Chemistry / Kimya

Permanent URI for this collectionhttps://hdl.handle.net/11147/4072

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Citation - WoS: 1
Citation - Scopus: 1
A Novel Approach Utilizing Rapid Thin-Film Microextraction Method for Salivary Metabolomics Studies in Lung Cancer Diagnosis
(Elsevier, 2024) Pelit, Fusun; Erbas, Ilknur; Ozupek, Nazli Mert; Gul, Merve; Sakrak, Esra; Ocakoglu, Kasim; Goksel, Ozlem; Özdemir, Durmuş
This study investigated the potential of targeted salivary metabolomics as a convenient diagnostic tool for lung cancer (LC), utilizing a rapid TFME-based method. It specifically examines TFME blades modified with SiO2 nanoparticles, which were produced using a custom-made coating system. Validation of the metabolite biomarker analysis was performed by these blades using liquid chromatography-tandem mass spectroscopy (LCMS/MS). The extraction efficiencies of SiO2 nanoparticle/polyacrylonitrile (PAN) composite-coated blades were compared for 18 metabolites. Response surface methodology (RSM) was used to optimize the analysis conditions. Linear calibration plots were obtained for all metabolites at concentrations between 0.025 to 4.0 mu g/mL in the presence of internal standard, with correlation coefficients (R-2) ranging from 0.9975 to 0.9841. The limit of detection (LOD) and limit of quantitation (LOQ) were in the range of 0.014 to 0.97 mu g mL(-1) and 0.046 to 3.20 mu gmL(-1), respectively. The %RSD values for all analytes were within the acceptable range (less than 20 %) for the proposed method. The method was applied to the saliva samples of 40 patients with LC and 38 healthy controls. The efficacy of metabolites for LC diagnosis was determined by in silico methods and the results reveal that phenylalanine and purine metabolism metabolites (e.g., hypoxanthine) are of great importance for LC diagnosis. Furthermore, potentially significant biomarker analysis results from the ROC curve data reveal that proline, hypoxanthine, and phenylalanine were identified as potential biomarkers for LC diagnosis.
Citation - Scopus: 3
Advances and Future Perspective of Graphene Field Effect Transistors (gfets) for Medical Diagnostics and Point-Of Tools
(World Scientific Publishing, 2022) İnanç, Dilce; Mutlu, Mustafa Umut; Karabacak, Soner; Yıldız, Ümit Hakan
Recently, major focus has been centered to enhance the capability of graphenebased devices and to facilitate utilization of graphene for biological applications by lowering its toxicity. In this chapter, from synthesis to applications, many of the conspicuous characteristics of graphene have been elaborately reviewed. We primarily focused on graphene-based field effect transistor (FET) for medical diagnostics and point-of-care applications. The device configurations and their application potential as well as sensing capability of various graphene FETs (GFETs) have been discussed. Here, we have also presented several aspects and advantages of GFETs in medical applications while discussing their pros and cons in commercialization. We address the advances and challenges for GFET-based sensing platforms for the medical applications and elaborate the combination strategy of GFETs with the existing commercial systems. © 2023 by World Scientific Publishing Co. Pte. Ltd.
Citation - WoS: 3
Citation - Scopus: 4
1,2-Diboranes With Strong Donor Substitutes: Synthesis, Ovicidal and Larvicidal Effect on Important Vector Species
(Elsevier, 2024) Bursali, Fatma; Sahin, Yueksel; Aygun, Muhittin; Sevincek, Resul; Biyik, H. Halil; Özgener, Hüseyin; Gurbuz, Burcin
Novel control products are needed in the control of important insects like mosquitoes which are developing resistance to insecticides and larvicides currently in the market. Boron compounds have been demonstrated to exhibit antibacterial and anticancer effects. 1,2-diboranes with a long history and importance in boron chemistry have been described. These compounds are synthesized from reactions of 1,2-dichlordiborane derivatives with lidium amides (ArNHLi/Et2NLi, etc.). In addition to the three previously synthesized diborane compounds, five novel 1,2-diborane compounds were synthesized in good yield using the same method for the first time. The structures of the novel derivatives were characterized by nuclear magnetic resonance spectroscopy, and the molecular structure of one of them (2a) was also demonstrated using single crystal X-ray diffraction. In this preliminary study, the ovicidal and larvicidal effects of new 1,2-diamino-1,2-diborane derivatives against Aedes aegypti and Aedes albopictus eggs and larvae were investigated for the first time. Of these, 2a and 2e showed the highest ovicidal activity against both species, while 7, 4 and 2d showed particularly high larvicidal activity. Some 1,2-diborane derivatives were found to be significantly toxic, with LC50 values ranging from 14,930 to 27,975 mu g/mL. Some derivatives (6, 2a, 2c) were less effective against mosquito larvae. 1,2-Diborane derivatives have high ovicidal and larvicidal effects on mosquitoes and are therefore potential candidates for the development of new larvicides. Further studies are needed to evaluate its mode of action and safety. Understanding their mode of action against mosquito development is crucial to optimizing their use and reducing the potential development of resistance. Their potential effects on other mosquito species and non -target organisms need to be investigated.
Citation - Scopus: 3
Development of Chrono-Spectral Gold Nanoparticle Growth Based Plasmonic Biosensor Platform
(Elsevier, 2024) Sözmen, Alper Baran; Elveren, Beste; Erdoğan, Duygu; Mezgil, Bahadır; Baştanlar, Yalın; Yıldız, Ümit Hakan; Arslan Yıldız, Ahu
Plasmonic sensor platforms are designed for rapid, label-free, and real-time detection and they excel as the next generation biosensors. However, current methods such as Surface Plasmon Resonance require expertise and well-equipped laboratory facilities. Simpler methods such as Localized Surface Plasmon Resonance (LSPR) overcome those limitations, though they lack sensitivity. Hence, sensitivity enhancement plays a crucial role in the future of plasmonic sensor platforms. Herein, a refractive index (RI) sensitivity enhancement methodology is reported utilizing growth of gold nanoparticles (GNPs) on solid support and it is backed up with artificial neural network (ANN) analysis. Sensor platform fabrication was initiated with GNP immobilization onto solid support; immobilized GNPs were then used as seeds for chrono-spectral growth, which was carried out using NH2OH at varied incubation times. The response to RI change of the platform was investigated with varied concentrations of sucrose and ethanol. The detection of bacteria E.coli BL21 was carried out for validation as a model microorganism and results showed that detection was possible at 102 CFU/ml. The data acquired by spectrophotometric measurements were analyzed by ANN and bacteria classification with percentage error rates near 0% was achieved. The proposed LSPR-based, label-free sensor application proved that the developed methodology promises utile sensitivity enhancement potential for similar sensor platforms. © 2024 The Author(s)
Citation - WoS: 6
Citation - Scopus: 6
A Novel 2-Aminophenalenone Fluorescent Probe Designed for Monitoring H2o2 for in Vitro and in Vivo Bioimaging
(Elsevier, 2024) Saygılı, Ecem; Ersöz Gülseven, Esra; Kıbrıs, Erman; Çakan Akdoğan, Gülçin; Üçüncü, Muhammed
A significant compound in living organisms, hydrogen peroxide (H2O2) plays a dual role as a signalling molecule in cellular communication and as a pivotal biomarker in assessing disease and oxidative stress. Thus, the detection of abnormal changes in H2O2 levels is essential to understanding its function and involvement in biological systems. The growing demand to meet the specific needs for applications, particularly in biological systems, has sharpened focus on highly sensitive, highly selective molecular sensors and, in turn, heightened interest in these diagnostic tools with innovative designs. In our study, 2-aminophenalenone (2-AP) was used for the first time as a fluorophore in a fluorescent probe. The 2-APB molecule obtained from the reaction of 2-AP with 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) benzyl chloroformate exhibited a highly selective and sensitive (i.e. 62 nM) detection profile for H2O2 compared with the other reactive oxygen species, anions, and metal cations. Moreover, offering naked-eye detection in aqueous solutions, 2-APB demonstrated excellent sensing performance, detection and real-time monitoring in relation to exogenous H2O2 in cells and endogenous H2O2 in zebrafish embryos. © 2024 Elsevier B.V.
Free-Standing Three-Dimensional Graphene Scaffolds for Protease Functional Assay
(Elsevier Science Sa, 2024) Ng, Zhi Kai; Yan, Evelias; Goyal, Garima; Gudlur, Sushanth; Kanagavel, Deepankumar; Yildiz, Umit Hakan; Teo, Edwin Hang Tong
Three-dimensional graphene scaffolds (3d-GS) of high porosity possessing good fluorescence quenching properties are potential candidates for the development of optical biosensors. Herein, we demonstrate the feasibility of utilising intact and free-standing 3d-GS for sensitive detection of proteases, a class of disease diagnosis bio-markers of significant interest. Recombinant OmpT was employed as a model protease for validating the pro-posed methodology. A short (15-residue) peptide sequence encoding a specific recognition site for OmpT was end-labelled with a fluorescent dye (5-FAM) whose fluorescence is quenched when the peptide is anchored to 3d-GS. However, in the presence of OmpT, the peptide is cleaved and released from 3d-GS, resulting in a sig-nificant recovery in fluorescence. The functional assay described herein involves a single step fabrication process of anchoring the peptide to 3d-GS. The integrity of the 3d-GS is hypothesised to overcome the concern of dynamic requenching associated with the typical homogeneous assays based on graphene, yielding a limit of detection (LOD) of similar to 140 nM, which is over an order higher than homogeneous assays performed using the same composition of graphene in powdered form. To the best of our knowledge, this is the first report on utilising free-standing 3d-GS for facile assaying of proteases.
Citation - WoS: 1
Citation - Scopus: 1
The Soft Nanodots as Fluorescent Probes for Cell Imaging: Analysis of Cell and Spheroid Penetration Behavior of Single Chain Polymer Dots
(Wiley, 2024) Yücel, Müge; Onbaş, Rabia; Arslan Yıldız, Ahu; Yıldız, Ümit Hakan
This study describes the formation, size control, and penetration behavior of polymer nanodots (Pdots) consisting of single or few chain polythiophene-based conjugated polyelectrolytes (CPEs) via nanophase separation between good solvent and poor solvent of CPE. Though the chain singularity may be associated with dilution nanophase separation suggests that molecules of a good solvent create a thermodynamically driven solvation layer surrounding the CPEs and thereby separating the single chains even in their poor solvents. This statement is therefore corroborated with emission intensity/lifetime, particle size, and scattering intensity of polyelectrolyte in good and poor solvents. Regarding the augmented features, Pdots are implemented into cell imaging studies to understand the nuclear penetration and to differentiate the invasive characteristics of breast cancer cells. The python based red, green, blue (RGB) color analysis depicts that Pdots have more nuclear penetration ability in triple negative breast cancer cells due to the different nuclear morphology in shape and composition and Pdots have penetrated cell membrane as well as extracellular matrix in spheroid models. The current Pdot protocol and its utilization in cancer cell imaging are holding great promise for gene/drug delivery to target cancer cells by explicitly achieving the very first priority of nuclear intake. The penetration capability of cationic soft nanodots in to tumor models of breast cancer is demonstrated. The image analysis based on fluorescence intensity variation reveals the characteristics of translocation of nanodots in dense mediums such as tumor models.image
Citation - WoS: 2
Citation - Scopus: 2
Roadmap on Multifunctional Materials for Drug Delivery
(IOP Publishing, 2024) Nottelet, Benjamin; Buwalda, Sytze; van Nostrum, Cornelus F.; Zhao, Xiaofei; Deng, Chao; Zhong, Zhiyuan; Cheah, Ernest; Kehr, Nermin Seda
This Roadmap on drug delivery aims to cover some of the most recent advances in the field of materials for drug delivery systems (DDSs) and emphasizes the role that multifunctional materials play in advancing the performance of modern DDSs in the context of the most current challenges presented. The Roadmap is comprised of multiple sections, each of which introduces the status of the field, the current and future challenges faced, and a perspective of the required advances necessary for biomaterial science to tackle these challenges. It is our hope that this collective vision will contribute to the initiation of conversation and collaboration across all areas of multifunctional materials for DDSs. We stress that this article is not meant to be a fully comprehensive review but rather an up-to-date snapshot of different areas of research, with a minimal number of references that focus upon the very latest research developments.
Citation - WoS: 7
Citation - Scopus: 10
Design, Fabrication, and Application of Micro-Structured Surfaces for Laser-Induced Breakdown Spectroscopic Analysis of Liquids: a Sample-Loading Target Development Studies
(Elsevier, 2024) Kaplan, Dilara; Aras, Nadir; Yalcin, Serife
In this paper, design, fabrication, and application studies of a sample loading target patterned with periodical micro-structures were presented. Two different geometrical shapes; triangular prisms and cylinders of two different feature sizes; 5-mu m, and 20-mu m, were photo-lithographically patterned on Si-wafer substrates, and dry etched to 10 mu m height. Followed by a 1-mu m thick silicon nitride film coating over micro-patterned substrates, final products were obtained after dicing into one-inch size squares, each containing 36 patterned sample loading areas. Among the three different patterns studied; a geometric design with 20-mu m diameter cylinders exhibited a more effective task in increasing the LIBS signal strength, compared to the other two patterns. The characterization of the surface morphology and the size-shape distribution of the micro-patterns were carried out through optical and scanning electron microscopic measurements. SEM images proved a more effective ablation occur-ring on triangular prism micro-structured surfaces that can be associated with an increased path length and enhanced absorption of the laser beam on the flat surfaces of triangular prism via multiple reflections. The results of structured surfaces were also compared with the ones from non-structured surfaces of 300 nm and 1000 nm thicknesses of silicon nitride-coating. The applications of micro-structured surfaces for heavy metals analysis were performed with Cr and Pb solutions via dried-droplet LIBS methodology. The enhancement factor of 4 for Pb(I) 405.8 nm, and 8 for Cr(I) 428.9 nm were observed from the 20-mu m diameter cylinder, CYL-20, surfaces compared to 300 nm thick Si3N4 surfaces, respectively. This study of micro-structuring substrate surfaces with an emphasis on the signal enhancement effect is promising in terms of improving the capacity and limitations of the dried-droplet methodology by LIBS.
Citation - Scopus: 1
A Perspective on the State-Of Functionalized 2d Materials
(American Institute of Physics, 2023) Duran, Tuna; Yayak, Yankı Öncü; Aydın, Hasan; Peeters, François M.; Yağmurcukardeş, Mehmet
Two-dimensional (2D) ultra-thin materials are more crucial than their bulk counterparts for the covalent functionalization of their surface owing to atomic thinness, large surface-to-volume ratio, and high reactivity of surface atoms having unoccupied orbitals. Since the surface of a 2D material is composed of atoms having unoccupied orbitals, covalent functionalization enables one to improve or precisely modify the properties of the ultra-thin materials. Chemical functionalization of 2D materials not only modifies their intrinsic properties but also makes them adapted for nanotechnology applications. Such engineered materials have been used in many different applications with their improved properties. In the present Perspective, we begin with a brief history of functionalization followed by the introduction of functionalized 2D materials. Our Perspective is composed of the following sections: the applications areas of 2D graphene and graphene oxide crystals, transition metal dichalcogenides, and in-plane anisotropic black phosphorus, all of which have been widely used in different nanotechnology applications. Finally, our Perspectives on the future directions of applications of functionalized 2D materials are given. The present Perspective sheds light on the current progress in nanotechnological applications of engineered 2D materials through surface functionalization. © 2023 Author(s).
Citation - WoS: 17
Citation - Scopus: 15
Antiproliferative and Apoptotic Effects of Olive Leaf Extract Microcapsules on Mcf-7 and A549 Cancer Cells
(American Chemical Society, 2023) Bal, Yıldız; Sürmeli, Yusuf; Şanlı Mohamed, Gülşah
Alginate microcapsules are a talented means for the delivery of broad curative biomacromolecules. In this study, we immobilized olive leaf extract (OLE) by calcium alginate (CA) and chitosan-coated CA (CCA) and characterized the OLE-loaded CA and CCA. The cytotoxic effect, the cell cycle arrest, and the apoptotic effect of OLE and its microcapsules were investigated against breast adenocarcinoma (MCF-7) and lung carcinoma (A549). As a result, the loading capacity of OLE-CA and OLE-CCA was found to be 80 and 99%, respectively, in optimal conditions. Also, OLE-CA and OLE-CCA were characterized by unique FTIR peaks and morphological display relative to the empty CCA microcapsules. The cytotoxicity analysis showed that the IC50 values of OLE-CA and OLE-CCA were determined to be 312 and 0.94 μg mL-1 against A549, respectively, whereas these were found to be 865.4 and 425.5 μg mL-1 for MCF-7 cells. On the other hand, the OLE microcapsules did not possess in any concentration of cytotoxic influence on the BEAS 2B healthy cell line. Also, the exposure of OLE-CCA to MCF-7 and A549 resulted in the arrest of more MCF-7 and A549 cells at the G0/G1 phase compared to the OLE. A549 and MCF-7 cells were predominantly found in the late apoptosis phase and necrosis phase, respectively. Optical microscopy images confirmed that OLE microcapsules were more effective against MCF-7 and A549 than free OLE. The present work suggested that the OLE microcapsules might be administered as nutrition supplements for cancer therapy. © 2023 The Authors. Published by American Chemical Society.
Citation - WoS: 1
Citation - Scopus: 2
A Phenomenological Kinetic Flotation Model: Distinct Time-Variant Floatability Distributions for the Pulp and Froth Materials
(Elsevier, 2023) Polat, Mehmet; Polat, Hürriyet
A simple and easy-to-use phenomenological kinetic flotation model, strongly connected with the physics of the process, is proposed in this paper. The model explicitly contains the cell volume, aeration rate, volumetric holdup, mean bubble size, and particle density as input variables. It can be employed to characterize the floatability distributions of the particles in the pulp and the froth separately any time during the flotation process. Two new time-dependent kinetic parameters, the bubble loading factor & phi;(t) and the maximum cell mass transfer capacity Mmax(t) also appear in the model expression. & phi;(t) is a measure of the degree of crowding of the bubble surfaces and accounts for the deviations from the first-order rate equation. Mmax(t) describes the maximum amount of mass that can be transported to the froth phase by the bubble population in the cell. Screen fractionation of each froth product collected at different time intervals during a single kinetic flotation test is sufficient to generate the data required by the model for analysis. Application of the model to this data yields directly time-dependent functions for the floatability of the particles reporting to froth Kf(t) or remaining in the cell Kp(t) for each size fraction separately, without the need for any empirical parameters. The test of the model was carried out using published kinetic flotation data from the literature.
Citation - WoS: 2
Citation - Scopus: 2
Gas Phase Fragmentation Behavior of Proline in Macrocyclic B7 Ions
(American Chemical Society, 2023) Taşoğlu, Çağdaş; Arslanoğlu, Alper; Yalçın, Talat
Thefragmentation characteristics of b (7) ionsproduced from proline-containing heptapeptides have been studiedin detail. The study has utilized the following C-terminally amidatedmodel peptides: PA(6), APA(5), A(2)PA(4), A(3)PA(3), A(4)PA(2), A(5)PA, A(6)P, PYAGFLV, PAGFLVY, PGFLVYA, PFLVYAG,PLVYAGF, PVYAGFL, YPAGFLV, YAPGFLV, YAGPFLV, YAGFPLV, YAGFLPV, YAGFLVP,PYAFLVG, PVLFYAG, A(2)PXA(3), and A(2)XPA(3) (where X = C, D, F, G, L, V, and Y, respectively). The resultshave shown that b (7) ions undergo head-to-tailcyclization and form a macrocyclic structure. Under the collision-induceddissociation (CID) condition, it generates nondirect sequence ionsregardless of the position of the proline and the neighboring aminoacid residues. This study highlights the unusual and unique fragmentationbehavior of proline-containing heptapeptides. Following the head-to-tailcyclization, the ring opens up and places the proline residue in theN-terminal position while forming a regular oxazolone form of b (2) ions for all peptide series. Then, the fragmentationreaction pathway is followed by the elimination of proline with itsC-terminal neighbor residue as an oxazolone (e.g., PXoxa) for all proline-containing peptide series.
Citation - WoS: 1
Citation - Scopus: 1
Investigation of Cytotoxic Properties of Some Isoindole-Related Compounds Bearing Silyl and Azide Groups With in Vitro and in Silico Studies
(Taylor & Francis, 2023) Tan, Ayşe; Köse, Aytekin; Mete, Derya; Şanlı Mohamed, Gülşah; Kışhalı, Nurhan H.; Kara, Yunus
This study aims to evaluate the synthesis of isoindole-1,3-dione analogues and their cytotoxic potential. A549 and HeLa cells exposed to 250-100-50-25 mu M doses of each derivative were incubated for 24, 48, and 72 h. The cytotoxicity of the isoindole-1,3-dione derivatives was analyzed using the cell growth inhibition assay and the cell membrane damage test. (3aR,5R,6R,7aS)-5-Azido-2-benzyl-6-hydroxyhexahydro-1H-isoindole-1,3(2H)-dione (1d), (3aR,5R,6R,7aS)-5-azido-6-((tert-butyldiphenylsilyl)oxy)-2-ethylhexahydro-1H-isoindole-1,3(2H)-dione (2a), and (3aR,5R,6R,7aS)-5-azido-6-((tert-butyldiphenylsilyl)oxy)-2-methylhexahydro-1H-isoindole-1,3(2H)-dione (2b) compounds inhibited the growth of the A549 and HeLa cells caused membrane damage and exhibited a dose-dependent cytotoxic effect on lung and cervical carcinoma cells. The effect of tert-butyldiphenylsilyl (TBDPS) groups on cytotoxicity was observed in compounds 2a and 2b, but not in the other compounds. Considering the effect of groups attached to the nitrogen atom, the best activity was exhibited in 2b molecule to which the methyl group is attached. Additionally, the interactions of compounds (3aR,5R,6R,7aS)-5-azido-6-hydroxy-2-methylhexahydro-1H-isoindole-1,3(2H)-dione (1b), 1d, 2a and 2b with mammalian rapamycin target, human ribosomal S6 kinase 1 and human epidermal growth factor receptor were investigated by molecular docking studies, . According to the docking results, 2a and 2b compounds containing a TBDPS group have stronger binding energies than 1b and 1d compounds against all target receptors.
Citation - WoS: 2
Citation - Scopus: 5
Immobilization of Olive Leaf Extract With Chitosan Nanoparticles as an Adjunct To Enhance Cytotoxicity
(American Chemical Society, 2023) Özdamar, Burcu; Sürmeli, Yusuf; Şanlı Mohamed, Gülşah
We immobilized the olive leaf extract (OLE) with chitosannanoparticles(CNPs) by optimizing the effect of various immobilization conditions,and OLE-loaded CNPs (OLE-CNPs) were then elaborately characterizedphysicochemically by scanning electron microscopy (SEM), Fourier transforminfrared (FT-IR) spectroscopy, dynamic light scattering (DLS), andatomic force microscopy (AFM). Under optimal conditions, CNPs wereable to accommodate the OLE with a loading capacity of 97.5%. Theresulting OLE-CNPs had a spherical morphology, and their average diameterwas approximately 100 nm. The cytotoxic influence, cell cycle distribution,and apoptosis stage of OLE and OLE-CNPs were analyzed on lung carcinoma(A549) and breast adenocarcinoma (MCF-7) cell lines. In an in vitrocytotoxic assay, IC50 values of OLE-CNPs were determinedto be 540 & mu;g/mL for A549 and 810 & mu;g/mL for MCF-7. Thetreatment of both A549 and MCF-7 with OLE-CNPs caused the highestcell arrest in G0/G1 in a dose-independent manner. OLE-CNPs affectedcell cycle distribution in a manner different from free OLE treatmentin both cancer cells. A549 and MCF-7 cells were predominantly foundin the late apoptosis and necrosis phases, respectively, upon treatmentof 1000 & mu;M OLE-CNPs. Our results suggest that CNPs enhance theutility of OLEs as nutraceuticals in cancer and that OLE-CNPs canbe utilized as an adjunct to cancer therapy.
Citation - WoS: 3
Citation - Scopus: 3
Halloysite Nanotube Loaded Polyamide Nanocomposites: Structural, Morphological, Mechanical, Thermal and Processing Behaviors
(American Institute of Physics, 2023) Akar, Alinda Öykü; Yıldız, Ümit Hakan; Tayfun, Ümit
In this study, the polyamide 6 (PA) matrix was reinforced with the purified, fine ground and amino-silane treated halloysite nanotubes (HNT) at different concentrations. The preparation of composites was carried out using a lab-scale twin-screw micro-compounder with loading ratios at 0.5, 1, 3, and 20% by weight, and the test samples were prepared by the injection-molding process. According to mechanical test results, additions of HNT to the PA matrix caused slight improvements in tensile strength and Youngs' modulus parameters. The optimum concentrations for all of the additives used were estimated by comparison of mechanical test data. The addition of aminosilane-modified HNT resulted in a higher impact performance at high loading levels up to 3% concentrations. Further addition of HNT caused a reduction in the mechanical parameters of composites. Thermal studies revealed that the glass transition temperature of PA shifted to higher values after HNT mineral inclusions. Thermo-mechanical results showed that storage moduli of PA exhibited improvement with an increase in HNT content. The distributions of HNT clay into the PA phase were visualized with SEM images. Based on these observations, a high level of dispersion homogeneity was achieved for lower filling ratios. According to melt-flow and force measurements, composites filled with 20% of HNT displayed a remarkable increase in exerted force during melt-blending. © 2023 Author(s).
Citation - WoS: 4
Citation - Scopus: 4
Polarity Induced Vapochromism and Vapoluminescence of Polythiophene Derivatives for Volatile Organic Compounds Classification
(Elsevier, 2023) Karabacak, Soner; Qun, David Lee Chao; Ammanath, Gopal; Yeasmin, Sanjida; Yağmurcukardeş, Mehmet; Palaniappan, Alagappan; Liedberg, Bo; Yıldız, Ümit Hakan
Polarity induced vapochromic and vapoluminescent properties of cationic poly-3-alkoxythiophene derivatives (PT) casted on polyvinylidene fluoride (PVDF) membranes are reported. PT with six different pendant groups are designed to differentially interact with volatile organic compounds (VOC) of varying polarities, thereby enabling their classification. PT exhibit a rapid vapochromic response with a concurrent modulation of vapoluminescence due to the non-covalent cation-? interactions between the pendant groups and the PT backbone. Adsorption of VOC on pendant groups alters the conformation of PT backbone, thus resulting in an increase in intensity and blue shifting of fluorescence emission within the visible spectrum. The vapoluminescent responses are found to be more sensitive with a limit of detection (LOD) of ?7 ppm and a wider dynamic range as compared to the vapochromic responses with a LOD of ?60 ppm for the detection of a model VOC: chloroform. Notably, all the PT illustrate an instantaneous recovery of colour and luminescence upon desorption of VOC. PT interaction with VOC of varying polarities was ascertained using density functional theory (DFT) and principal component analysis (PCA) methodologies. In summary, the polarity induced vapochromic and vapoluminescent properties of PT could yield a selective and sensitive vapochromic and fluorometric dual-mode VOC detection platform. © 2023
Citation - Scopus: 3
Tissue Engineering Applications of Marine-Based Materials
(Springer, 2022) Polat, Hürriyet; Zeybek, Nuket; Polat, Mehmet
Tissue engineering is a promising approach in replacing or improving tissues lost or has become nonviable due to disease or trauma by the use of scaffold materials by combining engineering and biochemical/physicochemical methods. Its purpose is to create suitable matrices that support cell differentiation and proliferation toward the formation of new and functional tissue. Marine-based natural compounds are potential scaffold feedstock material in tissue engineering owing to their biocompatibility and biodegradability while providing excellent biochemical/physicochemical properties. Numerous application areas and various fabrication routes techniques described in the literature attest to the importance of these materials in tissue regeneration. This review has been carried to merge the information from a large number of studies on the marine-based scaffold materials in tissue engineering into a coherent summary. © The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2022.
Citation - WoS: 1
Citation - Scopus: 1
Editorial: Biomaterial Applications in Soft Tissue Engineering and Replacement
(Frontiers Media S.A., 2023) Hornyak, Istvan; Jedlovszky-Hajdu, Angela; Kehr, Seda
The research related to the application of biomaterials encompasses a large area within the field of tissue engineering and regenerative medicine (TERM), and this Research Topic was dedicated to the versatile possibilities in the use of biomaterials. The sum of 10 manuscripts were submitted to this Research Topic and six were selected for this Research Topic with the contribution of 35 authors, Four of the accepted manuscripts were original research articles and two were review articles
Citation - WoS: 91
Citation - Scopus: 93
Salivary Biomarkers: Novel Noninvasive Tools To Diagnose Chronic Inflammation
(Springer, 2023) Dongiovanni, Paola; Meroni, Marica; Casati, Sara; Goldoni, Riccardo; Thomaz, Douglas Vieira; Kehr, Nermin Seda; Galimberti, Daniela
Several chronic disorders including type 2 diabetes (T2D), obesity, heart disease and cancer are preceded by a state of chronic low-grade inflammation. Biomarkers for the early assessment of chronic disorders encompass acute phase proteins (APP), cytokines and chemokines, pro-inflammatory enzymes, lipids and oxidative stress mediators. These substances enter saliva through the blood flow and, in some cases, there is a close relation between their salivary and serum concentration. Saliva can be easily collected and stored with non-invasive and cost-saving procedures, and it is emerging the concept to use it for the detection of inflammatory biomarkers. To this purpose, the present review aims to discuss the advantages and challenges of using standard and cutting-edge techniques to discover salivary biomarkers which may be used in diagnosis/therapy of several chronic diseases with inflammatory consequences with the pursuit to possibly replace conventional paths with detectable soluble mediators in saliva. Specifically, the review describes the procedures used for saliva collection, the standard approaches for the measurement of salivary biomarkers and the novel methodological strategies such as biosensors to improve the quality of care for chronically affected patients.

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