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Article Citation - WoS: 5Citation - Scopus: 8Calcium Carbonate/Polydopamine Composite Nanoplatform Based on Tgf-Β Blockade for Comfortable Cancer Immunotherapy(Amer Chemical Soc, 2024) Li, Yunmeng; Wang, Deqiang; Sun, Jian; Hao, Zhaokun; Tang, Letian; Sun, Wanru; Wang, RanranCancer pain seriously reduces the quality of life of cancer patients. However, most research about cancer focuses solely on inhibiting tumor growth, neglecting the issue of cancer pain. Therefore, the development of therapeutic agents with both tumor suppression and cancer pain relief is crucial to achieve human-centered treatment. Here, the work reports curcumin (CUR) and ropivacaine (Ropi) coincorporating CaCO3/PDA nanoparticles (CaPNMCUR+Ropi) that realized efficient tumor immunotherapy and cancer pain suppression. The therapeutic efficiency and mechanism are revealed in vitro and in vivo. The results indicate that CaPNMCUR+Ropi underwent tumor microenvironment-responsive degradation and realized rapid release of calcium ions, Ropi, and CUR. The excessive intracellular calcium triggered the apoptosis of tumor cells, and the transient pain caused by the tumor injection was relieved by Ropi. Simultaneously, CUR reduced the levels of immunosuppressive factor (TGF-beta) and inflammatory factor (IL-6, IL-1 beta, and TNF-alpha) in the tumor microenvironment, thereby continuously augmenting the immune response and alleviating inflammatory pain of cancer animals. Meanwhile, the decrease of TGF-beta leads to the reduction of transient receptor potential vanilloid 1 (TRPV1) expression, thereby alleviating hyperalgesia and achieving long-lasting analgesic effects. The design of the nanosystem provides a novel idea for human-centered tumor treatment in the future.Conference Object Antibacterial Activity of Cubic Boron Nitride (cbn) Coatings on Stainless Steel Grade 316 (316l)(Amer Chemical Soc, 2010) Uzunoglu, Emel; Sengonul, Merih; Derici, Kursat; Biriken, Derya; Kaftanoglu, Bilgin; Sengonul, Merih[No Abstract Available]Article Citation - WoS: 47Citation - Scopus: 52Biocompatible Electroactive Tetra(aniline)-Conjugated Peptide Nanofibers for Neural Differentiation(Amer Chemical Soc, 2018) Arioz, Idil; Erol, Ozlem; Bakan, Gokhan; Dikecoglu, F. Begum; Topal, Ahmet E.; Urel, Mustafa; Guler, Mustafa O.Peripheral nerve injuries cause devastating problems for the quality of patients' lives, and regeneration following damage to the peripheral nervous system is limited depending on the degree of the damage. Use of nanobiomaterials can provide therapeutic approaches for the treatment of peripheral nerve injuries. Electroactive biomaterials, in particular, can provide a promising cure for the regeneration of nerve defects. Here, a supramolecular electroactive nanosystem with tetra(aniline) (TA)-containing peptide nanofibers was developed and utilized for nerve regeneration. Self-assembled TA conjugated peptide nanofibers demonstrated electroactive behavior. The electroactive self-assembled peptide nanofibers formed a well-defined three-dimensional nanofiber network mimicking the extracellular matrix of the neuronal cells. Neurite outgrowth was improved on the electroactive TA nanofiber gels. The neural differentiation of PC-12 cells was more advanced on electroactive peptide nanofiber gels, and these biomaterials are promising for further use in therapeutic neural regeneration applications.Article Citation - WoS: 52Citation - Scopus: 57Members of Cmy Color Space: Cyan and Magenta Colored Polymers Based on Oxadiazole Acceptor Unit(Amer Chemical Soc, 2012) Ozkut, Merve Icli; Algi, Melek Pamuk; Oztas, Zahide; Algi, Fatih; Onal, Ahmet M.; Cihaner, AtillaIn this study, three novel oxadiazole-based polymers were synthesized and their electrochemical and optical properties were investigated. The polymers were found to have both p- and n-type doping properties accompanied by electrochromic response. Two polymer films exhibit cyan and magenta colors, which constitute two legs of CMY color spaces, in their neutral states and they are soluble in common-organic solvents. According to the color mixing theory, all colors in the visible spectrum including black color can be obtained by using these polymers with a yellow colored electrochromic polymer. Among these polymers, the polymer bearing propyledioxythiophene donor units has some superior properties like high stability (it retains 94% of its electroactivity after 2000 cycles), solubility, and high coloration efficiency (230 cm(2)/C), whereas as expected ethylenedioxythiophene containing one has the lowest band gap as 1.08 eV.Article Citation - WoS: 24Citation - Scopus: 24Complete Dehydrogenation of Hydrazine Borane on Manganese Oxide Nanorod-Supported Ni@ir Core-Shell Nanoparticles(Amer Chemical Soc, 2020) Yurderi, Mehmet; Top, Tuba; Bulut, Ahmet; Kanberoglu, Gulsah Saydan; Kaya, Murat; Zahmakiran, MehmetHydrazine borane (HB; N2H4BH3) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni-0.22@Ir-0.78/OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h(-1) at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni-0.22@Ir-0.78/OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni-0.22@Ir-0.78/OMS-2-catalyzed dehydrogenation of HB.Article Citation - WoS: 61Fast Neutron Imaging With Semiconductor Nanocrystal Scintillators(Amer Chemical Soc, 2020) McCall, Kyle M.; Sakhatskyi, Kostiantyn; Lehmann, Eberhard; Walfort, Bernhard; Losko, Adrian S.; Montanarella, Federico; Kovalenko, Maksym, VFast neutrons offer high penetration capabilities for both light and dense materials due to their comparatively low interaction cross sections, making them ideal for the imaging of large-scale objects such as large fossils or as-built plane turbines, for which X-rays or thermal neutrons do not provide sufficient penetration. However, inefficient fast neutron detection limits widespread application of this technique. Traditional phosphors such as ZnS:Cu embedded in plastics are utilized as scintillators in recoil proton detectors for fast neutron imaging. However, these scintillation plates exhibit significant light scattering due to the plastic-phosphor interface along with long-lived afterglow (on the order of minutes), and therefore alternative solutions are needed to increase the availability of this technique. Here, we utilize colloidal nanocrystals (NCs) in hydrogen-dense solvents for fast neutron imaging through the detection of recoil protons generated by neutron scattering, demonstrating the efficacy of nanomaterials as scintillators in this detection scheme. The light yield, spatial resolution, and neutron-vs-gamma sensitivity of several chalcogenide (CdSe and CuInS2)-based and perovskite halide-based NCs are determined, with only a short-lived afterglow (below the order of seconds) observed for all of these NCs. FAPbBr(3) NCs exhibit the brightest total light output at 19.3% of the commercial ZnS:Cu(PP) standard, while CsPbBrCl2:Mn NCs offer the best spatial resolution at similar to 2.6 mm. Colloidal NCs showed significantly lower gamma sensitivity than ZnS:Cu; for example, 79% of the FAPbBr(3) light yield results from neutron-induced radioluminescence and hence the neutron-specific light yield of FAPbBr(3) is 30.4% of that of ZnS:Cu(PP). Concentration and thickness-dependent measurements highlight the importance of increasing concentrations and reducing self-absorption, yielding design principles to optimize and foster an era of NC-based scintillators for fast neutron imaging.Article Citation - WoS: 15Metal-Salt Enhanced Grafting of Vinylpyridine and Vinylimidazole Monomer Combinations in Radiation Grafted Membranes for High-Temperature PEM Fuel Cells(Amer Chemical Soc, 2020) Mojarrad, Naeimeh Rajabalizadeh; Sadeghi, Sahl; Kaplan, Begum Yarar; Guler, Enver; Gursel, Selmiye AlkanProton exchange membranes were prepared and characterized for utilization in high-temperature proton exchange membrane fuel cells, HT-PEMFCs. 1-vinylimidazole (1-VIm) and 4-vinylpyridine (4VP) monomers were simultaneously grafted onto pre-irradiated ETFE (ethylene-co-tetrafluoroethylene) films which were prepared using gamma-rays with a dose of 100 kGy, as a robust substrate to prepare acid-base composite membranes. The grafting reaction was performed at 60 degrees C for 24 h followed by protonation via phosphoric acid doping in the subsequent step. The effect of adding ferrous salts as promoters in grafting was investigated by characterization of resultant membranes via thermal gravimetric analysis and mechanical tests. The fuel cell tests were conducted under different relative humidities (RHs) and applied temperatures. Membranes prepared with salt addition exhibited superior proton conductivities. Results including up to 80 mS cm(-1) conductivity at 110 degrees C in 60% RH and excellent thermal stability, even at 300 degrees C, suggest these membranes are promising for HT-PEMFC applications.Article Citation - WoS: 130Mnox< Pdag Alloy Nanoparticles for the Additive-Free Dehydrogenation of Formic Acid at Room Temperature(Amer Chemical Soc, 2015) Bulut, Ahmet; Yurderi, Mehmet; Karatas, Yasar; Say, Zafer; Kivrak, Hilal; Kaya, Murat; Zahmakiran, MehmetFormic acid (HCOOH) has a great potential as a safe and a convenient hydrogen carrier for fuel cell applications. However, efficient and CO-free hydrogen production through the decomposition of formic acid at low temperatures (<363 K) in the absence of additives constitutes a major challenge. Herein, we present a new heterogeneous catalyst system composed of bimetallic PdAg alloy and MnOx nanoparticles supported on amine-grafted silica facilitating the liberation of hydrogen at room temperature through the dehydrogenation of formic acid in the absence of any additives with remarkable activity (330 mol H-2 center dot mol catalyst(-1)center dot h(-1)) and selectivity (>99%) at complete conversion (>99%). Moreover this new catalytic system enables facile catalyst recovery and very high stability against agglomeration, leaching, and CO poisoning. Through a comprehensive set of structural and functional characterization experiments, mechanistic origins of the unusually high catalytic activity, selectivity, and stability of this unique catalytic system are elucidated. Current heterogeneous catalytic architecture presents itself as an excellent contender for clean hydrogen production via room-temperature additive-free dehydrogenation of formic acid for on-board hydrogen fuel cell applications.Article Citation - WoS: 14Dissociative Adsorption of Water at (211) Stepped Metallic Surfaces by First-Principles Simulations(Amer Chemical Soc, 2017) Pekoz, Rengin; Donadio, DavideSteps at high-index metallic surfaces display higher chemical reactivity than close-packed surfaces and may give rise to selective adsorption and partial dissociation of water. Inspired by differential desorption experiments, we have studied the adsorption and dissociation of water clusters and one-dimensional wires on Pt(211) by density functional theory and molecular dynamics simulations. These calculations reveal that water at the step edges of Pt(211) adsorbs more weakly than at Pt(221), but partial dissociation of adsorbed water clusters is energetically competitive. We observe that the one-dimensional structure proposed experimentally can be realized only by partially dissociated water wires. In addition, weaker adsorption allows the formation of structures in which a number of water molecules detach from the step and form weak hydrogen bonds with the terrace. This study is further extended to the energetics of small water clusters on (211) surfaces of Ir, Rh, and Pd.Article Citation - WoS: 81Citation - Scopus: 86New Approach for the Surface Enhanced Resonance Raman Scattering (serrs) Detection of Dopamine at Picomolar (pm) Levels in the Presence of Ascorbic Acid(Amer Chemical Soc, 2012) Kayat, Murat; Volkan, MurvetThe development of a novel surface-enhanced resonance Raman scattering (SERRS) platform that allows fast and sensitive detection of dopamine (DA) has been reported. The iron-nitrilotriacetic acid attached silver nanoparticle (Ag-Fe(NTA)) substrate provides remarkable sensitivity and reliable repeatability. The advantages of both the surface functionalization for specific analytes and the SERRS are integrated into a single functional unit. While the silver core gives the necessary enhancing properties, the Fe-NTA receptors can trap DA adjacent the silver core and the NTA-Fe-DA complex formed provides resonance enhancement with a 632.8 nm laser. DA could be detected in pM level without any pretreatment with a reliable discrimination against AA, by utilizing low laser power (10 mW) and short data acquisition time (10 s). The high sensitivity along with the improved selectivity of this sensing approach is a significant step toward molecular diagnosis of Parkinson's disease.
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