@article{MTMT:35302966, title = {Star-shaped flexible arm multivalent aptamers for largely improved virus binding affinity}, url = {https://m2.mtmt.hu/api/publication/35302966}, author = {Simon, László Ferenc and Szakács, Zoltán and Gyurcsányi, Ervin Róbert}, doi = {10.1016/j.snb.2024.136520}, journal-iso = {SENSOR ACTUAT B CHEM}, journal = {SENSORS AND ACTUATORS B-CHEMICAL}, volume = {422}, unique-id = {35302966}, issn = {0925-4005}, abstract = {Here we explore the click chemistry-based synthesis of high affinity multivalent aptamers and their application for virus detection. In contrast to attempts based on rigid constructs, such as aptamer-modified nanoparticles or hybridization-connected constructs, we propose highly flexible “star-shaped” multivalent aptamers to facilitate the cooperative binding to randomly distributed viral proteins on the surface of pleomorphic viruses such as the respiratory syncytial virus (RSV). Polyethylene glycols (PEGs) with 4 azide terminated flexible arms spanning from a pentaerythritol core were conjugated to aptamer strands with dibenzocyclooctyne and a fluorescent label at their, 3’ and 5’ terminus, respectively. By controlling the aptamer - PEG ratio and following electrophoretic separation all the different valency aptamer conjugates could be prepared. For proof of concept, we used an aptamer selected for the G protein of RSV. We show that significantly higher apparent affinities can be obtained by using multivalent aptamers for both the G protein and RSV virus than with the single stranded aptamer, i.e. with up to ca. 2 orders of magnitude. The inherent convenience of synthesizing fluorescently labelled multivalent aptamers leads to a versatile class of affinity ligands for sensing as demonstrated through the improved detection sensitivity of tetravalent aptamer tagged RSV by fluorescence nanoparticle tracking analysis. © 2024 The Authors}, keywords = {Fluorescence Polarization; RESPIRATORY SYNCYTIAL VIRUS; avidity; Fluorescent nanoparticle tracking analysis; Multivalent aptamers}, year = {2025}, eissn = {0925-4005}, orcid-numbers = {Gyurcsányi, Ervin Róbert/0000-0002-9929-7865} } @article{MTMT:35264601, title = {Comparison of 624-type Capillary Columns II : "Equivalent Columns" Deviation in the Quantitative Analysis}, url = {https://m2.mtmt.hu/api/publication/35264601}, author = {Mátyási, Judit and Nyerges, Gyula and Balla, József}, doi = {10.3311/PPch.37088}, journal-iso = {PERIOD POLYTECH CHEM ENG}, journal = {PERIODICA POLYTECHNICA-CHEMICAL ENGINEERING}, unique-id = {35264601}, issn = {0324-5853}, abstract = {The present paper is the continuation of our "equivalent column" study. 624-type columns were investigated in a capillary gas chromatograph with a flame ionization detector (FID). In the preceding work, we used a homemade test mixture containing mainly acidic type compounds, which we complemented in the current study with additional basic test compounds to give a more precise description of the behaviour of the stationary phases. The columns had the same dimensions (30 m x 0.32 mm x 1.0 mu m; length, internal diameter and film thickness, respectively) but were purchased from different manufacturers or the same manufacturer but from different batches. In addition, also their pre-life was different. These circumstances influence the condition of the stationary phase, and therefore their separation ability. These factors imply the necessity of testing the column from time to time. To distinguish between the separation ability of the columns, we compared the chromatograms, the retention times and retention order of the molecules, as well as peak asymmetry factors. Besides these parameters, quantitative determination is also performed based on the results of separation. We used the effective carbon number (ECN) ECN ) and the limit of quantitation (LoQ) LoQ ) to demonstrate these differences which are caused by the different stationary phase conditions.}, keywords = {STATIONARY PHASES; COEFFICIENTS; Response factors; Flame ionization detector; Effective carbon number; Column test; 624 capillary column}, year = {2024}, eissn = {1587-3765} } @article{MTMT:35264584, title = {On how scientists communicate with their peers}, url = {https://m2.mtmt.hu/api/publication/35264584}, author = {Hargittai, István}, doi = {10.1007/s11224-024-02371-9}, journal-iso = {STRUCT CHEM}, journal = {STRUCTURAL CHEMISTRY}, unique-id = {35264584}, issn = {1040-0400}, keywords = {Chemistry, Physical; Chemistry, Multidisciplinary}, year = {2024}, eissn = {1572-9001} } @article{MTMT:35218095, title = {Covalently Modified Molecular-Recognition-Capable UV-Transparent Microplate for Ultra-High-Throughput Screening of Dissolved Zn2+ and Pb2+}, url = {https://m2.mtmt.hu/api/publication/35218095}, author = {Ádám, B.Á. and Kis-Tót, B. and Jávor, B. and László, Szabolcs and Vezse, Panna and Huszthy, Péter and Tóth, Tünde and Golcs, Ádám}, doi = {10.3390/s24144529}, journal-iso = {SENSORS-BASEL}, journal = {SENSORS}, volume = {24}, unique-id = {35218095}, year = {2024}, eissn = {1424-8220}, orcid-numbers = {Huszthy, Péter/0000-0001-7305-3312} } @article{MTMT:35191503, title = {Good results from sensor data: Performance of machine learning algorithms for regression problems in chemical sensors}, url = {https://m2.mtmt.hu/api/publication/35191503}, author = {Höfler, Lajos}, doi = {10.1016/j.snb.2024.136528}, journal-iso = {SENSOR ACTUAT B CHEM}, journal = {SENSORS AND ACTUATORS B-CHEMICAL}, volume = {421}, unique-id = {35191503}, issn = {0925-4005}, abstract = {Accurately predicting unseen data, instead of mere memorization of training examples, is a critical goal of machine learning. This generalization is particularly important in the field of chemical sensors, where the ability to accurately predict the chemical properties or concentration levels of unknown samples is crucial. The paper presents a comprehensive yet accessible introduction to various machine learning concepts, highlighting the importance of model interpretability and generalization in ensuring reliable and accurate results in this context. Nonlinear sensor array data are utilized to introduce key concepts (e.g., bias-variance tradeoff) and techniques (linear models, partial least squares regression, support vector machines, k-nearest neighbors, decision trees, ensemble methods, automated machine learning, symbolic regression, and artificial neural networks), providing a solid foundation to make informed decisions when selecting machine learning techniques for sensor-specific regression applications. The results clearly indicate a number of conclusions. First, overparameterized deep feedforward neural networks show great accuracy and generalization when trained on a sufficiently large dataset. Second, symbolic regression models proved to be more accurate than deep feedforward neural networks and classical machine learning techniques on smaller datasets. Third, the performance of various machine learning models was dataset-dependent, showing the importance of comparative studies to determine the most suitable approach. It is clear that the optimal model cannot be known a priori. This paper aims to provide a starting point for investigations on the performance of different machine learning techniques in chemical sensor applications.}, keywords = {machine learning; chemometrics; Deep neural networks; Sensor array; Symbolic regression}, year = {2024}, eissn = {0925-4005}, orcid-numbers = {Höfler, Lajos/0000-0002-8050-5820} } @article{MTMT:35162822, title = {Fabrication of ZnO–Al2O3 inverse opals with atomic layer deposited Amorphous-Al2O3 for enhanced photocatalysis}, url = {https://m2.mtmt.hu/api/publication/35162822}, author = {Lemago, Hamsasew Hankebo and Khauli, Nour and Hessz, Dóra and Igricz, Tamás and Pál, Petra and Cserháti, Csaba and Baradács, Eszter and Parditka, Bence and Erdélyi, Zoltán and Szilágyi, Imre Miklós}, doi = {10.1016/j.mssp.2024.108733}, journal-iso = {MAT SCI SEMICON PROC}, journal = {MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING}, volume = {183}, unique-id = {35162822}, issn = {1369-8001}, year = {2024}, eissn = {1873-4081}, orcid-numbers = {Hessz, Dóra/0000-0003-3033-2762} } @article{MTMT:35161159, title = {Endocannabinoid and neuroplasticity-related changes as susceptibility factors in a rat model of posttraumatic stress disorder}, url = {https://m2.mtmt.hu/api/publication/35161159}, author = {Szente, László and Balla, Gyula and Varga, Zoltán Kristóf and Tóth, Blanka and Bíró, László and Balogh, Zoltán and Hill, M.N. and Tóth, Máté and Mikics, Éva and Aliczki, Manó}, doi = {10.1016/j.ynstr.2024.100662}, journal-iso = {NEUROBIOL STRESS}, journal = {NEUROBIOLOGY OF STRESS}, volume = {32}, unique-id = {35161159}, issn = {2352-2895}, abstract = {Traumatic experiences result in the development of posttraumatic stress disorder (PTSD) in 10–25% of exposed individuals. While human clinical studies suggest that susceptibility is potentially linked to endocannabinoid (eCB) signaling, neurobiological PTSD susceptibility factors are poorly understood. Employing a rat model of contextual conditioned fear, we characterized distinct resilient and susceptible subpopulations based on lasting generalized fear, a core symptom of PTSD. In these groups, we assessed i.) eCB levels by mass spectrometry and ii.) expression variations of eCB system- and iii.) neuroplasticity-related genes by real-time quantitative PCR in the circuitry relevant in trauma-induced changes. Furthermore, employing unsupervised and semi-supervised machine learning based statistical analytical models, we assessed iv.) gene expression patterns with the most robust predictive power regarding PTSD susceptibility. According to our findings, in our model, generalized fear responses occurred with sufficient variability to characterize distinct resilient and susceptible subpopulations. Resilient subjects showed elevated prelimbic and lower ventral hippocampal levels of eCB 2-arachidonoyl-glycerol (2-AG) compared to resilient and non-shocked control subjects. Ventral hippocampal 2-AG content positively correlated with the strength of fear generalization. Furthermore, susceptibility was associated with i.) prefrontal, hippocampal and amygdalar neuronal hypoactivity, ii.) marked decrease in the expression of genes of transcription factors modulating neuroplasticity and iii.) an altered expression pattern of eCB-related genes, including enzymes involved in eCB metabolism. Unsupervised and semi-supervised statistical approaches highlighted that hippocampal gene expression patterns possess strong predictive power regarding susceptibility. Taken together, the marked eCB and neuroplasticity changes in susceptible individuals associated with abnormal activity patterns in the fear circuitry possibly contribute to context coding deficits, resulting in generalized fear. © 2024}, keywords = {SUSCEPTIBILITY; Neuroplasticity; endocannabinoid; posttraumatic stress disorder; RESILIENCE; rat; Generalized fear}, year = {2024}, eissn = {2352-2895}, orcid-numbers = {Balla, Gyula/0009-0007-6449-0773; Balogh, Zoltán/0000-0002-1020-4694} } @article{MTMT:35159601, title = {Spectroscopic investigation of size-dependent CO2 binding on cationic copper clusters: analysis of the CO2 asymmetric stretch}, url = {https://m2.mtmt.hu/api/publication/35159601}, author = {Reider, A.M. and Szalay, Máté and Reichegger, J. and Barabás, Júlia and Schmidt, M. and Kappe, M. and Höltzl, Tibor and Scheier, P. and Lushchikova, O.V.}, doi = {10.1039/d4cp01797h}, journal-iso = {PHYS CHEM CHEM PHYS}, journal = {PHYSICAL CHEMISTRY CHEMICAL PHYSICS}, volume = {26}, unique-id = {35159601}, issn = {1463-9076}, abstract = {Photofragmentation spectroscopy, combined with quantum chemical computations, was employed to investigate the position of the asymmetric CO2 stretch in cold, He-tagged Cun[CO2]+ (n = 1-10) and Cun[CO2][H2O]+ (n = 1-7) complexes. A blue shift in the band position was observed compared to the free CO2 molecule for Cun[CO2]+ complexes. Furthermore, this shift was found to exhibit a notable dependence on cluster size, progressively redshifting with increasing cluster size. The computations revealed that the CO2 binding energy is the highest for Cu+ and continuously decreases with increasing cluster size. This dependency could be explained by highlighting the role of polarization in electronic structure, according to energy decomposition analysis. The introduction of water to this complex amplified the redshift of the asymmetric stretch, showing a similar dependency on the cluster size as observed for Cun[CO2]+ complexes. © 2024 The Royal Society of Chemistry.}, keywords = {COPPER; Carbon Dioxide; SPECTROSCOPIC ANALYSIS; Cluster Analysis; Electronic structure; Quantum chemistry; Copper compounds; binding energy; Blue shift; Quantum chemical computations; Spectroscopic investigations; size dependent; Cluster sizes; photofragmentation; Copper cluster; Cationics; Band position; Redshifting}, year = {2024}, eissn = {1463-9084}, pages = {20355-20364} } @article{MTMT:35159592, title = {Acetylene and Ethylene Adsorption during Floating Fe Catalyst Formation at the Onset of Carbon Nanotube Growth and the Effect of Sulfur Poisoning: a DFT Study}, url = {https://m2.mtmt.hu/api/publication/35159592}, author = {Orbán, Balázs and Höltzl, Tibor}, doi = {10.1021/acs.inorgchem.4c01830}, journal-iso = {INORG CHEM}, journal = {INORGANIC CHEMISTRY}, volume = {63}, unique-id = {35159592}, issn = {0020-1669}, abstract = {Here, we investigated the adsorption of acetylene and ethylene on iron clusters and nanoparticles, which is a crucial aspect in the nascent phase of carbon nanotube growth by floating catalyst chemical vapor deposition (FCCVD). The effect of sulfur on adsorption was also studied due to its indispensable role in the process and its commonly known impact on metal catalyst poisoning. We performed systematic density functional theory (DFT) computations, considering numerous adsorption configurations and iron particles of various sizes (Fen, n = 3-10, 13, 55). We found that acetylene binds significantly more strongly than ethylene and prefers different adsorption sites. The presence of sulfur decreased the adsorption strength only in the immediate proximity of the adsorbate, suggesting that the effect of sulfur is mainly of steric origin while electronic effects play only a minor role. Higher sulfur coverage of the catalyst surface significantly weakened the binding of acetylene or ethylene. To further investigate this interaction, Bader’s atoms in molecules (AIM) analysis and charge density difference (CDD) were used, which showed electron transfer from iron clusters or nanoparticles to the adsorbate molecules. The charge transfer exhibited a decreasing trend as sulfur coverage increased. These results can also contribute to the understanding of other iron-based catalytic processes involving hydrocarbons and sulfur, such as the Fischer-Tropsch synthesis. © 2024 The Authors. Published by American Chemical Society.}, keywords = {ARTICLE; MOLECULES; CATALYSIS; sulfur; sulfur; CARBON NANOTUBES; controlled study; IRON; IRON; NANOPARTICLES; Electron Transport; ADSORPTION; ADSORPTION; nanoparticle; CATALYST; ETHYLENE; ETHYLENE; ACETYLENE; ACETYLENE; Lighting; Particle size analysis; density functional theory; density functional theory; Chemical vapor deposition; Chemical vapor deposition; hydrocarbon; Catalyst poisoning; Charge transfer; carbon nanotube; peatland; Fischer-Tropsch synthesis; Charge density; Iron nanoparticles; carbon nanotube growth; Fe catalyst; Density functional theory studies; Ethylene adsorption; Sulphur poisoning; Acetylene adsorption; Catalysts formation; Iron cluster; Sulfur coverage; Fischer Tropsch synthesis}, year = {2024}, eissn = {1520-510X}, pages = {13624-13635} } @article{MTMT:35145824, title = {Revealing the ongoing speleogenetic processes in an underwater cave through the application of natural radionuclides and stable isotopes: case study from the hypogene Buda Thermal Karst}, url = {https://m2.mtmt.hu/api/publication/35145824}, author = {Erőss, Anita and Hegedűs-Csondor, Katalin and Kovács-Bodor, P and Szieberth, Dénes and Horváth, Á and Czuppon, György and Mindszenty, Andrea and Leél-Őssy, Szabolcs and Mádlné Szőnyi, Judit}, doi = {10.5038/1827-806X.53.2.2510}, journal-iso = {INT J SPELEOL}, journal = {INTERNATIONAL JOURNAL OF SPELEOLOGY}, volume = {53}, unique-id = {35145824}, issn = {0392-6672}, abstract = {The underwater Molnár János Cave in the hypogene Buda Thermal Karst system (Budapest, Hungary) provides a unique site to study the effects of flowing groundwater and the interplay of fluids of different origin. The aim of the present study is to characterize the groundwater in different parts of the cave with temporal resolution, hence describe the recent speleogenetic processes within the cave. This study uses natural radioisotopes (uranium, radium, and radon) besides stable isotope ratios of oxygen and hydrogen to identify the different fluid components. The results show that the majority of the cave is situated in the flow path of the intermediate flow system, discharging in the Boltív Spring. Thus, the dominant recent speleogenetic processes are connected to this lukewarm groundwater. In contrast to previous views, typical hypogene processes, such as mixing corrosion involving thermal waters, are restricted to a narrower area in the cave, to the contact zone of lukewarm waters and the warmer upper water layer around the largest partially air-filled chamber (Kessler Hall). The warmer water layer is the result of free convection. In the air-filled chambers condensation-corrosion might be active. However, its effect is limited to the largest room (Kessler Hall), as it is open to surface conditions. More active mixing corrosion probably occurs deeper, in the area of the Northeastern Margin Fault, which is indicated by the radon content in the Boltív Spring. Regarding the temporal processes, the main driving force can be linked to the water level fluctuations of the Danube, which regulates the discharge of the regional flow-related thermal water upwelling, thus affecting the mixing ratio of the lukewarm waters transported by the intermediate flow systems and the thermal waters, representing the regional flow path, including basinal components.}, year = {2024}, eissn = {1827-806X}, pages = {147-158}, orcid-numbers = {Erőss, Anita/0000-0002-2395-3934; Hegedűs-Csondor, Katalin/0000-0002-3368-9620; Czuppon, György/0000-0002-7231-6042; Mindszenty, Andrea/0000-0001-8927-3053; Leél-Őssy, Szabolcs/0000-0002-5548-129X; Mádlné Szőnyi, Judit/0000-0002-5628-4386} }