PubMed İndeksli Yayınlar Koleksiyonu / PubMed Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7645
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Article Citation - WoS: 1Citation - Scopus: 1Ferromagnetism Above 200 K in Organic-Ion Intercalated CrSBr(American Chemical Society, 2025) Ferreira-Teixeira, S.; Tezze, D.; Ramos, M.; Álvarez-García, C.; Bayındır, B.; Jo, J.; Gobbi, M.CrSBr is a van der Waals magnetic semiconductor exhibiting antiferromagnetic order below 140 K. It has emerged as a promising platform for engineering 2D magnetism because its intertwined electronic, optical, and magnetic properties can be profoundly modified via external stimuli such as electrical gating or magnetic fields. However, other strategies for tuning magnetism in layered materials, such as molecular intercalation, remain largely unexplored for CrSBr. Here, we demonstrate that the intercalation of tetramethylammonium (TMA) and tetrapropylammonium (TPA) ions into CrSBr induces a transition from antiferromagnetic to ferromagnetic order, while significantly enhancing the magnetic transition temperature to 190 K (TMA) and 230 K (TPA). The resulting intercalates are air-stable and exhibit large, hysteretic magnetoresistance exceeding 60% at 50 K in the TPA case. Besides, intercalation introduces symmetry-breaking structural changes in each CrSBr plane, revealed by Raman microscopy and corroborated by density functional theory (DFT) calculations. These findings highlight molecular intercalation as a powerful and versatile route to tailor the magnetic properties of CrSBr and unlock its potential to fabricate robust, high-temperature 2D magnetic devices. © 2025 Elsevier B.V., All rights reserved.Article Silver-Loaded Titania-Based Metal-Organic Frameworks as a Platform for Silver Ion Release for Antibacterial Applications(American Chemical Society, 2025) Mazare, Anca; Goldmann, Wolfgang Heinrich; Kocak, Esra; Osuagwu, Benedict; Qin, Shanshan; Cao, Ran; Schmuki, PatrikConventional Ag-decorated TiO<inf>2</inf>coatings suffer from low adsorption capacity and burst release kinetics, limiting long-term antibacterial efficacy and risking cytotoxicity. An entirely different payload release approach can be based on metal–organic frameworks (MOFs), which offer tunable porosity, high surface area, and internal diffusion channels. Here, we report a thermally stabilized Ti-based MOF [NH<inf>2</inf>-MIL-125(Ti)] functionalized with Ag+via reactive deposition, enabling high Ag loading (∼14.7 wt %) and sustained release. Annealing at 250 °C enhances aqueous stability, allowing diffusion-governed Ag+delivery over >48 h, with 77% of the Ag still present in the MOF after a 24 h release. The system exhibits dose-dependent antibacterial activity in powders and comparable efficacy in coatings, with a more gradual release profile. This scalable platform is promising for long-acting coatings, wound interfaces, and implantable materials. © 2025 Elsevier B.V., All rights reserved.Review Citation - WoS: 41Citation - Scopus: 43Electrochemical Sensors in the Food Sector: a Review(American Chemical Society, 2024) Ghaani, Masoud; Azimzadeh, Mostafa; Büyüktaş, Duygu; Carullo, Daniele; Farris, StefanoIn a world that is becoming increasingly concerned with health, safety, and the sustainability of food supply chains, the control and assurance of food quality have become of utmost importance. This review examines the application and potential of electrochemical sensors in the dynamic field of food science to meet these expanding demands. The article introduces electrochemical sensors and describes their operational mechanics and the components contributing to their function. A summary of the most prevalent electrochemical methods outlines the diverse food analysis techniques available. The review shifts to discussing the food science applications of these sensors, highlighting their crucial role in detecting compounds in food samples like meat, fish, juice, and milk for contemporary quality control. This paper showcases electrochemical sensors' utility in food analysis, underscoring their significance as powerful, efficient tools for maintaining food safety and how they could transform our approach to global food quality control and assurance.Review Citation - WoS: 14Citation - Scopus: 8Recent Progress on Synthesis and Properties of Black Phosphorus and Phosphorene as New-Age Nanomaterials for Water Decontamination(American Chemical Society, 2023) Goren,A.; Gungormus,E.; Vatanpour,V.; Yoon,Y.; Khataee,A.Concerted efforts have been made in recent years to find solutions to water and wastewater treatment challenges and eliminate the difficulties associated with treatment methods. Various techniques are used to ensure the recycling and reuse of water resources. Owing to their excellent chemical, physical, and biological properties, nanomaterials play an important role when integrated into water/wastewater treatment technologies. Black phosphorus (BP) is a potential nanomaterial candidate for water and wastewater treatment, especially its monolayer 2D derivative called phosphorene. Phosphorene offers relative adjustability in its direct bandgap, high charge carrier mobility, and improved in-plane anisotropy compared to the most extensively studied 2D nanomaterials. In this study, we examined the physical and chemical characteristics and synthetic processes of BP and phosphorene. We provide an overview of the latest advancements in the main applications of BP and phosphorene in water/wastewater treatment, which are categorized as photocatalytic, adsorption, and membrane filtration processes. Additionally, we explore the existing difficulties in the integration of BP and phosphorene into water/wastewater treatment technologies and prospects for future research in this field. In summary, this review highlights the ongoing necessity for significant research efforts on the integration of BP and phosphorene in water and wastewater applications. © 2024 American Chemical Society.Article Citation - WoS: 2Citation - Scopus: 2Plasmonic Functional Assay Platform Determines the Therapeutic Profile of Cancer Cells(American Chemical Society, 2023) Çetin, Arif E.; Topkaya, Seda Nur; Yazıcı, Ziya Ata; Yalçın Özuysal, ÖzdenFunctional assay platforms could identify the biophysicalpropertiesof cells and their therapeutic response to drug treatments. Despitetheir strong ability to assess cellular pathways, functional assaysrequire large tissue samples, long-term cell culture, and bulk measurements.Even though such a drawback is still valid, these limitations didnot hinder the interest in these platforms for their capacity to revealdrug susceptibility. Some of the limitations could be overcome withsingle-cell functional assays by identifying subpopulations usingsmall sample volumes. Along this direction, in this article, we developeda high-throughput plasmonic functional assay platform to identifythe growth profile of cells and their therapeutic profile under therapiesusing mass and growth rate statistics of individual cells. Our technologycould determine populations' growth profiles using the growthrate data of multiple single cells of the same population. Evaluatingspectral variations based on the plasmonic diffraction field intensityimages in real time, we could simultaneously monitor the mass changefor the cells within the field of view of a camera with the capacityof > & SIM;500 cells/h scanning rate. Our technology could determinethe therapeutic profile of cells under cancer drugs within few hours,while the classical techniques require days to show reduction in viabilitydue to antitumor effects. The platform could reveal the heterogeneitywithin the therapeutic profile of populations and determine subpopulationsshowing resistance to drug therapies. As a proof-of-principle demonstration,we studied the growth profile of MCF-7 cells and their therapeuticbehavior to standard-of-care drugs that have antitumor effects asshown in the literature, including difluoromethylornithine (DFMO),5-fluorouracil (5-FU), paclitaxel (PTX), and doxorubicin (Dox). Wesuccessfully demonstrated the resistant behavior of an MCF-7 variantthat could survive in the presence of DFMO. More importantly, we couldprecisely identify synergic and antagonistic effects of drug combinationsbased on the order of use in cancer therapy. Rapidly assessing thetherapeutic profile of cancer cells, our plasmonic functional assayplatform could be used to reveal personalized drug therapies for cancerpatients.Article Citation - WoS: 15Citation - Scopus: 14Electroactive Nanogel Formation by Reactive Layer-By Assembly of Polyester and Branched Polyethylenimine Via Aza-Michael Addition(American Chemical Society, 2021) Yıldırımkaraman, Öykü; Özenler, Sezer; Günay, Ufuk Saim; Durmaz, Hakan; Yıldız, Ümit HakanWe here demonstrate the utilization of reactive layer-by-layer (rLBL) assembly to form a nanogel coating made of branched polyethylenimine (BPEI) and alkyne containing polyester (PE) on a gold surface. The rLBL is generated by the rapid aza-Michael addition reaction of the alkyne group of PE and the -NH2 groups of BPEI by yielding a homogeneous gel coating on the gold substrate. The thickness profile of the nanogel revealed that a 400 nm thick coating is formed by six multilayers of rLBL, and it exhibits 50 nm roughness over 8 mu m distance. The LBL characteristics were determined via depth profiling analysis by X-ray photoelectron spectroscopy, and it has been shown that a 70-100 nm periodic increase in gel thickness is a consequence of consecutive cycles of rLBL. A detailed XPS analysis was performed to determine the yield of the rLBL reaction: the average yield was deduced as 86.4% by the ratio of the binding energies at 286.26 eV, (C CN-C bond) and 283.33 eV, (C C triple bond). The electrochemical characterization of the nanogels ascertains that up to the six-multilayered rLBL of BPEI-PE is electroactive, and the nanogel permeability had led to drive mass and charge transfer effectively. These results promise that nanogel formation by rLBL films may be a straightforward modification of electrodes approach, and it exhibits potential for the application of soft biointerfaces.Article Citation - WoS: 2Citation - Scopus: 3Transport Modeling of Locally Photogenerated Excitons in Halide Perovskites(American Chemical Society, 2021) Tang, Kuen Wai; Li, Senlei; Weeden, Spencer; Song, Ziyi; McClintock, Luke; Xiao, Rui; Senger, Ramazan TuğrulExcitons have fundamental impacts on optoelectronic properties of semiconductors. Halide perovskites, with long carrier lifetimes and ionic crystal structures, may support highly mobile excitons because the dipolar nature of excitons suppresses phonon scattering. Inspired by recent experimental progress, we perform device modeling to rigorously analyze exciton formation and transport in methylammonium lead triiodide under local photoexcitation by using a finite element method. Mobile excitons, coexisting with free carriers, can dominate photocurrent generation at low temperatures. The simulation results are in excellent agreement with the experimentally observed strong temperature and gate dependence of carrier diffusion. This work signifies that efficient exciton transport can substantially influence charge transport in the family of perovskite materials.Article Citation - WoS: 9Citation - Scopus: 11Pcr-Free Methodology for Detection of Single-Nucleotide Polymorphism With a Cationic Polythiophene Reporter(American Chemical Society, 2021) Yücel, Müge; Koç, Altuğ; UÜgenalp, Ayfer; Akkoç, Gün Deniz; Ceyhan, Metin; Yıldız, Ümit HakanThis study presents a nonamplification-based nucleic acid assay for the detection of single-nucleotide polymorphism (SNP) associated with familial Mediterranean fever (FMF) besides polymerase chain reaction (PCR)-based methodologies. The major objective is to show the potential of the proposed assay for rapid screening of FMF in a Mediterranean region of 400 million population. The assay relies on binding difference of specially designed wild and mutant primers to the target genomic DNA, followed by determination of unbound primers by quick titration of a cationic polythiophene reporter. The fluorescent reporter exhibits signal transition from 525 to 580 nm in the presence of unbound primers, and it correlates the binding affinity of label-free primers to the homozygous wild and mutant genomes. As a proof of concept, 26 real samples are studied relying on the ON and OFF fluorescence signals of the cationic polythiophene reporter. The results are analyzed by principal component analysis (PCA), which provides clear separation of healthy and patient individuals. The further analysis by support vector machine (SVM) classification has revealed that our assay converges to 96% overall accuracy. These results support that the PCR-free nucleic acid assay has a significant potential for rapid and cost-effective screening of familial Mediterranean fever.Article Citation - WoS: 16Citation - Scopus: 13Fabrication of Tunable 3d Cellular Structures in High Volume Using Magnetic Levitation Guided Assembly(American Chemical Society, 2021) Onbas, Rabia; Arslan Yıldız, AhuTunable and reproducible size with high circularity is an important limitation to obtain three-dimensional (3D) cellular structures and spheroids in scaffold free tissue engineering approaches. Here, we present a facile methodology based on magnetic levitation (MagLev) to fabricate 3D cellular structures rapidly and easily in high-volume and low magnetic field. In this study, 3D cellular structures were fabricated using magnetic levitation directed assembly where cells are suspended and self-assembled by contactless magnetic manipulation in the presence of a paramagnetic agent. The effect of cell seeding density, culture time, and paramagnetic agent concentration on the formation of 3D cellular structures was evaluated for NIH/3T3 mouse fibroblast cells. In addition, magnetic levitation guided cellular assembly and 3D tumor spheroid formation was examined for five different cancer cell lines: MCF7 (human epithelial breast adenocarcinoma), MDA-MB-231 (human epithelial breast adenocarcinoma), SHSYSY (human bone-marrow neuroblastoma), PC-12 (rat adrenal gland pheochromocytoma), and HeLa (human epithelial cervix adenocarcinoma). Moreover, formation of a 3D coculture model was successfully observed by using MDA-MB-231 dsRED and MDA-MB-231 GFP cells. Taken together, these results indicate that the developed MagLev setup provides an easy and efficient way to fabricate 3D cellular structures and may be a feasible alternative to conventional methodologies for cellular/multicellular studies.Article Citation - WoS: 111Stabilization of Magnetic Iron Oxide Nanoparticles in Biological Media by Fetal Bovine Serum (fbs)(American Chemical Society, 2011) Wiogo, Hilda T. R.; Lim, May; Bulmuş, Volga; Yun, Jimmy; Amal, RoseA facile method of stabilizing magnetic iron oxide nanoparticles (MNPs) in biological media (RPMI-1640) via surface modification with fetal bovine scrum (FBS) is presented herein. Dynamic light scattering (DLS) shows that the size of the MNP aggregates can be maintained at 190 +/- 2 nm for up to 16 h in an RPMI 1640 culture medium containing >= 4 vol % FBS. Under transmission electron microscopy (TEM), a layer of protein coating is observed to cover the MNP surface following treatment with FBS. The adsorption of proteins is further confirmed by X-ray photoelectron spectroscopy (XPS). Gel electrophoresis and LC-MS/MS studies reveal that complement factor I-I, antithrombin, complement factor I, alpha-1-antiproteinase, and apolipoprotein E are the proteins most strongly attached to the surface of all MNP. These surface-adsorbed proteins serve as a linker that aids the adsorption of other serum proteins, such as albumin, which otherwise adsorb poorly onto MNPs. The size stability of FBS-treated MNPs in biological media is attributed to the secondary adsorbed proteins, and the size stability in biological media can be maintained only when both the surface-adsorbed proteins and the secondary adsorbed proteins are present on the particle's surface.