir, Serpil Gonca, Kasim Ocakoglu, and Nadir Dizge
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Biomedical Engineering ,Bioengineering - Published
- 2022
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4. Diazonium-Based Covalent Molecular Wiring of Single-Layer Graphene Leads to Enhanced Unidirectional Photocurrent Generation through the p-doping Effect
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Margot Jacquet, Silvio Osella, Ersan Harputlu, Barbara Pałys, Monika Kaczmarek, Ewa K. Nawrocka, Adam A. Rajkiewicz, Marcin Kalek, Paweł P. Michałowski, Bartosz Trzaskowski, C. Gokhan Unlu, Wojciech Lisowski, Marcin Pisarek, Krzysztof Kazimierczuk, Kasim Ocakoglu, Agnieszka Więckowska, and Joanna Kargul
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Grafting (chemical) ,Electrografting ,General Chemical Engineering ,Conductive materials ,Cost effectiveness ,Covalent attachment ,Metal complexes ,Wire ,Materials Chemistry ,Nano-engineering ,Redox reactions ,Technological solution ,P-doping ,Tin oxides ,Proteins ,General Chemistry ,Electron transitions ,Diazonium salts ,Metals ,Doping effects ,Density functional theory ,Heterojunctions ,Graphene ,Single layer ,Cost effective ,Photocurrent generations - Abstract
Development of robust and cost-effective smart materials requires rational chemical nanoengineering to provide viable technological solutions for a wide range of applications. Recently, a powerful approach based on the electrografting of diazonium salts has attracted a great deal of attention due to its numerous technological advantages. Several studies on graphene-based materials reveal that the covalent attachment of aryl groups via the above approach could lead to additional beneficial properties of this versatile material. Here, we developed the covalently linked metalorganic wires on two transparent, cheap, and conductive materials: fluorine-doped tin oxide (FTO) and FTO/single-layer graphene (FTO/SLG). The wires are terminated with nitrilotriacetic acid metal complexes, which are universal molecular anchors to immobilize His6-tagged proteins, such as biophotocatalysts and other types of redox-active proteins of great interest in biotechnology, optoelectronics, and artificial photosynthesis. We show for the first time that the covalent grafting of a diazonium salt precursor on two different electron-rich surfaces leads to the formation of the molecular wires that promote p-doping of SLG concomitantly with a significantly enhanced unidirectional cathodic photocurrent up to 1 ?A cm-2. Density functional theory modeling reveals that the exceptionally high photocurrent values are due to two distinct mechanisms of electron transfer originating from different orbitals/bands of the diazonium-derived wires depending on the nature of the chelating metal redox center. Importantly, the novel metalorganic interfaces reported here exhibit minimized back electron transfer, which is essential for the maximization of solar conversion efficiency. © 2022 American Chemical Society. All rights reserved.
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- 2022
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5. Optimization of Sn-Based Perovskite Solar Cells with the Antisolvent Doped by Acetaldoxime
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Wenjin Zeng, Chaochao Yuan, Yuting Shi, Enzhi Li, Wei Hua, Qiaoli Niu, Kasim Ocakoglu, Ruidong Xia, and Yong Min
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Biomaterials ,Materials Chemistry ,General Chemistry ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials - Published
- 2023
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6. Experimental confirmation of antimicrobial effects of GdYVO4:Eu3+ nanoparticles
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Serpil Gonca, Sadin Özdemir, Svetlana Yefimova, Anton Tkachenko, Anatolii Onishchenko, Vladimir Klochkov, Nataliya Kavok, Pavel Maksimchuk, Nadir Dizge, and Kasim Ocakoglu
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Pharmacology ,Organic Chemistry ,Drug Discovery ,Pharmaceutical Science - Published
- 2021
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7. Preparation of ZnO nanorods or SiO2 nanoparticles grafted onto basalt ceramic membrane and the use for E. coli removal from water
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Mutlu Yalvac, Zelal Isik, Sadin Özdemir, Ersan Harputlu, Serpil Gonca, Mohammed Saleh, Nadir Dizge, Yasin Ozay, and Kasim Ocakoglu
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010302 applied physics ,Materials science ,Fabrication ,Process Chemistry and Technology ,Biofilm ,Sintering ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Membrane ,Ceramic membrane ,Chemical engineering ,Permeability (electromagnetism) ,Sio2 nanoparticles ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,Nanorod ,0210 nano-technology - Abstract
This article addresses the fabrication of a novel and eco-friendly ceramic membrane based on basalt powder via press and sintering methods with a pore size of 1.5–2 μm. The basalt ceramic membrane (BCM) was grafted by SiO2 nanoparticles (50–60 nm) and ZnO nanorods (2.2 μm). The water permeability for the prepared membranes was measured 345.3, 701.4, and 801.9 L/m2 h bar for bare BCM, SiO2-BCM, and ZnO-BCM, respectively. The prepared membranes were used in Escherichia coli (E. coli) removal, and 100% E. coli removal efficiency was achieved at a transmembrane pressure of 0.5 bar for all membranes. The antimicrobial activities of the solid surfaces for BCM, SiO2-BCM, and ZnO-BCM were also studied using E. coli as a model test microorganisms. The antimicrobial activities for bare BCM, SiO2-BCM, and ZnO-BCM were 20.57%, 74.90%, and 100%, respectively. The results are of great importance in terms of the reusability of membranes and the prevention of biofilm formation in wastewater treatment processes.
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- 2021
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8. Antimicrobial activity enhancement of PVA/chitosan films with the additive of CZTS quantum dots
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Seda Ceylan, Rıdvan Küçükosman, Fatma Yurt, Derya Özel, İsmail Öztürk, Didem Demir, and Kasim Ocakoglu
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Chitosan ,Membranes ,Polymers and Plastics ,Miscibility ,Solar-Cells ,Hydrogels ,General Chemistry ,Condensed Matter Physics ,CZTS ,Nanocrystals ,Hydrothermal Synthesis ,PVA ,Cu2ZnSnS4 quantum dots ,Cu2znsns4 ,Materials Chemistry ,Nanoparticles - Abstract
The wound environment is a breeding ground for pathogens, and traditional wound dressing materials lack antibacterial properties. In this work, we aimed to develop PVA/chitosan (P/C)-based wound dressing scaffolds with anti-infective properties using Cu2ZnSnS4 quantum dots (CZTS QDs) to prevent infections in the wound. CZTS quantum dots were prepared by a simple hydrothermal process and characterized using appropriate techniques such as TEM, XRD, FTIR spectrum, and UV-Vis absorption spectroscopy. CZTS QDs were subsequently loaded at different concentrations onto PVA/chitosan membranes (0, 1.6, 2.5 and 3.3% w/w, based on the total polymer quantity). The chemical structure, contact angle and mechanical properties of the membranes were analyzed, and their antimicrobial activities and cell viability were also investigated. The cytocompatibility of the membranes and cell morphology was investigated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and SEM. Based on studies on the interactions between membranes and cells, it was determined that incorporation of CZTS QDs into the membrane did not cause toxicity. To the best of our knowledge, this is the first report on loading CZTS QDs into membranes for tissue engineering applications, and the overall findings suggest that CZTS QDs-integrated membranes might have potentially appealing uses as antimicrobial films for wound healing., Tarsus University Scientific Research Projects Coordination Department; [MF.22.003], AcknowledgementsThe authors thank the Tarsus University Scientific Research Projects Coordination Department (Project no: MF.22.003) for the supports.
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- 2022
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9. Antimicrobial activity and cytotoxicity study of cerium oxide nanoparticles with two different sizes
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Svetlana Yefimova, Vladimir Klochkov, Nataliya Kavok, Anton Tkachenko, Anatolii Onishchenko, Tatyana Chumachenko, Nadir Dizge, Sadin Özdemir, Serpil Gonca, and Kasim Ocakoglu
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Biomaterials ,Biomedical Engineering - Abstract
The control over bacterial diseases requires the development of novel antibacterial agents. The use of antibacterial nanomedicines is one of the strategies to tackle antibiotic resistance. The study was designed to assess the antimicrobial activity of cerium oxide (CeO
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- 2022
10. Improving the Photocatalytic Hydrogen Generation Using Nonaggregated Zinc Phthalocyanines
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Mustafa Güllü, Eminegül Genc Acar, Ersan Harputlu, Gülbin Kurtay, Emre Aslan, Kasim Ocakoglu, Mine Ince, Imren Hatay Patir, A. Celil Yüzer, and Gizem Yanalak
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Materials science ,chemistry ,Materials Chemistry ,Electrochemistry ,Photocatalysis ,Energy Engineering and Power Technology ,Chemical Engineering (miscellaneous) ,chemistry.chemical_element ,Zinc ,Electrical and Electronic Engineering ,Photochemistry ,Hydrogen production - Published
- 2021
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11. Experimental studies on combustion and atomization characteristics of aliphatic and aromatic hydrocarbons droplets
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Rıdvan Küçükosman, Ahmet Alper Yontar, and Kasim Ocakoglu
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- 2023
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12. Detection of Kallikrein-Related Peptidase 4 with a Label-free Electrochemical Impedance Biosensor Based on a Zinc(II) Phthalocyanine Tetracarboxylic Acid-Functionalized Disposable Indium Tin Oxide Electrode
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Kasim Ocakoglu, Muhammet Aydın, Abdulcelil Yuzer, Mine Ince, Mustafa Kemal Sezgintürk, and Elif Burcu Aydın
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Indoles ,0206 medical engineering ,Biomedical Engineering ,chemistry.chemical_element ,Biosensing Techniques ,02 engineering and technology ,Zinc ,Isoindoles ,Biomaterials ,Matrix (chemical analysis) ,chemistry.chemical_compound ,Electric Impedance ,Organometallic Compounds ,Electrodes ,Detection limit ,Tin Compounds ,Electrochemical Techniques ,021001 nanoscience & nanotechnology ,020601 biomedical engineering ,Combinatorial chemistry ,Dielectric spectroscopy ,Indium tin oxide ,chemistry ,Zinc Compounds ,Electrode ,Phthalocyanine ,Kallikreins ,0210 nano-technology ,Biosensor - Abstract
A new impedimetric biosensing system based on kallikrein-related peptidase 4 (KLK 4) antigen-specific antibodies and a zinc(II) phthalocyanine tetracarboxylic acid (Zn-PcTCa) matrix material was developed for the first time in this study. First, a Zn-PcTCa-coated indium tin oxide surface was used as an interface matrix material for the immobilization of anti-KLK 4 antibodies, and they bound to the platform via amide bonds. In the presence of KLK 4 antigens, the anti-KLK 4 antibodies specifically captured these antigens and caused changes in the electrochemical properties of the system. Randles equivalent circuit was utilized to evaluate the impedimetric signal, which was measured with the help of an electrochemical impedance spectroscopy method. After the specific interaction, the electron transfer resistance (Rct) was remarkably increased and displayed a linear relationship with the level of the KLK 4 antigen in the range of 0.02-15 pg/mL, with a a detection limit of 6.8 fg/mL. The designed biosensor was able to detect a KLK 4 antigen with good sensitivity, excellent specificity, and high stability. In addition, because of having a low-cost and robust procedure for fabrication, it could be repeatedly used in several areas including clinical diagnosis.
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- 2021
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13. Imidazole substituted Zinc(<scp>ii</scp>) phthalocyanines for co-catalyst-free photoelectrochemical and photocatalytic hydrogen evolution: influence of the anchoring group
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Eminegul Genc, Gülbin Kurtay, Ersan Harputlu, Gizem Yanalak, Kasim Ocakoglu, Mine Ince, A. Celil Yüzer, Emre Aslan, and Imren Hatay Patir
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chemistry.chemical_classification ,Carboxylic acid ,Energy conversion efficiency ,Metals and Alloys ,chemistry.chemical_element ,General Chemistry ,Zinc ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Turnover number ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Ceramics and Composites ,Photocatalysis ,Imidazole ,Irradiation ,Nuclear chemistry - Abstract
Novel zinc phthalocyanine derivatives, ZnPc-1 and ZnPc-2, consisting of one and four imidazole units, respectively, have been synthesized and utilized as panchromatic photosensitizers for photocatalytic and photoelectrochemical H2 evolution. The effect of the imidazole-anchoring group on the photocatalytic H2 production has been compared with ZnPc-3, which possesses a carboxylic acid unit as the anchoring group. ZnPc-1/TiO2 shows the best photoactivity with the highest H2 evolution rate of 0.4006 mmol g−1 h−1, which is much higher than that of ZnPc-2/TiO2 and ZnPc-3/TiO2 (0.3319 mmol g−1 h−1 and 0.3555 mmol g−1 h−1, respectively). After 20 h of irradiation, ZnPc-1 produces an H2 production rate of 3.4187 mmol g−1 with a turnover number (TON) of 14863 and a solar-to-hydrogen energy (STH) conversion efficiency of 1.03%, without using a co-catalyst.
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- 2021
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14. Structural, electrical and magnetic properties of Au doped Bi-2212 superconductors
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Esen Gün, Berdan Özkurt, Kasim Ocakoglu, and Mehmet Ersin Aytekin
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Superconductivity ,Materials science ,Condensed matter physics ,Doping - Published
- 2021
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15. Molecular mechanism of direct electron transfer in the robust cytochrome-functionalised graphene nanosystem
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Miriam Izzo, Bartosz Trzaskowski, Małgorzata Kiliszek, Ersan Harputlu, Margot Jacquet, Kasim Ocakoglu, Jaroslaw Sar, Silvio Osella, C. Gokhan Unlu, and Joanna Kargul
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Monolayers ,Electrochemical Properties ,Materials science ,Biophotovoltaics ,Graphene ,Performance ,General Chemical Engineering ,Oxide ,Rational design ,General Chemistry ,Photocurrent Generation ,Redox ,law.invention ,Electron transfer ,Transition metal ,Chemical physics ,law ,Photosystem-I ,Monolayer ,Molecule ,Gold ,HOMO/LUMO - Abstract
Construction of green nanodevices characterised by excellent long-term performance remains high priority in biotechnology and medicine. Tight electronic coupling of proteins to electrodes is essential for efficient direct electron transfer (DET) across the bio-organic interface. Rational modulation of this coupling depends on in-depth understanding of the intricate properties of interfacial DET. Here, we dissect the molecular mechanism of DET in a hybrid nanodevice in which a model electroactive protein, cytochrome c(553) (cyt c(553)), naturally interacting with photosystem I, was interfaced with single layer graphene (SLG) via the conductive self-assembled monolayer (SAM) formed by pyrene-nitrilotriacetic acid (pyr-NTA) molecules chelated to transition metal redox centers. We demonstrate that efficient DET occurs between graphene and cyt c(553) whose kinetics and directionality depends on the metal incorporated into the bio-organic interface: Co enhances the cathodic current from SLG to haem, whereas Ni exerts the opposite effect. QM/MM simulations yield the mechanistic model of interfacial DET based on either tunnelling or hopping of electrons between graphene, pyr-NTA-M2+ SAM and cyt c(553) depending on the metal in SAM. Considerably different electronic configurations were identified for the interfacial metal redox centers: a closed-shell system for Ni and a radical system for the Co with altered occupancy of HOMO/LUMO levels. The feasibility of fine-tuning the electronic properties of the bio-molecular SAM upon incorporation of various metal centers paves the way for the rational design of the optimal molecular interface between abiotic and biotic components of the viable green hybrid devices, e.g. solar cells, optoelectronic nanosystems and solar-to-fuel assemblies.
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- 2021
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16. Experimental confirmation of antimicrobial effects of GdYVO
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Serpil, Gonca, Sadin, Özdemir, Svetlana, Yefimova, Anton, Tkachenko, Anatolii, Onishchenko, Vladimir, Klochkov, Nataliya, Kavok, Pavel, Maksimchuk, Nadir, Dizge, and Kasim, Ocakoglu
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Staphylococcus aureus ,Anti-Infective Agents ,Biofilms ,Pseudomonas aeruginosa ,Metal Nanoparticles ,Nanoparticles ,Microbial Sensitivity Tests ,Anti-Bacterial Agents - Abstract
Nanotechnology can be applied to design antibacterial agents to combat antibiotic resistance. The aim of the present study was to assess the antimicrobial effects and cytotoxicity of GdYVO
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- 2022
17. Water-Based Synthesis of Copper Chalcogenide Structures and Their Photodynamic Immunomodulatory Activities on Mammalian Macrophages
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Furkan Ayaz, Suleyman Gokhan Colak, and Kasim Ocakoglu
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Inflammation ,Mammals ,Macrophages ,Anti-Inflammatory Agents ,Water ,Bioengineering ,General Medicine ,Applied Microbiology and Biotechnology ,Biochemistry ,Autoimmune Diseases ,Animals ,Molecular Biology ,Copper ,Biotechnology - Abstract
Generation of novel and versatile immunomodulatory agents that could suppress excessive inflammation has been crucial to fight against chronic inflammatory and autoimmune disorders. Immunomodulatory agents regulate the function of immune system cells to manage their activities. Current therapy regimens for the inflammatory and autoimmune disorders rely on immunomodulatory drug molecules but they are also associated with unwanted and severe side effects. In order to prevent the side effects associated with drug molecules, the field should generate novel immunomodulatory drug candidates and further test them. Moreover, the generation of photodynamic immunomodulatory molecules would also decrease possible side effects. Photodynamic activation enables specific and localized activation of the active ingredients upon exposure to a certain wavelength of light. In our study, we generated copper-based chalcogenide structures in gel and nanoparticle form by using a water-based method so that they are more biocompatible.After their chemical characterization, they were tested on mammalian macrophages in vitro. Our results suggest that these molecules were anti-inflammatory in dark conditions and their anti-inflammatory potentials significantly increased upon xenon light treatment. We are presenting novel photodynamic immunomodulatory agents that can be used to suppress excessive inflammation in disease conditions that have been associated with excessive inflammation.
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- 2022
18. Development of ruthenium oxide modified polyethersulfone membranes for improvement of antifouling performance including decomposition kinetic of polymer
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Basak Yigit, Yasin Ozay, Fatih Mehmet Emen, Emine Kutlu, Kasim Ocakoglu, and Nadir Dizge
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Environmental Engineering ,Polymers and Plastics ,Materials Chemistry - Abstract
In this study, RuO2-embedded PES membrane was prepared and it was used for protein separation. The antifouling properties of the fabricated composite membranes were also investigated using bovine serum albumin (BSA) as protein solution. The mean roughness increased proportionally by introducing RuO2 particles. The porosity of the composite membranes was higher than that of the pristine PES membrane. On the other hand, composite membranes has smaller average pore size after addition of RuO2 particles. The blending of RuO2 particles to the PES membrane caused to increase the hydrophilicity of the pristine membrane from 76.67° to 67.13°. The thermal studies of the PES/RuO2 membranes were performed by DTA/TG. The Activation Energy (Ea) values of the PES/RuO2 membranes were found to be 57.67-641.34 kJ/mol for Flynn-Wall-Ozawa (FWO) and 55.13–659.10 kJ/mol for Kissenger-Akahira-Sunose (KAS). The pure water flux of the composite membranes decreased from the pristine PES to PES/RuO2 1.00 wt%. The pore size was calculated as 14.5 nm and pore size decreased up to 6.5 nm when blended RuO2 particles increased up to 1.00 wt.%. BSA fluxes were 84.1 ± 2.1, 86.3 ± 2.5, and 93.9 ± 3.2 L/m2/h for pristine, PES/RuO2 0.50 wt%, and PES/RuO2 0.75 wt% membranes, respectively. PES/RuO2 1.00 wt%. membrane supplied the lowest BSA flux (73.6 ± 3.1 L/m2/h). BSA rejection efficiencies increased from 45.5 ± 1.8% to 92.6 ± 1.5% when blended RuO2 particles increased from 0 to 1.00 wt%. The results depicted that Rir values decreased while Rr values increased after the blending of RuO2.
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- 2022
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19. The effect of central metal in phthalocyanine for photocatalytic hydrogen evolution via artificial photosynthesis
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Kasim Ocakoglu, Mine Ince, Gizem Yanalak, Ersan Harputlu, A. Celil Yüzer, Eminegul Genc, Emre Aslan, and Imren Hatay Patir
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Materials science ,060102 archaeology ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Electron donor ,06 humanities and the arts ,02 engineering and technology ,Photochemistry ,Artificial photosynthesis ,Metal ,chemistry.chemical_compound ,chemistry ,Triethanolamine ,visual_art ,0202 electrical engineering, electronic engineering, information engineering ,medicine ,Phthalocyanine ,Photocatalysis ,visual_art.visual_art_medium ,Water splitting ,0601 history and archaeology ,medicine.drug ,Visible spectrum - Abstract
Phthalocyanines (Pcs) are promising sensitizers in photocatalytic hydrogen evolution reaction from water splitting owing to the unique absorption properties and familiar sensitizers for light phase of photosynthesis. In this paper, two phthalocyanines (Pcs) bearing tetra carboxylic acid at the peripheral position with Zn and Co atoms as a central metal have been prepared in order to investigate the effect of the central metal atoms on the performance of photocatalytic hydrogen evolution from water splitting for mimicking photosynthesis. The photoelectrochemical and photocatalytic hydrogen evolution experiments have been carried out by using Pcs sensitized TiO2 (TiO2, ZnPc/TiO2 and CoPc/TiO2) and Pt co-catalyst in the presence of triethanolamine (TEOA) as a sacrificial electron donor under visible light. The hydrogen production rate of ZnPc/TiO2 and CoPc/TiO2 have been determined as the 1146 and 1051 μmolg−1h−1, respectively. The hydrogen evolution rates of ZnPc/TiO2 and CoPc/TiO2 have been enhanced by in situ photodeposited Pt, which are reached by 3448 and 3328 μmolg−1h−1 for the ZnPc/TiO2/Pt and CoPc/TiO2/Pt, respectively. These results have been established that ZnPc sensitized TiO2 shows more photocatalytic activity than CoPc sensitized TiO2 in the both absence and presence of Pt. These obtained results can be attributed to the spectral response of Pc sensitizers.
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- 2020
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20. Unique photodynamic antimicrobial Schiff bases and their copper complexes exert immunomodulatory activity on mammalian macrophages
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Burcu Demirbag, Furkan Ayaz, Kasim Ocakoglu, and İlyas Gönül
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Hospitalized patients ,medicine.drug_class ,Chemistry ,fungi ,Antibiotics ,food and beverages ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,Antimicrobial ,01 natural sciences ,0104 chemical sciences ,Microbiology ,Antibiotic resistance ,Materials Chemistry ,medicine ,Macrophage ,Physical and Theoretical Chemistry - Abstract
Antibiotic resistance has been a growing problem for the public health. Especially the hospitalized patients are at high risk due to emergence of superbugs that can evade a wide range of antibiotics in use. In order to circumvent this major problem, new candidates of antimicrobial agents should be created and tested for their efficacies. Moreover, having antimicrobial agents that could get activated with light exposure (antimicrobial PDT) would create a great advantage in terms of decreasing the required effective dose as well as controlled localized activation of the candidate drugs. Schiff base derivatives have antimicrobial, antitumor, and anti-inflammatory activities. In this study, we used a unique set of Schiff base derivatives with and without copper for antimicrobial PDT applications both on gram-negative Escherichia coli and gram-positive Staphylococcus aureus. Our compounds had strong antimicrobial PDT potential especially with the addition of copper into their structures. Moreover, these Schiff base derivatives’ possible immunomodulatory activities were tested on mammalian macrophages in vitro. These compounds had photodynamic anti-inflammatory activities as well. Our results suggest that these unique Schiff bases can be utilized in antimicrobial PDT applications that can also alter the function of the immune system cells to suppress excessive inflammation.
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- 2020
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21. Investigating the Immunostimulatory and Immunomodulatory Effects of cis and trans Isomers of Ruthenium Polypyridyl Complexes on the Mammalian Macrophage‐Like Cells
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Kasim Ocakoglu, Furkan Ayaz, and Suleyman Gokhan Colak
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Innate immune system ,chemistry ,Biochemistry ,medicine ,Macrophage ,chemistry.chemical_element ,Inflammation ,Biological activity ,General Chemistry ,medicine.symptom ,Cis–trans isomerism ,Ruthenium - Published
- 2020
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22. Subphthalocyanine-sensitized TiO2 photocatalyst for photoelectrochemical and photocatalytic hydrogen evolution
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Imren Hatay Patir, Kasim Ocakoglu, Mine Ince, Eminegul Genc, A. Celil Yüzer, Gizem Yanalak, Ersan Harputlu, and Emre Aslan
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Inorganic Chemistry ,chemistry.chemical_classification ,chemistry ,Carboxylic acid ,Photocatalysis ,Water splitting ,Tio2 photocatalyst ,Hydrogen evolution ,Photochemistry ,Redox - Abstract
A series of SubPcs comprising a carboxylic acid anchoring group at the peripheral (SubPcs 1, 2) or axial position (SubPc 3) were synthesized and used as sensitizers for photocatalytic H2 production, for the first time. SubPc 3/TiO2 shows the best photocatalytic activity with a hydrogen evolution rate of 1396 μmol h−1, which is much higher than that of SubPcs 1 and 2 (771 and 658 μmol g−1, respectively). This work clearly shows that considering their optical and redox properties, SubPcs are promising candidates for light-driven water splitting systems.
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- 2020
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23. Plasmonic enhancement of photocurrent generation in a photosystem I-based hybrid electrode
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Marcin Szalkowski, Sebastian Mackowski, Małgorzata Kiliszek, Joanna Kargul, Ersan Harputlu, Kasim Ocakoglu, Dorota Kowalska, and C. Gokhan Unlu
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Materials science ,Photocurrents ,Oriented assembly ,Physics::Optics ,Photosystem I ,Fluorescence ,law.invention ,law ,Monolayer ,Materials Chemistry ,Absorption (electromagnetic radiation) ,Plasmon ,Fluorescence microscopy ,Photocurrent ,Emission intensity ,Graphene ,business.industry ,Absorption and emissions ,Silver island films ,Hybrid electrodes ,Fluorescence intensities ,General Chemistry ,Electrochemical electrodes ,Strong enhancement ,Electrode ,Plasmonics ,Optoelectronics ,business ,Layer (electronics) ,Photocurrent generations - Abstract
We experimentally demonstrate that oriented assembly of red algal photosystem I (PSI) reaction centers on a plasmonically active Silver Island Film (SIF) leads to strong enhancement of both the fluorescence intensity and photocurrent generated upon illumination. PSI complexes were specifically attached to a monolayer of graphene deposited on the SIF layer. The results of comprehensive fluorescence microscopy point to the critical role of the SIF layer in enhancing the optical response of PSI, as we observe increased emission intensity. Hence, importantly, the strong increase of photocurrent generation demonstrated for the biohybrid electrodes can be directly associated with the plasmonic enhancement of the optical and electrochemical functionalities of PSI. The results also indicate that the graphene layer is not diminishing the influence of the plasmonic excitations in SIF on the absorption and emission of PSI. © The Royal Society of Chemistry 2020.
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- 2020
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24. Preparation of S-Scheme g-C3N4/ZnO Heterojunction Composite for Highly Efficient Photocatalytic Destruction of Refractory Organic Pollutant
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Buse Sert, Zeynep Bilici, Kasim Ocakoglu, Nadir Dizge, Tannaz Sadeghi Rad, and Alireza Khataee
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S-scheme photocatalyst ,crystal violet ,advanced oxidation processes ,g-C3N4/ZnO ,Physical and Theoretical Chemistry ,Catalysis ,General Environmental Science - Abstract
In this study, graphitic carbon nitride (g-C3N4)-based ZnO heterostructure was synthesized using a facile calcination method with urea and zinc nitrate hexahydrate as the initiators. According to the scanning electron microscopic (SEM) images, spherical ZnO particles can be seen along the g-C3N4 nanosheets. Additionally, the X-ray diffraction (XRD) analysis reveals the successful synthesis of the g-C3N4/ZnO. The photocatalytic activity of the synthesized catalyst was tested for the decolorization of crystal violet (CV) as an organic refractory contaminant. The impacts of ZnO molar ratio, catalyst amount, CV concentration, and H2O2 concentration on CV degradation efficiency were investigated. The obtained outcomes conveyed that the ZnO molar ratio in the g-C3N4 played a prominent role in the degradation efficiency, in which the degradation efficiency reached 95.9% in the presence of 0.05 mmol of ZnO and 0.10 g/L of the catalyst in 10 mg/L of CV through 120 min under UV irradiation. Bare g-C3N4 was also tested for dye decolorization, and a 76.4% dye removal efficiency was obtained. The g-C3N4/ZnO was also tested for adsorption, and a 32.3% adsorption efficiency was obtained. Photocatalysis, in comparison to adsorption, had a dominant role in the decolorization of CV. Lastly, the results depicted no significant decrement in the CV degradation efficiency in the presence of the g-C3N4/ZnO photocatalyst after five consecutive runs.
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- 2023
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25. Antimicrobial Effects of Nanostructured Rare-Earth-Based Orthovanadates
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Serpil Gonca, Svetlana Yefimova, Nadir Dizge, Anton Tkachenko, Sadin Özdemir, Volodymyr Prokopiuk, Vladimir Klochkov, Nataliya Kavok, Anatolii Onishchenko, Pavel Maksimchuk, Dmytro Butov, and Kasim Ocakoglu
- Subjects
Staphylococcus aureus ,Anti-Infective Agents ,General Medicine ,Microbial Sensitivity Tests ,Vanadates ,Applied Microbiology and Biotechnology ,Microbiology ,Anti-Bacterial Agents ,Nanostructures - Abstract
The search for novel antimicrobial agents is of huge importance. Nanomaterials can come to the rescue in this case. The aim of this study was to assess the cytotoxicity and antimicrobial effects of rare-earth-based orthovanadate nanoparticles. The cytotoxicity against host cells and antimicrobial activity of LaVO
- Published
- 2021
26. Development of a Novel Nanoarchitecture of the Robust Photosystem I from a Volcanic Microalga Cyanidioschyzon merolae on Single Layer Graphene for Improved Photocurrent Generation
- Author
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Margot Jacquet, Tomasz Goral, Ersan Harputlu, Shin-ya Miyagishima, Joanna Kargul, Kasim Ocakoglu, Piotr Wróbel, Miriam Izzo, C. Gokhan Unlu, Radosław Mazur, and Takayuki Fujiwara
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System ,Electron-Transfer ,02 engineering and technology ,01 natural sciences ,law.invention ,law ,Biology (General) ,Spectroscopy ,single layer graphene ,biohybrid nanodevices ,biology ,General Medicine ,021001 nanoscience & nanotechnology ,Computer Science Applications ,Chemistry ,Cyanidioschyzon merolae ,Mechanism ,0210 nano-technology ,Cobalt ,Materials science ,photosystem I ,QH301-705.5 ,chemistry.chemical_element ,Nanotechnology ,010402 general chemistry ,Photosystem I ,Redox ,Catalysis ,Inorganic Chemistry ,Red Alga ,Electron transfer ,Immobilization ,Fabrication ,Orientation ,Monolayer ,direct electron transfer ,Physical and Theoretical Chemistry ,QD1-999 ,Molecular Biology ,Photocurrent ,Graphene ,Organic Chemistry ,biophotovoltaics ,Proteins ,biology.organism_classification ,Recombination ,0104 chemical sciences ,chemistry - Abstract
Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.
- Published
- 2021
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27. Novel Copper Bearing Schiff Bases with Photodynamic Anti-Inflammatory and Anti-Microbial Activities
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Furkan Ayaz, Kasim Ocakoglu, Burcu Demirbag, and İlyas Gönül
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0106 biological sciences ,Staphylococcus aureus ,Gram-negative bacteria ,Light ,Cell Survival ,medicine.drug_class ,Gram-positive bacteria ,Anti-Inflammatory Agents ,chemistry.chemical_element ,Electrons ,Bioengineering ,Microbial Sensitivity Tests ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biochemistry ,Anti-inflammatory ,Inhibitory Concentration 50 ,Mice ,chemistry.chemical_compound ,Anti-Infective Agents ,010608 biotechnology ,Escherichia coli ,medicine ,Animals ,Molecular Biology ,Schiff Bases ,Bacteria ,biology ,010405 organic chemistry ,Macrophages ,Neomycin ,General Medicine ,biology.organism_classification ,Antimicrobial ,Combinatorial chemistry ,Copper ,In vitro ,Anti-Bacterial Agents ,0104 chemical sciences ,RAW 264.7 Cells ,chemistry ,Salicylic acid ,Biotechnology ,medicine.drug - Abstract
Schiff bases and their copper complexes have been previously studied for their anti-inflammatory, anti-tumor as well as anti-microbial activities. Schiff bases can be derivatized to gain photoluminiscence capacity. This property of the schiff bases enables the transfer of the electrons upon absorption of the light at a specific wavelength. In this study, we exploited this attribute of novel copper bearing schiff bases and tested their photodynamic biological activities. These compounds exerted photodynamic anti-inflammatory activities on the in vitro activated mammalian macrophages. Compared with salicylic acid control groups, these novel schiff bases had stronger activity which became more prominent with photo-induction. Moreover, they also had anti-microbial activity on gram negative bacteria E.coli and gram positive bacteria S.aureus.This anti-microbial activity was stronger than that of Neomycin on both bacterial strains. Our results suggest their potential use as anti-inflammatory and anti-microbial agents both in the dark as well as after photo-induction.
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- 2019
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28. Synthesis and antimicrobial photodynamic activities of axially {4-[(1E)-3-oxo-3-(2-thienyl)prop-1-en-1-yl]phenoxy} groups substituted silicon phthalocyanine, subphthalocyanine on Gram-positive and Gram-negative bacteria
- Author
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Ismail Ozturk, Kasim Ocakoglu, Ayça Tunçel, Zekeriya Bıyıklıoğlu, Fatma Yurt, Mine Hosgor-Limoncu, Tayfun Arslan, and Belirlenecek
- Subjects
Silicon ,Staphylococcus aureus ,Gram-negative bacteria ,Phthalocyanines ,General Chemical Engineering ,medicine.medical_treatment ,Radical ,Photodynamic therapy ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,chemistry.chemical_compound ,Escherichia coli ,medicine ,Molecule ,Photosensitizer ,Triplet state ,Antimicrobial photodynamic therapy ,biology ,Chemistry ,Singlet oxygen ,Process Chemistry and Technology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,Antimicrobial ,Combinatorial chemistry ,0104 chemical sciences ,0210 nano-technology - Abstract
Ocakoglu, Kasim/0000-0003-2807-0425; Biyiklioglu, Zekeriya/0000-0001-5138-214X; Tuncel, Ayca/0000-0003-0699-3309 WOS: 000466823300017 Today, the problem of antimicrobial resistance is the most important cause of morbidity and mortality in the treatment of infectious diseases worldwide. Therefore, alternative treatment strategies are important for controlling infectious diseases. In the basic principle of antimicrobial photodynamic therapy (aPDT), when harmless light at the appropriate wavelength absorbed by the photosensitizer, undergoes a transition from a ground state to a triplet state. The triplet state photosensitizer can interact with enzym and substrate molecules to produce free radicals and radical ions, or with molecular oxygen resulting in the generation of singlet oxygen which leads to cell cytotoxicity of the microorganism. For this purpose, axially {4-[(1E)-3-oxo-3-(2-thienyl) prop-1-en-1-yl] phenoxy} group substituted silicon phthalocyanine (Es-SiPc) and subphthalocyanine (Es-SubPc) were synthesized by reaction of SiPcCl2, SubPcCl with (2E)-3-(4-hydroxyphenyl)-1-(2-thienyl)prop-2-en-1-one in the presence of NaH in toluene. The new Es-SiPc and Es-SubPc were characterized by standard spectroscopy methods. The effects of aPDT in the presence of phthalocyanines were investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) strains. Also, singlet oxygen generation of Es-SiPc and Es-SubPc were investigated. Our results suggest that the aPDT in the presence of newly synthesized Es-SiPc and Es-SubPc has promising antibacterial effects on Gram-positive and Gram-negative bacteria.
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- 2019
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29. Subphthalocyanine as a fluorescence imaging agent for breast tumor
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Fatma Yurt, Osman Yilmaz, Ozge Er, Mine Ince, Kasim Ocakoglu, and Hale Melis Soylu
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Fluorescence-lifetime imaging microscopy ,Indoles ,Photosensitizing Agents ,Chemistry ,Optical Imaging ,Biophysics ,Mammary Neoplasms, Experimental ,Mice, Nude ,Cancer ,Dermatology ,Isoindoles ,medicine.disease ,Fluorescence ,Breast tumor ,High uptake ,Mice ,Oncology ,In vivo ,medicine ,Cancer research ,Animals ,Female ,Pharmacology (medical) - Abstract
Tri-tert-butyl-carboxyl subphthalocyanine (SubPc) was synthesized and evaluated as a fluorescence agent. Fluorescence imaging for breast tumor in vivo was performed using nude mice as models. Results indicate high uptake in tumor at 20 h. Tumor-non tumor ratio was determined as 2.25. The imaging results demonstrate the potential of this fluorescence-imaging agent in the diagnosis of breast tumor. In the future, subphthalocyanine is also developing as a dual functional, which is fluorescence imaging and as a photodynamic therapeutic agent for the treatment and diagnosis of cancer.
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- 2019
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30. Photo-induced anti-inflammatory activities of chloro substituted subphthalocyanines on the mammalian macrophage in vitro
- Author
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Furkan Ayaz, Mine Ince, Kasim Ocakoglu, and Naz Ugur
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Indoles ,medicine.drug_class ,030303 biophysics ,Biophysics ,Inflammation ,Dermatology ,Isoindoles ,Anti-inflammatory ,Cell Line ,Mice ,030207 dermatology & venereal diseases ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,medicine ,Animals ,Macrophage ,Pharmacology (medical) ,0303 health sciences ,Photosensitizing Agents ,Chemistry ,Macrophages ,Phototherapy ,In vitro ,Cell biology ,Oncology ,Lasers, Gas ,Cytokines ,Inflammation Mediators ,medicine.symptom ,Chlorine Compounds - Abstract
In this study, a series of subphthalocyanines (SubPcs) derivatives were synthesized to generate unique immunomodulatory molecules that can be activated through photo-induction. Immunomodulatory agents have a great potential in medicine to manipulate the immune system according to our needs and prevent disease symptoms. Inflammation is one of these symptoms and macrophages play a crucial role in the generation of inflammatory responses. Being able to control the activity of these agents through photo-induction enables the fine tuning on their activities in a location specific and non-invasive manner with possibly minor side effects. Mammalian macrophages' pro-inflammatory activity was examined in the presence of our compounds as well as LPS as a danger mimic. These compounds exerted photo-induced anti-inflammatory activities on the macrophages. Number of Cl atoms was a defining factor in their photo-induced anti-inflammatory immunomodulatory efficiencies.
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- 2019
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31. Development of antimicrobial nanocomposite scaffolds via loading CZTSe quantum dots for wound dressing applications
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Seda Ceylan, Buse Sert, Fatma Yurt, Ayça Tunçel, İsmail Öztürk, Didem Demir, and Kasim Ocakoglu
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cytocompatibility ,Chitosan ,antimicrobial activity ,Polymers ,Biomedical Engineering ,Biocompatible Materials ,Bioengineering ,Bandages ,Anti-Bacterial Agents ,Nanocomposites ,Antibacterial Activity ,Biomaterials ,Mice ,Anti-Infective Agents ,CZTSe QDs ,Polyvinyl Alcohol ,PVA ,Quantum Dots ,Solvents ,Animals ,Selenium Nanoparticles - Abstract
The antimicrobial properties of scaffolds designed for use in wound healing are accepted as an important factor in the healing process to accelerate the wound healing process without causing inflammation. For this purpose, chitosan–polyvinyl alcohol composite membranes loaded with Cu2ZnSnSe4 quantum dots (CZTSe QDs) as an antibacterial and cytocompatible biomaterial to regulate the wound healing process were produced. CZTSe QDs particles were synthesized under hydrothermal conditions. Polymer-based nanocomposites with different concentrations of the synthesized nanoparticles were produced by the solvent casting method. After detailed physicochemical and morphological characterizations of CZTSe QDs and composite membranes, antibacterial activities and cell viability were extensively investigated against gram-positive and gram-negative bacterial and yeast strains, and L929 mouse fibroblast cells lines, respectively. The results show that the preparation of composite scaffolds at a QDs concentration of 3.3% by weight has the best antimicrobial activity. Composite scaffold membranes, which can be obtained as a result of an easy production process, are thought to have great potential applications in tissue engineering as wound dressing material due to their high mechanical properties, wettability, strong antibacterial properties and non-toxicity.
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- 2022
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32. Nanoparticle additive fuels: Atomization, combustion and fuel characteristics
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Rıdvan Küçükosman, Ahmet Alper Yontar, and Kasim Ocakoglu
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Fuel Technology ,Analytical Chemistry - Published
- 2022
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33. Development of a Novel Nanoarchitecture of the Robust Photosystem I from a Volcanic Microalga
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Miriam, Izzo, Margot, Jacquet, Takayuki, Fujiwara, Ersan, Harputlu, Radosław, Mazur, Piotr, Wróbel, Tomasz, Góral, C Gokhan, Unlu, Kasim, Ocakoglu, Shinya, Miyagishima, and Joanna, Kargul
- Subjects
biohybrid nanodevices ,Light ,Photosystem I Protein Complex ,photosystem I ,Cyanidioschyzon merolae ,biophotovoltaics ,Article ,Nanostructures ,Rhodophyta ,Microalgae ,Graphite ,direct electron transfer ,Oxidation-Reduction ,Signal Transduction ,single layer graphene - Abstract
Here, we report the development of a novel photoactive biomolecular nanoarchitecture based on the genetically engineered extremophilic photosystem I (PSI) biophotocatalyst interfaced with a single layer graphene via pyrene-nitrilotriacetic acid self-assembled monolayer (SAM). For the oriented and stable immobilization of the PSI biophotocatalyst, an His6-tag was genetically engineered at the N-terminus of the stromal PsaD subunit of PSI, allowing for the preferential binding of this photoactive complex with its reducing side towards the graphene monolayer. This approach yielded a novel robust and ordered nanoarchitecture designed to generate an efficient direct electron transfer pathway between graphene, the metal redox center in the organic SAM and the photo-oxidized PSI biocatalyst. The nanosystem yielded an overall current output of 16.5 µA·cm−2 for the nickel- and 17.3 µA·cm−2 for the cobalt-based nanoassemblies, and was stable for at least 1 h of continuous standard illumination. The novel green nanosystem described in this work carries the high potential for future applications due to its robustness, highly ordered and simple architecture characterized by the high biophotocatalyst loading as well as simplicity of manufacturing.
- Published
- 2021
34. Enhancement of direct electron transfer in graphene bioelectrodes containing novel cytochrome c
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Miriam, Izzo, Silvio, Osella, Margot, Jacquet, Małgorzata, Kiliszek, Ersan, Harputlu, Alicja, Starkowska, Anna, Łasica, C Gokhan, Unlu, Tomasz, Uśpieński, Paweł, Niewiadomski, Dariusz, Bartosik, Bartosz, Trzaskowski, Kasim, Ocakoglu, and Joanna, Kargul
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Electron Transport ,Mutation ,Cytochrome c Group ,Graphite ,Amino Acid Sequence ,Heme ,Electrodes - Abstract
The highly efficient bioelectrodes based on single layer graphene (SLG) functionalized with pyrene self-assembled monolayer and novel cytochromec
- Published
- 2021
35. Enhanced bacterial uptake of I-131-labeled antimicrobial imidazolium bromide salts using fluorescent carbon nanodots
- Author
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Suleyman Gokhan Colak, Melis Ozge Alas, Rükan Genç, Kasim Ocakoglu, Ismail Ozturk, Fatma Yurt, Ayça Tunçel, Ali Niyazi Duman, Ozge Er, and Ege Üniversitesi
- Subjects
Materials science ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,chemistry.chemical_compound ,Bromide ,Materials Chemistry ,medicine ,Side chain ,Molecule ,Carbon dots ,General Materials Science ,Escherichia coli ,Alkyl ,chemistry.chemical_classification ,Radiolabelling ,Gram-positive bacteria ,021001 nanoscience & nanotechnology ,Fluorescence ,Combinatorial chemistry ,Naphthalimide ,0104 chemical sciences ,Imidazolium salts ,chemistry ,Mechanics of Materials ,Lipophilicity ,Antibacterial activity ,Nanocarriers ,0210 nano-technology - Abstract
Imidazolium bromide salts have been shown as potent antibiotic molecules that show structure-based bioactivity related to their cation alkyl side chain length. To enhance the bioavailability of lipophilic alkyl side chains herein, a 1,8-naphthalimide group containing imidazolium bromide salts bearing different lengths of alkyl chains (NIM1, 2, and 3) are coupled with fluorescent carbon dots (C-NIMs) through electrostatic and pi-pi interactions. Further, obtained nanocarriers were radio-labeled with iodine-131 (131I) to track the bacterial uptake of them by Staphylococcus aureus and Escherichia coli. Antibacterial activities were also investigated by the microdilution method. Comparison studies showed that both radiolabeling efficiency and lipophilicity increased when NIMs were integrated onto the CDots. More importantly, CDots resulted in 4-fold enhanced uptake of NIM1 by S. aureus bacterium as compared to pristine imidazolium bromide salts while at a higher number of alkyl chain lengths enhancement was 2-fold.
- Published
- 2021
36. Evaluation of photodynamic therapy and nuclear imaging potential of subphthalocyanine integrated TiO2 nanoparticles in mammary and cervical tumor cells
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Fatma Yurt, Kasim Ocakoglu, Ozge Er, Hale Melis Soylu, Mine Ince, Cıgır Biray Avci, Cansu Caliskan Kurt, Fatma Aslıhan Sarı, Suleyman Gokhan Colak, and Cumhur Gunduz
- Published
- 2021
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- View/download PDF
37. Synthesis of axially disubstituted silicon phthalocyanines and investigation of their in vitro cytotoxic/phototoxic anticancer activities
- Author
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Ayça Tunçel, Kasim Ocakoglu, Zekeriya Bıyıklıoğlu, Fatma Yurt, Derya Ozel, Ece Tuğba Saka, and Ege Üniversitesi
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Silicon phthalocyanine ,Silicon ,medicine.medical_treatment ,chemistry.chemical_element ,1 3 1 I ,Photodynamic therapy ,General Chemistry ,I-131 ,Combinatorial chemistry ,In vitro ,chemistry ,photodynamic therapy ,colon adenocarcinoma ,medicine ,Cytotoxic T cell ,silicon phthalocyanine ,Colon adenocarcinoma ,Phototoxicity - Abstract
In this study, two SiPcs have been selected and the photodynamic therapy potentials were evaluated of the Pcs. Synthesis of Axially 2-decyn-1-oxy disubstituted Es-SiPc-2 was newly synthesized by the reaction of SiPcCl2 with 2-decyn-1-ol in the presence of NaH in toluene. Furthermore, their nuclear imaging potentials were evaluated in human colon adenocarcinoma (HT-29) and human lung fibroblast cell (WI-38) cell lines. The uptake results have indicated that Es-SiPc labeled with [Formula: see text]I radionuclide ([Formula: see text]I-Es-SiPc) was approximately 2-fold higher in the HT-29 cell line than the WI-38 cell line. In other words, the target/non-target tissue ratio is defined as two in the HT-29/WI-38 cell lines. Besides, the uptake values of [Formula: see text]I-Es-SiPc were found to be higher than [Formula: see text]I-Es-SiPc-2. [Formula: see text]I-Es-SiPc and [Formula: see text]I-Es-SiPc-2 are promising for imaging or treating colon adenocarcinoma. In vitrophotodynamic therapy (PDT) studies have shown that both compounds are suitable and can be used in this field. Also, Es-SiPc has been shown to have higher phototoxicity than Es-SiPc-2.
- Published
- 2021
38. Antimicrobial photodynamic therapy against Staphylococcus aureus using zinc phthalocyanine and zinc phthalocyanine-integrated TiO2 nanoparticles
- Author
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Ayça Tunçel, Ismail Öztürk, Mine Ince, Kasim Ocakoglu, Mine Hoşgör-Limoncu, and Fatma Yurt
- Published
- 2021
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39. Subphthalocyanine-sensitized TiO
- Author
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A, Celil Yüzer, Eminegül, Genc, Ersan, Harputlu, Gizem, Yanalak, Emre, Aslan, Kasim, Ocakoglu, Imren, Hatay Patir, and Mine, Ince
- Abstract
A series of SubPcs comprising a carboxylic acid anchoring group at the peripheral (SubPcs 1, 2) or axial position (SubPc 3) were synthesized and used as sensitizers for photocatalytic H2 production, for the first time. SubPc 3/TiO2 shows the best photocatalytic activity with a hydrogen evolution rate of 1396 μmol h-1, which is much higher than that of SubPcs 1 and 2 (771 and 658 μmol g-1, respectively). This work clearly shows that considering their optical and redox properties, SubPcs are promising candidates for light-driven water splitting systems.
- Published
- 2020
40. Radiolabeling, In Vitro Cell Uptake, and In Vivo Photodynamic Therapy Potential of Targeted Mesoporous Silica Nanoparticles Containing Zinc Phthalocyanine
- Author
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Ayça Tunçel, Kasim Ocakoglu, Osman Yilmaz, Efsun Kolatan, Mine Ince, Safiye Aktaş, Ozge Er, Fatma Yurt, and Ege Üniversitesi
- Subjects
Necrosis ,medicine.medical_treatment ,Pharmaceutical Science ,Photodynamic therapy ,02 engineering and technology ,030226 pharmacology & pharmacy ,singlet oxygen ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,In vivo ,Pancreatic cancer ,Drug Discovery ,cetuximab ,medicine ,mesoporous silica nanoparticles ,Singlet oxygen ,Mesoporous silica ,021001 nanoscience & nanotechnology ,medicine.disease ,Molecular biology ,In vitro ,Zn(II) phthalocyanine ,chemistry ,photodynamic therapy ,Molecular Medicine ,medicine.symptom ,0210 nano-technology ,Intracellular - Abstract
Photodynamic therapy (PDT) is a noninvasive therapy based on the photodynamic effect. in this study, we sought to determine intracellular uptake and in vivo photodynamic therapy potential of Zn phthalocyanine-loaded mesoporous silica nanoparticles (MSNPS) against pancreatic cancer cells. MSNPS were labeled with I-131; the radiolabeling efficiency was found to 95.5 +/- 1.2% in pH 9 and 60 min reaction time. Besides, the highest intracellular uptake yields of I-131-MSNPS nanoparticles in MIA PaCa-2, AsPC-1, and PANC-1 cells were determined as 43.9 +/- 3.8%, 41.8 +/- 0.2%, and 37.9 +/- 1.3%, respectively, at 24 h incubation time. in vivo PDT studies were performed with subcutaneous xenograft cancer model nude mice with AsPC-1 pancreatic cancer cells. For photodynamic therapy, 685 nm red laser light 100 J/cm(2) light dose using and 5-20 mu M ZnPc containing MSNPS concentrations were applied. Histopathological studies revealed that the ratio of necrosis in tumor tissue was higher in the treatment group than the control groups., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [2214/A]; Ege University, Scientific Research Project (BAP)Ege University [16 NBE 001], This research was funded by the Scientific and Technological Research Council of Turkey (TUBITAK; grant number2214/A), Ege University, Scientific Research Project (BAP; grant Number: 16 NBE 001).
- Published
- 2020
41. Radiolabeling
- Author
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Ozge, Er, Ayca, Tuncel, Kasim, Ocakoglu, Mine, Ince, Efsun Hatice, Kolatan, Osman, Yilmaz, Safiye, Aktaş, and Fatma, Yurt
- Subjects
Male ,Indoles ,Photosensitizing Agents ,Light ,Lasers ,Cetuximab ,Metal Nanoparticles ,Mice, Nude ,Hydrogen-Ion Concentration ,Isoindoles ,Silicon Dioxide ,Combined Modality Therapy ,Xenograft Model Antitumor Assays ,Iodine Radioisotopes ,Pancreatic Neoplasms ,Mice ,Necrosis ,Antineoplastic Agents, Immunological ,Photochemotherapy ,Zinc Compounds ,Cell Line, Tumor ,Organometallic Compounds ,Animals ,Humans ,Nanoparticles - Abstract
Photodynamic therapy (PDT) is a noninvasive therapy based on the photodynamic effect. In this study, we sought to determine intracellular uptake and
- Published
- 2020
42. Investigation of in vitro biological activities of hollow mesoporous carbon nanoparticles bearing D-NMAPPD on human lung adenocarcinoma cells
- Author
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Fatih Mehmet Emen, Canan Vejselova Sezer, Ruken Esra Demirdogen, Naz Ugur, Ersan Harputlu, Fatma Yurt, Hatice Mehtap Kutlu, Kasim Ocakoglu, Mine Ince, and C. Gokhan Unlu
- Subjects
hollow mesoporous carbon nanoparticle ,Cytotoxicity ,Pharmaceutical Science ,Nanoparticle ,IC50 ,confocal microscopy ,carbon nanoparticle ,law.invention ,law ,Tumor-Growth ,antineoplastic agent ,drug release ,Cancer ,Chemistry ,drug cytotoxicity ,apoptosis ,Fourier transform infrared spectroscopy ,field emission scanning electron microscopy ,unclassified drug ,Transmission electron microscopy ,A-549 cell line ,D-NMAPPD ,Lung cancer ,Delivery ,Nanospheres ,antiproliferative activity ,cell ultrastructure ,Thermogravimetric analysis ,in vitro study ,chromatin condensation ,biological activity ,antineoplastic activity ,Article ,Confocal microscopy ,transmission electron microscopy ,ceramide derivative ,controlled study ,human ,1 (4' nitrophenyl) 2 (tetradecanoylamido) 1,3 propanediol ,cell viability ,B13 ,human cell ,Hollow mesoporous carbon nanoparticles ,lung adenocarcinoma ,In vitro ,immobilization ,Ultrastructure ,Electron microscope ,Analogs ,Nuclear chemistry - Abstract
The uniformly dispersed hollow mesoporous carbon nanoparticles (HMCNPs) were successfully synthesized by hard-template methods, and D-NMAPPD (B13) was successfully loaded onto the nanoparticle surface for the first time. Structural properties of bare and B13 loaded HMCNPs (HMCNs-B-13) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission-Scanning Electron Microscopy (FE-SEM), Thermal Gravimetric Analysis (TG). The amount of drug released was determined via in vitro drug release studies at 37 °C in SBF through UV–Vis spectrometric and thermal analyses. TG data revealed that the proportion of loaded B-13 was 33.60%. Their ability to induce apoptosis in cultures of A549 human lung adenocarcinoma cells was investigated, and the inhibitory effect of HMCNPs-B-13 on lung cancer cell proliferation was determined in vitro. The IC50 values determined after application periods of 24 and 48 h were found to be 16.13 ?g/mL and 12.96 ?g/mL, respectively. The role of HMCNPs-B-13 on the morphology and ultrastructure of A549 cells was also investigated by confocal microscopy and Transmission electron microscopy (TEM) studies. © 2021 Elsevier B.V.
- Published
- 2022
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43. Photodynamic therapy and nuclear imaging activities of SubPhthalocyanine integrated TiO2 nanoparticles
- Author
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Ozge Er, Cigir Biray Avci, Cumhur Gündüz, Kasim Ocakoglu, Mine Ince, Fatma Aslıhan Sarı, Cansu Caliskan Kurt, Fatma Yurt, Hale Melis Soylu, and Suleyman Gokhan Colak
- Subjects
Chemistry ,Nuclear imaging ,General Chemical Engineering ,medicine.medical_treatment ,Tio2 nanoparticles ,General Physics and Astronomy ,Photodynamic therapy ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease ,Colon tumors ,01 natural sciences ,digestive system diseases ,In vitro ,0104 chemical sciences ,Hepatocellular carcinoma ,medicine ,Cancer research ,Colorectal adenocarcinoma ,0210 nano-technology ,Liver cancer - Abstract
In this study, Subphthalocyanine (SubPc) and SubPc integrated TiO2 nanoparticles (SubPc- TiO2) were examined as theranostic agents. In vitro photodynamic therapy (PDT) efficiency of SubPc/SubPc-TiO2 and nuclear imaging potential of 131I labeled SubPc/TiO2-SubPc were determined on hepatocellular carcinoma (HepG2), colorectal adenocarcinoma (HT29) and human healthy lung (WI38) cell lines. As a result, 131I-SubPc and 131I-SubPc-TiO2 have been identified as a nuclear imaging agent for liver cancer. Additionally, 131I-SubPc-TiO2 has been found to be promising for imaging colon tumors. According to the in vitro photodynamic therapy studies, SubPc and SubPc-TiO2 were determined suitable PDT agents for liver and colon tumors. These results suggest that SubPc-TiO2 might be a theranostic agent with both PDT and nuclear imaging potential.
- Published
- 2018
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44. Antibacterial properties of subphthalocyanine and subphthalocyanine-TiO2 nanoparticles on Staphylococcus aureus and Escherichia coli
- Author
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Mine Hosgor-Limoncu, Ayça Tunçel, Fatma Yurt, Ismail Ozturk, Mine Ince, and Kasim Ocakoglu
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010405 organic chemistry ,Chemistry ,Tio2 nanoparticles ,Treatment options ,General Chemistry ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,0104 chemical sciences ,Microbiology ,Antibiotic resistance ,Staphylococcus aureus ,medicine ,Escherichia coli - Abstract
Nowadays the problem of antimicrobial resistance is the most important cause of morbidity and mortality in the treatment of infectious diseases worldwide. Treatment options for antimicrobial-resistant microorganisms are quite limited. Therefore, alternative treatment strategies are needed to control infectious diseases. Antimicrobial photodynamic therapy (aPDT) is one of the new treatment modalities proposed for a wide variety of infections. In the basic principle of aPDT, photosensitizers (PS) produce free radicals by irradiating them with harmless light at the appropriate wavelength, and this causes microorganism cell cytotoxicity. In this study, light emitting diodes (LED) (630–700 nm, 17.4 mW/cm[Formula: see text] were used on Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Escherichia coli (E. coli) at different light doses under the minimum inhibitory concentration (MIC) values of SubPc and SubPc-integrated TiO2 nanoparticles (SubPc-TiO[Formula: see text] concentration. Both compounds show good phototoxicity toward S. aureus when high light doses (16, 24[Formula: see text]J/cm[Formula: see text] were applied. In addition, SubPc-TiO2 were found to be more effective than SubPc in aPDT of S. aureus. In E. coli, the success of aPDT has been shown to be dependent on the increased light dose (20, 30[Formula: see text]J/cm[Formula: see text] for both compounds. As a result, the aPDT activity of SubPc-TiO2 is more effective than SubPc in increasing light doses.
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- 2018
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45. Heterogeneous Electrocatalysts for Efficient Water Oxidation Derived from Metal Phthalocyanine
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Farhat Yasmeen, Mine Ince, Noor Ul Ain Babar, Suleyman Gokhan Colak, Khurram Saleem Joya, Kasim Ocakoglu, Sehrish Ikram, Syeda Robina Gilani, and Muhammad Sarfaraz
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02 engineering and technology ,General Chemistry ,Overpotential ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrocatalyst ,01 natural sciences ,0104 chemical sciences ,Catalysis ,Metal ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,visual_art ,visual_art.visual_art_medium ,Phthalocyanine ,0210 nano-technology ,Current density - Published
- 2018
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46. Preparation and evaluation of effect onEscherichia coliandStaphylococcus aureusof radiolabeled ampicillin-loaded graphene oxide nanoflakes
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Kasim Ocakoglu, Fatma Yurt, Onur Alp Ersoz, and Ersan Harputlu
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Staphylococcus aureus ,Scanning electron microscope ,Reducing agent ,Oxide ,02 engineering and technology ,010402 general chemistry ,medicine.disease_cause ,01 natural sciences ,Biochemistry ,law.invention ,chemistry.chemical_compound ,law ,Ampicillin ,Spectroscopy, Fourier Transform Infrared ,Drug Discovery ,Escherichia coli ,medicine ,Fourier transform infrared spectroscopy ,Pharmacology ,Drug Carriers ,Graphene ,Chemistry ,Organic Chemistry ,Organotechnetium Compounds ,021001 nanoscience & nanotechnology ,Anti-Bacterial Agents ,Nanostructures ,0104 chemical sciences ,Isotope Labeling ,Molecular Medicine ,Graphite ,0210 nano-technology ,medicine.drug ,Nuclear chemistry - Abstract
Ampicillin is a one of effective antibiotics against Gram-positive and Gram-negative bacteria. This study aimed to label ampicillin-loaded graphene oxide nanoflake (AMP-GO) with 99m Tc and evaluate of its in vitro binding to Staphylococcus aureus and Escherichia coli. Firstly, ampicillin was loaded into graphene oxide nanoflake prepared. AMP-GO was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) techniques, and the amount of loaded ampicillin onto GO was determined by UV-Vis absorption spectroscopy. AMP and AMP-GO were labeled with 99m Tc using stannous chloride reducing agent. Labeling efficiency of 99m Tc-AMP-GO was found to be 97.66 ± 2.06%. 99m Tc-AMP-GO has higher binding efficiencies to both S. aureus and E. coli than 99m Tc-AMP. 99m Tc-AMP-GO could be promising candidate as agent infection nuclear imaging. Furthermore, in vivo studies of 99m Tc-AMP-GO with infected rats are planned to be performed.
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- 2018
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47. Green Nanotechnology for Synthesis and characterization of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) nanoparticles for sustained bortezomib release using supercritical CO2 assisted particle formation combined with electrodeposition
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Fatih Mehmet Emen, Kasim Ocakoglu, Gokturk Avsar, Ruken Esra Demirdogen, Paramasivam Murugan, and Kumar Sudesh
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Materials science ,Green nanotechnology ,Bortezomib ,Size-exclusion chromatography ,Nanoparticle ,02 engineering and technology ,General Medicine ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Biochemistry ,Supercritical fluid ,0104 chemical sciences ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,Structural Biology ,Carbon dioxide ,medicine ,Organic chemistry ,Particle ,0210 nano-technology ,Electroplating ,Molecular Biology ,medicine.drug - Abstract
Carbon dioxide assisted particle formation combined with electrospraying using supercritical CO2 (scCO2) as an aid (Carbon Dioxide Assisted Nebulization-Electrodeposition, CAN-ED) was used to produce Bortezomib loaded poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) P(3HB-co-3HHx) nanoparticles for sustained release. The morphology and structure of the prepared nanoparticles were investigated by SEM, TEM and FT-IR spectroscopy. Average diameter of particles obtained was 155nm and the average core sizes of P(3HB-co-3HHx) nanoparticles were between 6 and 13nm. The drug loading capacity, drug release and stability of Bortezomib loaded P(3HB-co-3HHx) nanoparticles were analyzed. The maximum loading capacity was achieved at pH=6.0 in phosphate buffer (K2HPO4/KH2PO4). It was found that temperature did not affect the stability of Bortezomib loaded nanoparticles and it was good both at 37°C and 4°C. This study pointed out that CAN-ED is a green method to produce P(3HB-co-3HHx) nanoparticles for pH responsive targeting of Bortezomib especially to parts of the body where size exclusion is not crucial.
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- 2018
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48. Evaluation of infection imaging potential of 131I-labeled imidazolium salt
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Fatma Yurt, Kasim Ocakoglu, Suleyman Gokhan Colak, Ayça Tunçel, Ismail Ozturk, and Osman Yilmaz
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Biodistribution ,medicine.drug_class ,Health, Toxicology and Mutagenesis ,Microorganism ,Antibiotics ,Salt (chemistry) ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Analytical Chemistry ,Microbiology ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,medicine ,Radiology, Nuclear Medicine and imaging ,Infection imaging ,Spectroscopy ,chemistry.chemical_classification ,Public Health, Environmental and Occupational Health ,Antimicrobial ,Pollution ,In vitro ,0104 chemical sciences ,Nuclear Energy and Engineering ,chemistry ,030220 oncology & carcinogenesis - Abstract
Effective antimicrobial compounds are necessary due to increased resistance of antibiotics against microorganisms causing infectious diseases. In this study, imidazolium-TFSI salt [ITFSI: octyl-bis(3-methylimidazolium)-di(bis(trifluoromethane)sulfonimide)] was labeled with I-131 with high efficiency. In vitro uptake experiments of I-131-ITFSI showed high uptake in gram-positive Staphylococcus aureus bacteria. I-131-ITFSI was also evaluated for comparison between bacterial infection and sterile inflammation by in vivo studies. The biodistribution results revealed that I-131-ITFSI might be used as a nuclear imaging agent for detection of bacterial infection.
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- 2018
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49. Synergetic effects of Fe3+ doped spinel Li4Ti5O12 nanoparticles on reduced graphene oxide for high surface electrode hybrid supercapacitors
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Nora Kremer, Ralf Thomann, Seda Gurgen, Ersan Harputlu, Fatih Mehmet Emen, Stefan Weber, Mike Castellano, Nils Pompe, Kasim Ocakoglu, Emre Erdem, Jakob Wörner, Anke Hoffmann, and Sergej Repp
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Supercapacitor ,Materials science ,Graphene ,Oxide ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Dielectric spectroscopy ,Thermogravimetry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Ionic conductivity ,General Materials Science ,Thermal stability ,0210 nano-technology ,Lithium titanate - Abstract
In this work, reduced graphene oxide (rGO) based electrode materials were developed to achieve a hybrid supercapacitor (SC) function. Therefore, several synthesis methods were developed to prepare a cost effective and environmentally friendly rGO. Additionally, to maintain the high surface area, spinel lithium titanate (sLTO) nanoparticles (NPs) were synthesized and deposited on the rGO surface to inhibit the restacking of the rGO layers on graphite. Furthermore, the adequate Fe-doping of sLTO increased the ionic conductivity and the intercalation capacity, which is necessary for a SC performance. The sLTO/rGO-composites were electrochemically analysed by chronopotentiometry and electrochemical impedance spectroscopy (EIS) to determine the stability during charge/discharge cycling and the capacity, respectively. To overcome the drawback of LTO's low conductivity values, its value has been drastically increased by Fe-doping. The results demonstrated the remarkable cycling performance of the Fe:LTO/rGO composite as well as a higher capacity compared to LTO/rGO and pure rGO-electrodes. The thermal stability, degradation and weight loss of the sLTO/rGO in the temperature range between 20 °C and 800 °C were investigated by thermogravimetry (TG)/DTA. As a conclusion, it can be stated that, increasing the ionic conductivity by Fe-doping drastically increases the hybrid capacity of the SC electrodes.
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- 2018
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50. Synthesis and characterization of composite catalysts comprised of ZnO/MoS2/rGO for photocatalytic decolorization of BR 18 dye
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Nadir Dizge, Kasim Ocakoglu, Naz Ugur, and Zeynep Bilici
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Materials science ,Band gap ,Graphene ,Oxide ,Heterojunction ,Context (language use) ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,chemistry ,Chemical engineering ,law ,Photocatalysis ,Nanorod ,0210 nano-technology ,Hybrid material - Abstract
In recent years, photocatalysis upon semiconductor-based hybrid materials has received much attention for the improved environmental effects and energy applications. Many good semiconductors such as ZnO have large bandgaps and suffer from fast charge recombination which hinders photocatalytic activity. One possible strategy to overcome this problem is introducing a narrow bandgap co-catalyst. Within the context of this study, triple hybrid nanostructures comprised of ZnO nanorods and MoS2/rGO (MG) co-catalyst were synthesized and characterized by various analytical methods. Accordingly, 25ZnO/75MG and 75ZnO/25MG hybrid materials were synthesized for two different MG co-catalyst comprised of 0.5% (named as 25ZnO/75MG1) and 5% (named as 25ZnO/75MG2) graphene oxide. The photocatalytic activities of the heterostructures and pristine ZnO nanorods were evaluated by the degradation of BR 18 dye, a common water pollutant mainly from the textile industry. When introduced with the co-catalyst, 25ZnO/75MG1 heterostructures achieved 100% degradation for 180 min. Furthermore, when the GO amount in the co-catalyst was increased to 5%, fully degradation of the dye solution was realized by 25ZnO/75MG2 in the first 30 min. These results are indicative of a positive synergistic effect of MoS2-rGO co-catalyst. Also, it is shown that increasing the GO amount is an effective approach to accelerate charge separation and electron transport properties.
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- 2021
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