WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Iron Oxide Nanocube Assembly on Silver Nanowire Templates to Enhance Magnetic Hyperthermia Performance(Royal Society of Chemistry, 2026) Balcı, Sinan; Tiryaki, Ecem; Sadeghi, Ehsan; Mannir, Abubakar R.; Balci, Sinan; Pellegrino, Teresa; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyIron oxide nanocubes (IONCs) represent one of the benchmark magnetic nanoparticles able to most efficiently convert magnetic energy into heat for magnetic hyperthermia cancer treatment, and their heat losses can be further increased by controlling their assembly through the synthesis of ordered structures. However, achieving the alignment of nanoparticles with one-dimensional chain or columnar structures into long arrays to then study their magnetic heat losses still remains a significant challenge. This study exploits silver nanowires as high-surface-area anisotropic templates for the controlled chaining of IONCs. The surfaces of the IONCs were purposely functionalized with polyethyleneimine (IONCs@PEI) and interacted with silver nanowire (AgNW) surfaces via electrostatic attraction. Here, alternating current (AC) magnetometry was employed to compare the heating performance expressed as specific absorption rate values between individually coated IONCs@PEI and AgNWs@IONCs@PEI composites at various magnetic field strengths and frequencies. SAR values reveal that clustering of IONCs on AgNW surfaces improves the heating efficiency at an applied magnetic field strength of 24 kA m-1, regardless of the applied frequencies, with SAR values of AgNWs@IONCs@PEI composites outperforming those of individual IONCs@PEI. Moreover, dynamic hysteresis loops showed that the coercive field of AgNWs@IONCs@PEI increased significantly at 24 kA m-1, indicating the existence of strong magnetic dipolar interactions between nanoparticles. This study shows an innovative approach for guiding the orientation of magnetic nanoparticles using one-dimensional templates to enhance their heating performance.Review Citation - WoS: 14Citation - Scopus: 14Recent Advances in Lab-On Systems for Breast Cancer Metastasis Research(Royal Society of Chemistry, 2023) Fıratlıgil Yıldırır, Burcu; Fıratlıgil Yıldırır, Burcu; Yalçın Özuysal, Özden; 04.03. Department of Molecular Biology and Genetics; 04. Faculty of Science; 01. Izmir Institute of TechnologyBreast cancer is the leading cause of cancer-related deaths in women. Multiple molecular subtypes, heterogeneity, and their ability to metastasize from the primary site to distant organs make breast cancer challenging to diagnose, treat, and obtain the desired therapeutic outcome. As the clinical importance of metastasis is dramatically increasing, there is a need to develop sustainable in vitro preclinical platforms to investigate complex cellular processes. Traditional in vitro and in vivo models cannot mimic the highly complex and multistep process of metastasis. Rapid progress in micro- and nanofabrication has contributed to soft lithography or three-dimensional printing-based lab-on-a-chip (LOC) systems. LOC platforms, which mimic in vivo conditions, offer a more profound understanding of cellular events and allow novel preclinical models for personalized treatments. Their low cost, scalability, and efficiency have resulted in on-demand design platforms for cell, tissue, and organ-on-a-chip platforms. Such models can overcome the limitations of two- and three-dimensional cell culture models and the ethical challenges involved in animal models. This review provides an overview of breast cancer subtypes, various steps and factors involved in metastases, existing preclinical models, and representative examples of LOC systems used to study and understand breast cancer metastasis and diagnosis and as a platform to evaluate advanced nanomedicine for breast cancer metastasis.Article Citation - WoS: 13Citation - Scopus: 14Synthesizing and Evaluating the Photodynamic Efficacy of Asymmetric Heteroleptic A(7)b Type Novel Lanthanide Bis-Phthalocyanine Complexes(Royal Society of Chemistry, 2021) Önal, Emel; Tüncel, Özge; Özçelik, Serdar; Tüncel, Özge; Gül Gürek, Ayşe; Özçelik, Serdar; 04.03. Department of Molecular Biology and Genetics; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyIn this study heteroleptic A(7)B type novel Lu(iii) and Eu(iii) lanthanide phthalocyanines (LnPc(Pox)[Pc '(AB(3)SH)]) with high extinction coefficients have been synthesized as candidate photosensitizers with reaction yields higher than 33%. The singlet oxygen quantum yields of LuPc(Pox)[Pc '(AB(3)SH)] and EuPc(Pox)[Pc '(AB(3)SH)], respectively, were measured 17% and 1.4% by the direct method in THF. The singlet oxygen quantum yield of LuPc(Pox)[Pc '(AB(3)SH)] in THF is the highest among lutetium(iii) bis-phthalocyanine complexes to date. The photodynamic efficacy of the heteroleptic lanthanide phthalocyanines was evaluated by measuring cell viabilities of A549 and BEAS-2B lung cells, selected to representing in vitro models for testing cancer and normal cells against potential drugs. The cell viabilities demonstrated concentration dependent behavior and were varied by the type of phthalocyanines complexes. Irradiation of the cells for 30 minutes with LED array at 660 nm producing flux of 0.036 J cm(-2) s(-1) increased cell death for LuPcPox-OAc, LuPc(Pox)[Pc '(AB(3)SH)] and ZnPc. The IC50 concentrations of LuPc(Pox)[Pc '(AB(3)SH)] and ZnPc were determined to be below 10 nM for both cell lines, agreeing very well with the singlet oxygen quantum yield measurements. These findings suggest that LuPc(Pox)[Pc '(AB(3)SH)] and particularly LuPcPox-OAc are promising drug candidates enabling lowered dose and shorter irradiation time for photodynamic therapy.Article Citation - WoS: 10Citation - Scopus: 10Vibrational and Optical Identification of Geo2 and Geo Single Layers: a First-Principles Study(Royal Society of Chemistry, 2021) Sözen, Yiğit; Yağmurcukardeş, Mehmet; Şahin, Hasan; 04.04. Department of Photonics; 01. Izmir Institute of Technology; 04. Faculty of ScienceIn the present work, the identification of two hexagonal phases of germanium oxides (namely GeO2 and GeO) through the vibrational and optical properties is reported using density functional theory calculations. While structural optimizations show that single-layer GeO2 and GeO crystallize in 1T and buckled phases, phonon band dispersions reveal the dynamical stability of each structure. First-order off-resonant Raman spectral predictions demonstrate that each free-standing single-layer possesses characteristic peaks that are representative for the identification of the germanium oxide phase. On the other hand, electronic band dispersion analysis shows the insulating and large-gap semiconducting nature of single-layer GeO2 and GeO, respectively. Moreover, optical absorption, reflectance, and transmittance spectra obtained by means of G(0)W(0)-BSE calculations reveal the existence of tightly bound excitons in each phase, displaying strong optical absorption. Furthermore, the excitonic gaps are found to be at deep UV and visible portions of the spectrum, for GeO2 and GeO crystals, with energies of 6.24 and 3.10 eV, respectively. In addition, at the prominent excitonic resonances, single-layers display high reflectivity with a zero transmittance, which is another indication of the strong light-matter interaction inside the crystal medium.Article Citation - WoS: 23Citation - Scopus: 23Bodipy-Vinyl Dibromides as Triplet Sensitisers for Photodynamic Therapy and Triplet-Triplet Annihilation Upconversion(Royal Society of Chemistry, 2021) Dartar, Suay; Emrullahoğlu, Mustafa; Karakuş, Erman; Hou, Yuqi; Zhao, Jianzhang; Emrullahoğlu, Mustafa; 04.01. Department of Chemistry; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe devised a new generation of halogen-based triplet sensitisers comprising geminal dibromides at the vinyl backbone of a BODIPY fluorophore. Incorporating geminal dibromides into the pi-conjugation of BODIPY enhanced intersystem crossing due to the heavy atom effect, which in turn improved the extent of excited triplet states.Article Citation - WoS: 34Citation - Scopus: 34Decellularised Extracellular Matrix Decorated Pcl Polyhipe Scaffolds for Enhanced Cellular Activity, Integration and Angiogenesis(Royal Society of Chemistry, 2021) Dikici, Serkan; Aldemir Dikici, Betül; Dikici, Serkan; Aldemir Dikici, Betül; 03.01. Department of Bioengineering; 03. Faculty of Engineering; 01. Izmir Institute of TechnologyWound healing involves a complex series of events where cell-cell and cell-extracellular matrix (ECM) interactions play a key role. Wounding can be simple, such as the loss of the epithelial integrity, or deeper and more complex, reaching to subcutaneous tissues, including blood vessels, muscles and nerves. Rapid neovascularisation of the wounded area is crucial for wound healing as it has a key role in supplying oxygen and nutrients during the highly demanding proliferative phase and transmigration of inflammatory cells to the wound area. One approach to circumvent delayed neovascularisation is the exogenous use of pro-angiogenic factors, which is expensive, highly dose-dependent, and the delivery of them requires a very well-controlled system to avoid leaky, highly permeable and haemorrhagic blood vessel formation. In this study, we decorated polycaprolactone (PCL)-based polymerised high internal phase emulsion (PolyHIPE) scaffolds with fibroblast-derived ECM to assess fibroblast, endothelial cell and keratinocyte activity in vitro and angiogenesis in ex ovo chick chorioallantoic membrane (CAM) assays. Our results showed that the inclusion of ECM in the scaffolds increased the metabolic activity of three types of cells that play a key role in wound healing and stimulated angiogenesis in ex ovo CAM assays over 7 days. Herein, we demonstrated that fibroblast-ECM functionalised PCL PolyHIPE scaffolds appear to have great potential to be used as an active wound dressing to promote angiogenesis and wound healing.Article Citation - WoS: 4Citation - Scopus: 6An Anticounterfeiting Technology Combining an Inp Nanoparticle Ink and a Versatile Optical Device for Authentication(Royal Society of Chemistry, 2021) Özçelik, Serdar; Taşcıoğlu, Didem; Özçelik, Serdar; 04.01. Department of Chemistry; 01. Izmir Institute of Technology; 04. Faculty of ScienceCounterfeiting is a growing issue and causes economic losses. Fluorescent inks containing In(Zn)P/ZnS/DDT colloidal nanoparticles are formulated and combined with a convenient optical device for authentication. The particle size and fluorescent colors of the colloidal nanoparticles were tuned by adjusting the reaction temperature. The particle stability and brightness were improved by the addition of dodecanethiol, coating the particle surface with an organic shell. Security patterns were printed on various substrates by applying the screen-printing technique. The patterns were invisible under daylight but observable under UV-light illumination, displaying five different emission colors. By adjusting the concentration of the nanoparticles in the ink, the security patterns were made almost not observable under UV-light illumination but clearly identified by a commercial fiber optics-based spectrometer and a handheld optical device, called a Quantag sensor that was developed in-house. Furthermore, the spectral signatures of barely noticeable patterns are unambiguously validated by the Quantag sensor. Accordingly, low cost and easily applicable anticounterfeiting technology powered by custom-formulated fluorescent inks and a handheld optical instrument are developed to authenticate valuable documents and products.Article Citation - WoS: 12Citation - Scopus: 14Laser Assisted Synthesis of Anisotropic Metal Nanocrystals and Strong Light-Matter Coupling in Decahedral Bimetallic Nanocrystals(Royal Society of Chemistry, 2021) Balcı, Fadime Mert; Balcı, Sinan; Polat, Nahit; Güvenç, Çetin Meriç; Karadeniz, Uğur; Tertemiz, Necip Ayhan; Balcı, Sinan; 04.04. Department of Photonics; 04.01. Department of Chemistry; 04. Faculty of Science; 01. Izmir Institute of TechnologyThe advances in colloid chemistry and nanofabrication allowed us to synthesize noble monometallic and bimetallic nanocrystals with tunable optical properties in the visible and near infrared region of the electromagnetic spectrum. In the strong coupling regime, surface plasmon polaritons (SPPs) of metal nanoparticles interact with excitons of quantum dots or organic dyes and plasmon-exciton hybrid states called plexcitons are formed. Until now, various shaped metal nanoparticles such as nanorods, core-shell nanoparticles, hollow nanoparticles, nanoprisms, nanodisks, nanorings, and nanobipyramids have been synthesized to generate plasmon-exciton mixed states. However, in order to boost plasmon-exciton interaction at nanoscale dimensions and expand the application of plexcitonic nanocrystals in a variety of fields such as solar cells, light emitting diodes, and nanolasers, new plexcitonic nanocrystals with outstanding optical and chemical properties remain a key goal and challenge. Here we report laser-assisted synthesis of decahedral shaped noble metal nanocrystals, tuning optical properties of the decahedral shaped nanocrystals by galvanic replacement reactions, colloidal synthesis of bimetallic decahedral shaped plexcitonic nanocrystals, and strong plasmon-plasmon interaction in bimetallic decahedral shaped noble metal nanocrystals near a metal film. We photochemically synthesize decahedral Ag nanoparticles from spherical silver nanoparticles by using a 488 nm laser. The laser assisted synthesis of silver nanoparticles yields decahedral (bicolored) and prism (monocolored) shaped silver nanocrystals. The decahedral shaped nanoparticles were selectively separated from prism shaped nanoparticles by centrifugation. The optical properties of decahedral nanocrystals were tuned by the galvanic replacement reaction between gold ions and silver atoms. Excitons of J-aggregate dyes and SPPs of decahedral bimetallic nanoparticles strongly couple and hence decahedral shaped plexcitonic nanoparticles are prepared. In addition, localized SPPs of decahedral shaped bimetallic nanocrystals interact strongly with the propagating SPPs of a flat silver film and hence new hybrid plasmonic modes (plasmonic nanocavities) are generated. The experimental results are further fully corroborated by theoretical calculations including decahedral shaped plexcitonic nanoparticles and decahedral nanoparticles coupled to flat metal films.Article Citation - WoS: 22Citation - Scopus: 20Fokas Method for Linear Boundary Value Problems Involving Mixed Spatial Derivatives(Royal Society of Chemistry, 2020) Fokas, A. S.; Özsarı, Türker; Batal, Ahmet; Batal, Ahmet; Özsarı, Türker; 04.02. Department of Mathematics; 04. Faculty of Science; 01. Izmir Institute of TechnologyWe obtain solution representation formulae for some linear initial boundary value problems posed on the half space that involve mixed spatial derivative terms via the unified transform method (UTM), also known as the Fokas method. We first implement the method on the second-order parabolic PDEs; in this case one can alternatively eliminate the mixed derivatives by a linear change of variables. Then, we employ the method to biharmonic problems, where it is not possible to eliminate the cross term via a linear change of variables. A basic ingredient of the UTM is the use of certain invariant maps. It is shown here that these maps are well defined provided that certain analyticity issues are appropriately addressed.Article Citation - WoS: 6Citation - Scopus: 6Novel Ultra-Thin Two-Dimensional Structures of Strontium Chloride(Royal Society of Chemistry, 2020) Akyol, Cansu; Şahin, Hasan; Başkurt, Mehmet; Şahin, Hasan; 04.04. Department of Photonics; 04. Faculty of Science; 01. Izmir Institute of TechnologyBy performing density functional theory-based calculations, possible stable ultra-thin crystal structures of SrCl(2)are investigated. Phonon calculations reveal that, among the possible crystal structures, three different phases; namely 1H, 1T, and square, are dynamically stable. In addition,ab initiomolecular dynamics calculations show that these three phases are thermally stable up to well above room temperature. Another important stability factor of crystals, the chemical inertness against abundant molecules in the atmosphere, such as N-2, O-2, H2O, and CO2, is also investigated. The analysis shows that SrCl(2)single-layers are chemically stable against these molecules. Moreover, it is determined that in contact with H2O and CO2, ultra-thin SrCl(2)sheets display unique electronic features, allowing them to be used in sensing applications. It is also shown that single layers of SrCl(2)crystals, all having a wide electronic band gap, can form type-I and type-II vertical van der Waals heterostructures with well-known 2D materials such as MoS2, WSe2, and h-BN.