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Povzetek: One of the challenging aspects of implementing hydrogen is the cost and availability of hydrogen, e.g. green hydrogen is costly and inaccessible, whereas conventional grey hydrogen is associated with substantial CO2 emissions. An intermediate solution could be turquoise hydrogen, which promises substantially lower direct cost and CO2-imposed social cost. This work investigates nickel nanoclusters on iron co-catalyst system, supported by gamma alumina, for the catalytic degradation of methane. A novel synthesis approach is tested to examine the influence of Fe amount on reaction yields and outcomes. Varying amounts of Fe with and without Ni were tested at 700,800, and 900 °C in a batch-type reaction. Analysis of catalysts and outcomes was carried out; it was found that the use of co-catalysts on commercial gamma alumina pyrolysis yields hydrogen at 82% at lower reaction temperatures of 700 °C and 80% at900°C. Addition of Ni nanoclusters provide higher results than those of a single Fe catalyst. The synergistic effect of Ni-Fe catalysts exhibits improved efficiency, yielding a range of valuable nanofibrous carbon tested as pesticide sensors showing promise in extending life cycle of catalyst materials.
Ključne besede: iron-nickel nanoclusters, clean energy, hydrogen, pyrolysis, nanomaterials
Objavljeno v DiRROS: 14.05.2026; Ogledov: 187; Prenosov: 141
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Povzetek: In the present study, two types of graphene quantum dots (GQDs) were investigated: green-emitting (G-GQDs) and blue-emitting (B-GQDs). Physicochemical characterisation was performed using transmission electron microscopy (TEM), zeta potential, and hydrodynamic radius measurements to evaluate the morphology, particle size, aggregation behaviour, and colloidal stability of the GQDs in both water and cell culture medium. G-GQDs exhibited superior colloidal stability and more uniform dispersion than B-GQDs, whereas both types showed reduced aggregation and surface charge in cell culture medium due to protein corona formation. Toxicological characterisation was performed using an in vitro human hepatocellular carcinoma (HepG2) 3D spheroid model, with GQDs exposures up to 250 µg/mL (100 µg/cm2). Cytotoxicity was measured using the CellTiter-Glo luminometric assay, while genotoxicity was evaluated by the comet assay and flow cytometric analysis of γH2AX and phosphorylated histone H3 (p-H3) after 24 h of exposure. Both GQDs induced dose-dependent cytotoxic effects in HepG2 spheroids. At non-cytotoxic concentrations, a dose-dependent increase in DNA damage was observed, as determined by the comet assay. However, no evidence of DNA double-strand breaks (γH2AX) or elevated p-H3 levels was detected, suggesting the absence of clastogenic and aneugenic activity. The observed DNA single-strand breaks may be partly attributed to reactive oxygen species induction. These results indicate that, although GQDs induced cytotoxicity and single-strand DNA damage, no clear evidence of more severe genotoxic effects was observed under the tested conditions. Further studies are warranted to elucidate underlying mechanisms and comprehensively assess the safety profile of GQDs for biomedical applications.
Ključne besede: nanomaterials, graphene quantum dots, HepG2 spheroids, toxicity
Objavljeno v DiRROS: 19.03.2026; Ogledov: 353; Prenosov: 129
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Povzetek: Two-dimensional (2D) nanomaterials with chemical and structural diversity have piqued the interest of the scientific community due to their superior photonic, mechanical, electrical, magnetic, and catalytic capabilities that distinguish them from their bulk counterparts. Among these 2D materials, two-dimensional (2D) transition metal carbides, carbonitrides, and nitrides with a general chemical formula of Mn+1XnTx (where n = 1–3), together known as MXenes, have gained tremendous popularity and demonstrated competitive performance in biosensing applications. In this review, we focus on the cutting-edge advances in MXene-related biomaterials, with a systematic summary on their design, synthesis, surface engineering approaches, unique properties, and biological properties. We particularly emphasize the property–activity–effect relationship of MXenes at the nano– bio interface. We also discuss the recent trends in the application of MXenes in accelerating the performance of conventional point of care (POC) devices towards more practical approaches as the next generation of POC tools. Finally, we explore in depth the existing problems, challenges, and potential for future improvement of MXene-based materials for POC testing, with the goal of facilitating their early realization of biological applications.
Ključne besede: MXenes, 2D nanomaterials, biosensors, POC testing
Objavljeno v DiRROS: 16.12.2025; Ogledov: 504; Prenosov: 309
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Povzetek: The use of omics is gaining importance in the field of nanoecotoxicology; an increasing number of studies are aiming to investigate the effects and modes of action of engineered nanomaterials (ENMs) in this way. However, a systematic synthesis of the outcome of such studies regarding common responses and toxicity pathways is currently lacking. We developed an R-scripted computational pipeline to perform reanalysis and functional analysis of relevant transcriptomic data sets using a common approach, independent from the ENM type, and across different organisms, including Arabidopsis thaliana, Caenorhabditis elegans, and Danio rerio. Using the pipeline that can semiautomatically process data from different microarray technologies, we were able to determine the most common molecular mechanisms of nanotoxicity across extremely variable data sets. As expected, we found known mechanisms, such as interference with energy generation, oxidative stress, disruption of DNA synthesis, and activation of DNA-repair but also discovered that some less-described molecular responses to ENMs, such as DNA/RNA methylation, protein folding, and interference with neurological functions, are present across the different studies. Results were visualized in radar charts to assess toxicological response patterns allowing the comparison of different organisms and ENM types. This can be helpful to retrieve ENM-related hazard information and thus fill knowledge gaps in a comprehensive way in regard to the molecular underpinnings and mechanistic understanding of nanotoxicity.
Ključne besede: gene expression, nanomaterials
Objavljeno v DiRROS: 19.07.2024; Ogledov: 1219; Prenosov: 835
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