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Article Citation - WoS: 8Citation - Scopus: 9Expanding the Role of Exosomes in Drug, Biomolecule, and Nanoparticle Delivery(Pergamon-elsevier Science Ltd, 2025) Saka, Ongun Mehmet; Dora, Devrim Demir; Kibar, Gunes; Tevlek, AtakanExosomes are nanoscale extracellular vesicles released by diverse cell types, serving essential functions in intercellular communication and physiological processes. These vesicles have garnered considerable interest in recent years for their potential as drug delivery systems, attributed to their natural origin, minimal immunogenicity, high biocompatibility, and capacity to traverse biological barriers, including the blood-brain barrier. Exosomes can be obtained from diverse biological fluids, rendering them accessible and versatile vehicles for therapeutic medicines. This study emphasizes the burgeoning significance of exosomes in drug administration, concentrating on their benefits, including improved stability, target selectivity, and the capacity to encapsulate various biomolecules, such as proteins, nucleic acids, and small molecules. Notwithstanding their potential applications, other problems remain, including as effective drug loading, industrial scalability, and the standardization of isolation methodologies. Overcoming these hurdles via new research is essential for fully harnessing the promise of exosomes in therapeutic applications, especially in the treatment of intricate diseases like cancer and neurological disorders.Article Citation - WoS: 150Citation - Scopus: 152Pd-mnox< Nanoparticles Dispersed on Amine-Grafted Silica: Highly Efficient Nanocatalyst for Hydrogen Production From Additive-Free Dehydrogenation of Formic Acid Under Mild Conditions(Elsevier Science Bv, 2015) Bulut, Ahmet; Yurderi, Mehmet; Karatas, Yasar; Zahmakiran, Mehmet; Kivrak, Hilal; Gulcan, Mehmet; Kaya, MuratHerein we report the development of a new highly active, selective and reusable nanocatalyst for additive-free dehydrogenation of formic acid (HCOOH), which has great potential as a safe and convenient hydrogen carrier for fuel cells, under mild conditions. The new catalyst system consisting of bimetallic Pd-MnOx nanoparticles supported on aminopropyl functionalized silica (Pd-MnOx/SiO2-NH2) was simply and reproducibly prepared by deposition-reduction technique in water at room temperature. The characterization of Pd-mnO(x)/SiO2-NH2 catalyst was done by the combination of multipronged techniques, which reveals that the existence of highly crystalline individually nucleated Pd(0) and MnOx nanoparticles (d(mean) = 4.6 +/- 1.2 nm) on the surface of aminopropyl functionalized silica. These supported Pd-MnOx nanoparticles can catalyze the additive-free dehydrogenation of formic acid with record activity (TOF = 1300 h(-1)) at high selectivity (>99%) and conversion (>99%) under mild conditions (at 50 degrees C and under air). Moreover, easy recovery plus high durability of these supported Pd-MnOx nanoparticles make them a reusable heterogeneous catalyst in the additive-free dehydrogenation of formic acid. (C) 2014 Elsevier B.V. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 4A Simple Method To Set the Spray Properties for Flame Spray Pyrolysis Production of Nanoparticles(Elsevier Sci Ltd, 2020) Alhaleeb, Mustafi A.; Machin, Nesrin E.The most critical part of the flame spray pyrolysis (FSP) process is the nozzle, since it plays a key role in setting the spray properties. In this study, we developed an approach to adjust the nozzle throat gap size for a desired dispersion gas flow rate and upstream pressure, based on the external size and shape of a two phase external mixing nozzle. An equation was derived and validated by comparing the predicted gas flow rates with the data provided in a commercial nozzle supplier chart. Experiments were also conducted in our lab-scale FSP reactor to test the validity of the predictions. The approach developed here was found to closely predict the gap size necessary to pass the required dispersion gas flow at a desired pressure drop. Error in predictions was found to be less than 3% at an upstream pressure range of 3-10 bars. The isentropic flow assumption for perfect gases across the convergent-divergent nozzle was found to fail below 2 bars, consistent with the theory applied. By using the method here, the nozzle setting for a desired operation in an FSP process can be easily done, minimizing the time-consuming trial and error steps needed otherwise.Article Citation - WoS: 141Citation - Scopus: 147Carbon Dispersed Copper-Cobalt Alloy Nanoparticles: a Cost-Effective Heterogeneous Catalyst With Exceptional Performance in the Hydrolytic Dehydrogenation of Ammonia-Borane(Elsevier, 2016) Bulut, Ahmet; Yurderi, Mehmet; Ertas, Ilknur Efecan; Celebi, Metin; Kaya, Murat; Zahmakiran, MehmetHerein, we report the development of a new and cost-effective nanocatalyst for the hydrolytic dehydrogenation of ammonia-borane (NH3BH3), which is considered to be one of the most promising solid hydrogen carriers due to its high gravimetric hydrogen storage capacity (19.6 wt%) and low molecular weight. The new catalyst system consisting of bimetallic copper-cobalt alloy nanoparticles supported on activated carbon was simply and reproducibly prepared by surfactant-free deposition-reduction technique at room temperature. The characterization of this new catalytic material was done by the combination of multi-pronged techniques including ICP-MS, XRD, XPS, BFTEM, HR-TEM, STEM and HAADF-STEM-line analysis. The sum of their results revealed that the formation of copper-cobalt alloy nanoparticles (d(mean) =1.8 nm) on the surface of activated carbon (CuCo/C). These new carbon supported copper-cobalt alloy nanoparticles act as highly active catalyst in the hydrolytic dehydrogenation of ammonia-borane, providing an initial turnover frequency of TOF = 2700 h(-1) at 298 K, which is not only higher than all the non-noble metal catalysts but also higher than the majority of the noble metal based homogeneous and heterogeneous catalysts employed in the same reaction. More importantly, easy recovery and high durability of these supported CuCo nanoparticles make CuCo/C recyclable heterogeneous catalyst for the hydrolytic dehydrogenation of ammonia-borane. They retain almost their inherent activity even at 10th catalytic reuse in the hydrolytic dehydrogenation of ammonia-borane at 298K. (C) 2015 Elsevier B.V. All rights reserved.Article Citation - WoS: 15Citation - Scopus: 15Targeted mesoporous silica nanoparticles for improved inhibition of disinfectant resistant Listeria monocytogenes and lower environmental pollution(Elsevier, 2021) Sudagidan, Mert; Yildiz, Gulsah; Onen, Selin; Al, Rabia; Temiz, S. Sevval Nur; Yurt, Mediha Nur Zafer; Ozalp, Veli C.Benzalkonium chloride (BAC) is a common ingredient of disinfectants used for industrial, medical, food safety and domestic applications. It is a common pollutant detected in surface and wastewaters to induce adverse effects on Human health as well as aquatic and terrestrial life forms. Since disinfectant use is essential in combatting against microorganisms, the best approach to reduce ecotoxicity level is to restrict BAC use. We report here that encapsulation of BAC in mesoporous silica nanoparticles can provide an efficient strategy for inhibition of mi-crobial activity with lower than usual concentrations of disinfectants. As a proof-of-concept, Listeria mono-cytogenes was evaluated for minimum inhibitory concentration (MIC) of nanomaterial encapsulated BAC. Aptamer molecular gate structures provided a specific targeting of the disinfectant to Listeria cells, leading to high BAC concentrations around bacterial cells, but significantly reduced amounts in total. This strategy allowed to inhibition of BAC resistant Listeria strains with 8 times less the usual disinfectant dose. BAC encapsulated and aptamer functionalized silica nanoparticles (AptBACNP) effectively killed only target bacteria L. monocytogenes, but not the non-target cells, Staphylococcus aureus or Escherichia coli. AptBACNP was not cytotoxic to Human cells as determined by in vitro viability assays.Article Citation - WoS: 148Citation - Scopus: 152Carbon Supported Trimetallic Pdniag Nanoparticles as Highly Active, Selective and Reusable Catalyst in the Formic Acid Decomposition(Elsevier Science Bv, 2014) Yurderi, Mehmet; Bulut, Ahmet; Zahmakiran, Mehmet; Kaya, MuratTrimetallic PdNiAg nanoparticles supported on activated carbon were simply and reproducibly prepared by wet-impregnation followed by simultaneous reduction method without using any stabilizer at room temperature. The characterization of the resulting material was done by the combination of complimentary techniques and the sum of their results shows that the formation of well-dispersed 5.6 +/- 2.2 nm PdNiAg nanoparticles in alloy form on the surface of activated carbon. These carbon supported PdNiAg nanoparticles were employed as heterogeneous catalyst in the catalytic decomposition of formic acid, which has great potential as a safe and convenient hydrogen carrier for fuel cells, under mild conditions. It was found that PdNiAg/C can catalyze the dehydrogenation of formic acid with high selectivity (similar to 100%) and activity (TOF = 85 h(-1)) at 50 degrees C. More importantly, the exceptional stability of PdNiAg nanoparticles against to agglomeration, leaching and CO poisoning make PdNiAg/C reusable catalyst in the formic acid dehydrogenation. PdNiAg/C catalyst retains almost its inherent activity (>94%) even at 5th reuse in the dehydrogenation of formic acid with high selectivity (similar to 100%) at complete conversion. The work reported here also includes the compilation of kinetic data for PdNiAg/C catalyzed dehydrogenation of formic acid depending on catalyst [PdNiAg], substrate [HCOOH], promoter [HCOONa] concentrations and temperature to determine the rate expression and the activation parameters (Ea, Delta H-#, and Delta S-#) of the catalytic reaction. (C) 2014 Elsevier B.V. All rights reserved.
