WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 3Citation - Scopus: 3Light-Induced Synthesis of Single-Crystalline Gold Microplates in an Open System(Amer Chemical Soc, 2023) Akkuş, Betül; Mert Balcı, FadimeBottom-up synthesis of large single-crystalline gold microplates is of key importance to catalysis, nanophotonics, bioengineering, and plasmonics. However, easy, low-cost, room-temperature, and high-yield synthesis of large gold microplates with several micrometers in lateral size and a few tens of nanometers in thickness by using photochemical synthesis in an open system is still challenging. We herein report on an easy and cost-effective photochemical synthesis of single-crystalline gold microplates with lateral sizes up to around 40 mu m and tens of nanometers in thickness in a few hours of reaction time in an open system containing a lyotropic liquid crystal, which is formed by self-assembly of 10-lauryl ether in a strong acid, sulfuric acid, along with water. We have found that by changing the reaction parameters, such as the reaction time, the concentration of gold ions in the liquid crystal, etc., the thickness and size of the microplates can be easily controlled. Most importantly, the liquid crystalline phase is completely preserved after completion of the photochemical reaction. The microplates can be easily isolated and transferred to different media such as alcohol and water for further studies, or they can be immediately used on a substrate after completion of the reaction. The results obtained in this study will allow us to understand the growth mechanism of gold microplates in open systems, and they will find applications in a variety of critical areas, such as plasmonics, nanophotonics, and catalysis.Review Citation - WoS: 6Citation - Scopus: 8Molecular Trojan Horses for Treating Lysosomal Storage Diseases(Academic Press, 2023) Leal, Andres Felipe; Rintz, Estera; Çelik, Betül; Ago, Yasuhiko; León, Daniel; İnci, Orhan Kerim; Seyrantepe, VolkanLysosomal storage diseases (LSDs) are caused by monogenic mutations in genes encoding for proteins related to the lysosomal function. Lysosome plays critical roles in molecule degradation and cell signaling through interplay with many other cell organelles, such as mitochondria, endoplasmic reticulum, and peroxisomes. Even though several strategies (i.e., protein replacement and gene therapy) have been attempted for LSDs with promising results, there are still some challenges when hard-to-treat tissues such as bone (i.e., cartilages, ligaments, meniscus, etc.), the central nervous system (mostly neurons), and the eye (i.e., cornea, retina) are affected. Consistently, searching for novel strategies to reach those tissues remains a priority. Molecular Trojan Horses have been well-recognized as a potential alternative in several pathological scenarios for drug delivery, including LSDs. Even though molecular Trojan Horses refer to genetically engineered proteins to overcome the blood-brain barrier, such strategy can be extended to strategies able to transport and deliver drugs to specific tissues or cells using cell-penetrating peptides, monoclonal antibodies, vesicles, extracellular vesicles, and patient-derived cells. Only some of those platforms have been attempted in LSDs. In this paper, we review the most recent efforts to develop molecular Trojan Horses and discuss how this strategy could be implemented to enhance the current efficacy of strategies such as protein replacement and gene therapy in the context of LSDs. © 2023Article Citation - WoS: 1Citation - Scopus: 1Epoxy Matrix Nano Composites: Modulus, Strength and Ductility Enhancement Through Auxeticity of Α-Cristobalite Filler(Elsevier, 2023) Güden, Mustafa; Ülker, Sevkan; Movahedi, NimaThe negative Poisson's ratio (NPR) nano-size ?-Cristobalite particle/epoxy composites were prepared and tensile tested. The elastic modulus and strength of the composites were improved as the particle volume fraction increased from 0 to 0.02. Unlike the conventional particle reinforced composites, the fracture strain increased with the nano ?-Cristobalite addition, an effect which was ascribed to the intrinsic NPR behavior of the filler. © 2023 Elsevier B.V.Article Citation - WoS: 4Citation - Scopus: 4Optimizing the Dispersion of Calcium Phosphate Nanoparticles for Cellular Studies Using Statistical Design of Experiments(Elsevier, 2023) Önder, Anıl Can; Tomak, Aysel; Öksel Karakuş, CeydaThe in vitro experimentation of ceramic nanoparticles often requires their dispersion in liquid media without causing particle clumps or deteriorating sample integrity. However, the dispersion of nanoparticles using the available protocols rarely leads to stable and uniform dispersions which, in turn, raises concerns about the validity, repeatability and comparability of the findings observed in vitro. Moreover, the ability to control the final dispersion quality of ceramic nanoparticles is an essential step to obtaining optimized nanoceramic materials with desired functionality and to enhancing their performance in subsequent applications. While the need to have a comprehensive guideline for the dispersion of nanoparticles has led to several published documents and protocols, the dispersion methodology of ceramic nanoparticles and the relative contribution of the experimental parameters to the quality of resulting dispersion are still not clear. Here, we employed the statistical design of experiment (DoE) approach to systematically assess the magnitude and source of variation in dispersion quality of two different ceramic nanoparticles, hydroxyapatite and tricalcium phosphate. Using the first-order Plackett-Burman Design (PBD), nanoparticle concentration, pH and the presence of an additive were identified as the most critical factors influencing the resulting hydrodynamic size and zeta potential of the ceramic nanoparticles. Optimization using a second-order Central Composite Design (CCD) yielded a set of quadratic regression equations that were used to predict the hydrodynamic size or zeta potential of ceramic nanoparticles with high accuracy (R2, 0.88–0.92). The results of PBD screening and CCD optimization experiments were employed to prepare nanoparticle dispersions of different quality, which were then used to compare the effect of aggregation on the viability of human osteosarcoma (SaOS-2) cells. Overall, the results of this study provided insight into the role that various experimental parameters play in the colloidal stability and dispersion of ceramic nanoparticles. © 2023Article Citation - WoS: 11Citation - Scopus: 11Enhanced Electrocaloric Effect of P(vdf-Trfe) Nanocomposites With Ca and Sn Co-Doped Batio3 Particles(Elsevier, 2023) Tokkan, Melike; Demir, Mustafa M.; Adem, UmutWe report on the enhancemenent of electrocaloric effect in solution cast polymer nanocomposites based on Poly (vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE) 55-45] with Ca and Sn co-substituted BaTiO3 ceramic fillers (Ba0.94Ca0.06Ti0.925Sn0.075O3, BCST). Saturated hysteresis loops and normal ferroelectric behaviour of the copolymer-based nanocomposites-as opposed to the relaxor ferroelectric nature of the terpolymer-based ones-allow the utilization of the indirect method to estimate the electrocaloric properties. Both the dielectric constant and electrocaloric temperature change (AT) increases as the particle content increases. Maximum adiabatic temperature change was obtained as 6.96 K under 900 kV/cm for the 10 vol % BCST containing polymer composite around the Curie temperature of the copolymer (70 degrees C). This relatively large electrocaloric strength is slightly lower than those obtained for terpolymer-based nanocomposites.Article Effects of Span 60 Template and Freeze Drying on Zinc Borate Produced From Zinc Nitrate Hexahydrate and Borax Decahydrate(Taylor and Francis Ltd., 2022) Alp, Burcu; Gönen, Mehmet; Atakul Savrık, Sevdiye; Balköse, DevrimZinc borate is an important additive to polymers and lubricants. The process variables such as reactant concentration, presence of template in precipitating medium and drying method determine the composition and particle size of zinc borates. In the present study, zinc borate precipitate obtained by mixing aqueous zinc nitrate and borax decahydrate solutions was dried either by conventional method or by freeze drying. The products were well characterized by advanced methods. Zinc borate from 1 mol dm(-3) reactants had (2.1 +/- 0.5)x(2.5 +/- 0.5)x(1.3 +/- 0.2) mu m and (0.5 +/- 0.1)x(1.3 +/- 0.1)x(0.028 +/- 0.01) mu m dimensions by conventional and freeze drying respectively. Individual particles smaller in size is obtained since the particles are not agglomerated due to absence of surface tension of liquid water for case of freeze drying. Planar particles agglomerated into 20 to 60 mu m crystals in the presence of template Span 60 in 1 mol dm(-3) reactants for conventional drying. Nano zinc borate particles with primary particle size of (46 +/- 9) nm were obtained by decreasing the reactant concentration to 0.1 mol dm(-3). The primary particle size was decreased to (40 +/- 3) nm by addition of Span 60 to dilute solutions. However zinc borate nanoparticles obtained from dilute solutions adhered to each other forming agglomerates during conventional drying. Their freeze drying would allow formation of a freely flowing nano powder.Article Citation - WoS: 15Citation - Scopus: 13Cascade Therapy With Doxorubicin and Survivin-Targeted Tailored Nanoparticles: an Effective Alternative for Sensitization of Cancer Cells To Chemotherapy(Elsevier Ltd., 2019) Dağlıoğlu, Cenk; Kacı, Fatma NecmiyeChemotherapy frequently involves combination treatment protocols to maximize tumor cell killing. Unfortunately these intensive chemotherapeutic regimes, often show disappointing results due to the development of drug resistance and higher nonspecific toxicity on normal tissues. In cancer treatment, it is critically important to minimize toxicity while preserving efficacy. We have previously addressed this issue and proposed a nanoparticle-based combination therapy involving both a molecularly targeted therapy and chemotherapeutic agent for neutralizing antiapoptotic survivin (BIRC5) to potentiate the efficacy of doxorubicin (DOX). Although the particles exhibited strong anticancer effect on the lung carcinoma A549 and the cervical carcinoma HeLa cells, there were lower-level therapeutic outcomes on the colon carcinoma HCT-116, the leukemia Jurkat and the pancreatic carcinoma MIA PaCa-2 cells. Since targeted therapies are one of the key approaches for overcoming drug resistance, tailoring the treatment of cancer cells with distinct characteristics is necessary to improve the therapeutic outcome of cancer therapy and to minimize potential pharmacokinetic interactions of drugs. In the light of this issue, this study examined whether a cascade therapy with low-dose DOX and survivin-targeted tailored nanoparticles is more effective at sensitizing HCT-116, Jurkat and MIA PaCa-2 cancer cells to DOX-chemotherapy than simultaneous combination therapy. The results demonstrated that the sequential therapy with the protocol comprising addition of the nanoparticles after incubation of cells with DOX clearly advanced the therapeutic outcome of related cancer cells, whereas the reverse protocol resulted in a reduction or delay in apoptosis, emphasizing the critical importance of formulating synergistic drug combinations in cancer therapy.