Chemistry and Materials Science

Abstract: Efficient pretreatment is essential for improving the conversion of lignocellulose into fermentable sugars and bioethanol. In this study, choline chloride–monoethanolamine (ChCl-MEA)-based ternary deep eutectic solvents containing H₂O₂, NaHCO₃, Na₂S, or ethylene glycol were prepared and applied to pretreatment of Dendrocalamus brandisii. Among the tested systems, ChCl-MEA-Na₂S showed the best overall pretreatment performance, achieving 92.8% delignification and 86.1% cellulose retention. It also effectively disrupted lignin–carbohydrate associations, reduced lignin shielding and generated a more accessible cellulose-rich substrate for bioconversion. In the following separation enzymatic hydrolysis and fermentation, 92.2% cellulose in substrate was conversed to glucose and 17.49 g/L ethanol was obtained via the fermentation of enzymatic hydrolysate. Taking the bioconversion of substrate into consideration, the ChCl-MEA-H₂O₂ and ChCl-MEA-Na₂S were recovered for full components utilization. Especially, the carbon dots produced from the degradation compounds in ChCl-MEA-H₂O₂ DESs had favorable antioxidation and antibacterial performance due to the oxygen-containing group caused by oxidation of H₂O₂.

Abstract: Computer-aided drug design (CADD) is undergoing a fundamental paradigm shift driven by the transition from classical biophysical methods to deep learning architectures and generative artificial intelligence. This review analyzes the evolution of molecular docking algorithms. We examine traditional programs (AutoDock Vina, Glide, GOLD) based on stochastic conformational search and empirical scoring functions, which retain the status of gold standard due to the high physical validity of the generated predictions. Software solutions for high-throughput virtual screening, such as distributed pipelines like EasyDock and graphical interfaces like EasyDockVina, are analyzed. Particular attention is paid to the latest generative AI models (DiffDock, GNINA, AlphaFold 3, DynamicBind, FABFlex), which address the computational challenges of blind docking and macromolecular receptor flexibility. We assess the systemic crisis of neural network generalization ability identified in independent benchmarks (PoseBusters, Bento, NextTopDocker) and substantiate the need to integrate the laws of molecular physics into the latent spaces of models. We conclude that the formation of hybrid pipelines, combining the speed of AI with the rigor of classical mechanics, is a necessary development.

Abstract: Porous titanium materials exhibit tremendous potential in the field of photocatalytic dye degradation owing to their unique structural and performance advantages. Although traditional powder materials (such as TiO2 nanoparticles) possess high specific surface area and active sites, they suffer from issues of difficult recovery and low light utilization efficiency . Coating materials address the recovery problem by immobilizing the catalyst; however, their limitations including limited specific surface area, insufficient visible light response, and poor mechanical stability restrict their practical applications. In contrast, bulk materials with in-situ grown nano-sized titanium dioxide on the surface of a titanium core combine high specific surface area, enhanced visible light absorption capacity, and excellent mechanical stability, making them an ideal choice for photocatalytic dye degradation. In this study, nickel-doped porous titanium was used as the substrate, and Nix-TiO2 nanotube films with a three-dimensional (3D) network structure were successfully prepared via an in-situ hydrothermal method. The effects of nickel content (2.5 wt.%, 5 wt.%, 7.5 wt.%, 10 wt.%) and calcination temperature (350 ℃-750 ℃) on the structure, morphology, and photocatalytic performance of the composite materials were systematically investigated. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption-desorption (BET) techniques were employed to characterize the phase composition, micromorphology, chemical state, and specific surface area of the samples. Methylene blue (MB, 20 mg/L) was selected as the target pollutant to evaluate the photocatalytic activity and stability of the catalysts under simulated sunlight. Results indicated that nickel did not enter the TiO2 lattice but formed nickel oxide (NiO), constructing a semiconductor composite structure. Among all samples, the Ni7.5-TiO2 catalyst exhibited the optimal photocatalytic performance, achieving a 98.35% MB degradation rate within 3 hours and maintaining excellent cyclic stability after 5 consecutive degradation cycles. The optimal calcination temperature was determined to be 450 ℃, at which TiO2 nanotubes were completely in the anatase phase with an intact 3D network structure and high crystallinity. Compared with pure titanium substrates, the porous titanium-based catalyst showed a significant enhancement in adsorption capacity, and nickel doping further improved this performance by increasing the specific surface area and providing more active sites. The synergistic effect of nickel doping and the porous titanium-based nanotube structure effectively narrowed the TiO2 band gap, inhibited the recombination of photogenerated carriers, and improved solar energy utilization efficiency. This study provides a feasible technical approach for the treatment of wastewater containing organic pollutants and enriches the research on modified TiO2 photocatalytic materials.

Abstract: Due to the increasing threat of antibiotic resistance and the emergence of new pathogenic strains, the development of effective combined therapeutic agents represents a crucial direction in the fight against infections. Within this study, several compounds were synthesized in which iodine is present in a coordination complex with antibiotics – sodium sulfathimidine and gentamicin sulfate. The physicochemical parameters of these compounds were investigated using capillary electrophoresis and UV-spectroscopy, along with their cytotoxicity, antimicrobial, and antiviral activities. As a result of this work, two stable compounds, KC-246 and KC-248, were synthesized, demonstrating virus-inhibitory activity against herpes simplex virus and influenza A under extremely low cytotoxicity levels of 0.018–0.106 mg/ml. Additionally, they exhibited antimicrobial activity against representatives of the families Staphylococcaceae, Pseudomonadaceae, Enterobacteriaceae, Enterococcaceae, and yeast-like fungi. The minimum bactericidal concentrations (MBCs) ranged from 0.794 µg/ml to 0.198 µg/ml (KC-246) and from 2.093 µg/ml to 0.523 µg/ml (KC-248).

Abstract: Interest in non-centrosymmetric crystalline materials exhibiting second harmonic genera-tion (SHG) has increased due to their potential applications in optical sensing and bio-sensing. Saccharide-based metal complexes are particularly attractive systems, as chiral sugars can promote non-centrosymmetric crystal packing. In this work, a new lantha-num–β-D-fructose compound, [La(C₆H₁₂O₆)(H₂O)₅]Cl₃ (LaFRUCl), was synthesized by a simple and low-cost method and characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group P2₁2₁2₁ and consists of infinite (La³⁺–fructose)ₙ chains extending along the [001] direction, forming a one-dimensional metal–organic framework. The nonlinear optical response was evaluated using the Kurtz–Perry powder technique with a Nd:YAG laser (1064 nm) and compared to a sucrose ref-erence. The measured SHG efficiency is comparable to that of previously reported alkaline earth metal–sugar analogues. While the SHG emission is significant, evaluation of the compound’s structural stability under aqueous or physiological conditions would be re-quired before considering biological applications.

Abstract: Background: Research on green-synthesized nanomaterials (GSNs) for environmental remediation is growing rapidly, yet data remains fragmented in non-interoperable formats. Methods: We present OntoNanoMat, a comprehensive semantic resource consisting of a modular OWL 2 DL ontology and a curated dataset of case studies. The data was structured into five thematic modules: Identification, Synthesis, Mechanism, Performance, and Provenance. Results: The dataset is provided in three interoperable formats: CSV for tabular analysis, JSON for web applications, and Turtle (RDF) for Semantic Web integration. Technical validation was performed using SHACL shapes and SPARQL query libraries to ensure logical consistency and data integrity. Conclusions: OntoNanoMat provides a FAIR-compliant (Findable, Accessible, Interoperable, and Reusable) foundation for future machine learning applications and knowledge graph integration in sustainable nanotechnology.

Abstract: Background/Objectives: Cocrystallisation is a well-established path for altering the physicochemical properties and bioavailability of active pharmaceutical ingredients (APIs). A common side effect of anti-tubercular medicines is depletion of group B vitamin reserves in TB patients. Co-administration of supplements such as pyridoxine (vitamin B6) during TB therapy may be used to ameliorate the harmful side effects of vitamin B6 deficiency. Methods: Mechanochemical grinding and solvent evaporation experiments using pyridoxine (PN) with 4-aminosalicylic acid (PAS) and separately with pyrazinecarboxylic acid (PCBA) were conducted. The bulk powder and crystal analysis was performed using FTIR, PXRD, DSC, TGA and SCXRD . Results: The isolation and characterization of two multicomponent salts containing pyridoxine, i.e., PN-PAS‧H2O and PN-PCBA. Mechanochemistry is an efficient method for the preparation of cocrystals. Conclusions: The drug-vitamin combinations may be useful for the development of new treatment regimens with improved therapeutic outcomes and reduced adverse effects.

Abstract:

Nickel-supported over SiO₂-CeO₂ mixed oxides were investigated as catalysts for syngas production via the dry reforming of methane. The SiO₂-CeO₂ supports were optimized, playing on the preparation method and ceria loading with the aim of stabilizing nickel nanoparticles, enhancing the catalytic performance, and improving the resistance to coke formation under high-temperature reforming conditions. To investigate the effect of support composition, SiO₂-CeO₂ mixed oxides with ceria contents ranging from 5 to 30 wt% were prepared using two synthesis routes: sol-gel and wetness impregnation methods. A nickel loading of 5 wt% was deposited on the resulting supports. The catalysts were characterized by XRD, N₂ physisorption, temperature-programmed reduction, and Raman spectroscopy. Catalytic activity tests were conducted over reduced catalysts in an H₂-He stream at 750 °C, using a feed mixture containing 15 vol% CH₄ and 15 vol% CO₂ in He. The effect of temperature on catalytic performance was evaluated in the range of 450–800 °C. Thermogravimetric, XRD and Raman analyses of spent catalysts were used to assess carbon deposition and the nature of crystalline phases. The results highlight the role of CeO₂ content and preparation method in determining nickel dispersion, reducibility, catalytic performance in DRM, and coke resistance.

Abstract: We report the crystallization and single-crystal X-ray analysis of the monohydrate hy-drochloride salt of chloroquine, designed CQCl·H2O, an antimalarial drug (CQ) with the formula C₁₈H₂₆ClN₃. The crystal structure reveals a well-defined supramolecular architecture stabilized by an extensive hydrogen-bonding network involving CQH⁺ cations, chloride anions, and water molecules. Notably, this study provides the first crystallographic characterization of a monoprotonated chloroquine salt. Additionally, our findings demonstrate the feasibility of isolating pseudo-polymorphic forms of a commercially available CQ salt via heterogeneous crystallization.

Abstract: The first hydrogenation behavior of the gas atomized Ti48.8Fe46.0Mn5.2 alloy was system-ically investigated. The as-received powder showed no hydrogen absorption due to the long air exposure before the hydrogenation tests. To overcome this, 5 passes of cold rolling were employed as an activation strategy. Cold rolling introduced cracks and defects that facilitated hydrogen diffusion, enabling the alloy to successfully absorb hydrogen. The influences of temperature, constant driving force, and hydrogen pressure on the first hydrogenation were evaluated. The results indicated that the first hydro-genation follows an Arrhenius behavior, with calculated activation energies of 69 and 57 kJ/mol H2. The observed difference in activation energies is likely associated with the variation of the driving force under constant pressure conditions. The pre-exponential factor (A) was found to be pressure-dependent, following the equation A = A₀ (P/P₀)1.8, where A₀ = 1.3 × 106 s⁻¹.

Abstract: The critical micelle concentration (CMC) is a fundamental physicochemical property of surfactants with significant implications across multiple industries. This paper presents uncertainty-aware graph neural network that integrates molecular structure and temperature to simultaneously predict CMC values and prediction uncertainties. Trained on a curated dataset of 1,829 surfactants with temperature annotations, our GNN achieves competitive performance (RMSE = 0.352, MAE = 0.244) on an external test set, outperforming previous models in RMSE. The model provides statistically sound, adequately calibrated uncertainty estimates that reliably quantify prediction confidence. This dual-output approach enables reliable CMC prediction with quantifiable confidence intervals, addressing a practical need for safety-critical applications where underestimation of uncertainty could have serious consequences.

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The mechanism of catalytic low-temperature (T≤150 °C) oxidation of CO on Pd/Al₂O₃ was studied using labeled oxygen and thermal desorption analysis. It was found that the reaction proceeds through interaction in intermediate complexes of CO molecules with hydroxyl groups of Al₂O₃. A combined reaction mechanism through the formation and decomposition of carboxyl-type structures was proposed, in which adsorbed oxygen reoxidizes reduced palladium atoms and ensures the decomposition of carboxyl structures with the formation of CO₂ and the regeneration of OH groups. It was shown that with a small addition of Pd (0.04-0.1 wt.%) the activity of the catalyst increases significantly. The positive effect is due to the activation of CO or a change in the state of oxygen on the surface of the catalyst.

Abstract:

Efficient and localized singlet oxygen (SO) generation is essential for improving antimicrobial photodynamic therapy (aPDT). In this study, a bis-imidazolium-based amphiphilic gelator is used that self-assembles into a supramolecular gel in a water–ethanol medium and incorporates Rose Bengal (RB) as a photosensitizer. The gel network provides a confined environment that promotes SO formation under light irradiation. RB@Gel was characterized with respect to its morphology, degradation behavior, and swelling properties. Biopharmaceutical assessment included in-vitro release, ex-vivo permeation studies and Hen’s Egg Test–Chorioallantoic Membrane (HET-CAM) assay. Rheological measurements confirmed a viscoelastic profile, indicating structural stability and suitability for localized therapeutic applications. SO production within the gel was quantified using tetrasodium 9,10-anthracenediyl-bis(methylene)dimalonate (NaABMA), showing higher efficiency than that of RB in solution. The RB@Gel exhibited significant aPDT against E. coli in a direct-surface contact assay. Overall, the RB@Gel provides a stable, suitable platform capable of efficient SO generation and potent antibacterial activity, highlighting its promise for localized aPDT applications.

Abstract: Obesity and Type 2 diabetes mellitus (T2DM) are becoming major health concerns worldwide, with 890 million people being obese as of 2022 [1]. Recently developed drugs to treat T2DM have shown remarkable results in weight loss, proving them-selves as efficient tools in fighting obesity. They are also called GLP-1 agonists, because they mimic the action of the natural glucagon-like peptide-1 a hormone that regulates blood sugar by stimulating insulin secretion. However, these medications are extreme-ly expensive, so recent studies are focusing on finding natural alternatives that could be more affordable. In silico studies are computer simulations on how molecules inter-act, and may save a lot of experimental work by giving indications on which com-pounds could be effective for a given purpose. The present study carried out molecular docking on selected phytochemicals with reported roles in weight management and their interactions with GLP-1 receptors, as well as gastric inhibitory polypeptide re-ceptors (GIPR) and Dipeptidyl Peptidase-4 (DPP4). The selected molecules were: ber-berine, chlorogenic acid, curcumin, epigallocatechin gallate (EGCG), hesperidin, quer-cetin and rutin. The molecular docking results show that EGCG, hesperidin and rutin may have some good affinity with the GLP-1 receptor, berberine, hesperidin and rutin to DPP4, while none of the selected molecules had significant affinity to the GIP re-ceptor. However, these phytochemicals have much smaller molecules than the syn-thetic peptides that are used in the treatment of T2DM and obesity, so they may well bind to other receptors too and have little selectivity and specificity. The ADME profile indicates berberine as the most promising candidate for drug development. Further studies are needed to investigate if these molecules have practical application in the treatment of obesity and how they could be used.

Abstract: A series of azido- and cyclooctyne-functionalized N-hydroxysuccinimidyl esters (NHS esters) and benzotriazolides were prepared and used as N-acylation reagents to obtain azido- (BSA-1) and cyclooctyne-functionalized bovine serum albumin proteins (BSA-2), fluorescein derivatives 5 and 6, and homobifunctional linkers 3 and 4. Strain-promoted azide-alkyne cycloaddition (SPAAC) and copper-catalyzed azide-alkyne cycloaddition (CuAAC) of azido- functionalized fluorescent probe 5 and alkyne- functionalized fluorescent probe 6 with complementary functionalized proteins BSA-2 and BSA-1 yielded fluorescent cycloadducts BSA-2-5 and BSA-1-6. These cycloadducts were used to determine the loading of BSA-1 and BSA-2 with the respective azido and cyclooctyne groups based on their molar absorbances and fluorescence intensities. Dimerization through covalent cross-linking of BSA was then performed by SPAAC between azido-functionalized BSA-1 and cyclooctyne-functionalized BSA-2, and by treating BSA-1 and BSA-2 with 0.5 equiv. of com-plementary bis-cyclooctyne linker 4 and bis-azide linker 3. Although the formation of covalent dimers BSA-1-2-BSA, BSA-1-6-1-BSA, and BSA-2-5-2-BSA was detected by SDS-PAGE analysis, this was a minor process, and most of the functionalized BSA did not form covalent dimers.

Abstract: Due to its rich array of bioactive compounds, black pepper (Piper nigrum) is not only a spice in kitchens worldwide, but a plant of significant medicinal interest as well. Among these, piperine has wide-ranging biological effects and has become a focal point in scientific research. Besides piperine, black pepper also contains numerous other phytochemicals, like essential oils, flavonoids, terpenes, and lignans-all of which have shown pharmacological activities. This review offers an in-depth look at the various phytochemicals found in black pepper, detailing both traditional and modern techniques used for their extraction and purification. Particular attention is given to the total synthesis and chemical modifications of piperine and related compounds, outlining major developments and methodologies in this area. The review also briefly touches on the therapeutic applications validated so far. Overall, this work is intended to be a valuable resource for researchers interested in the chemical, synthetic, and medicinal potential of Piper nigrum.

Abstract:

In recent years, soil contamination with heavy metals—such as plumbum, cadmium, and cobalt—has become an increasingly pressing environmental issue due to the rapid expansion of industry, transportation, and urbanization. These elements are non-biodegradable, gradually accumulate along trophic chains, and can ultimately exert serious adverse effects on human health. In this study, we focused on sweet sorghum (Sorghum bicolor L.) as a promising candidate for phytoremediation of heavy metal–contaminated soils. Both field and laboratory approaches were employed: in vitro culture of somatic cells was used to select stress-tolerant and high-yielding genotypes, while atomic absorption spectroscopy (AAS) was applied to quantify heavy metal concentrations in soil and plant tissues. Experimental results demonstrated that callus induction frequency was strongly genotype-dependent. The highest callus formation rates were observed in Hybrid-2 (69.11%), SAB-3 (43.83%), SABB-1 (42.31%), and SAB-10 (40.32%). Among these, Hybrid-2 (27.94%) and SAB-3 (23.28%) also exhibited the highest frequencies of morphogenic callus formation, confirming their suitability for subsequent micropropagation and cell-based selection. Particular attention was paid to the distribution of toxicants among plant organs. The rate and direction of metal translocation from roots to shoots were found to critically influence the efficiency of subsequent metal removal, as stems constitute the major component of easily harvestable biomass. Nevertheless, a substantial proportion of heavy metals remained sequestered in the roots: cobalt concentrations reached 12.7 ± 1.32 mg/kg at 1 MPC (Maximum Permissible Concentration) and 16.87 ± 2.78 mg/kg at 2 MPC, accounting for more than 50% of the total accumulated amount. Similar trends were observed for cadmium (~49%) and plumbum (up to 53%). Thus, our findings underscore the pivotal role of genotype in in vitro callus formation and morphogenesis, and further highlight the potential of sweet sorghum as an effective phytoremediation agent for reclaiming heavy metal–contaminated lands, particularly in arid regions.

Abstract: Large language models (LLMs) are increasingly integrated into education, yet their ability to perform calculation-based tasks and generate scientific visualizations has been limited. This study evaluates Microsoft Copilot (GPT 5) for chemistry education across four domains: (1) chemical equilibrium, pH, titration, and buffer calculations; (2) data visualization using histograms, box plots, correlation plots, and heatmaps; (3) multivariate analysis of periodic table properties through principal component analy-sis (PCA); and (4) image interpretation and creation in classroom contexts. Thir-ty-three representative questions were tested without additional prompting. Copilot delivered accurate, step-by-step solutions for acid–base and equilibrium problems, generated high-quality visualizations directly from uploaded datasets, and produced PCA score and loading plots with proper data standardization. These results indicate that GPT 5 significantly improves over earlier LLM versions, offering a practical tool for enhancing conceptual understanding and data literacy in chemistry education. However, limitations persist in interpreting complex chemical imagery, requiring hu-man oversight. Future work should focus on refining multimodal accuracy and devel-oping pedagogical frameworks for responsible AI integration.

Abstract: The methanol oxidation reaction was investigated on Co- and/or Ag-based γ-Al2O3 catalysts, which were prepared by different methods and further doped with noble metals (Pd, Pt). During the present study, three different reaction pathways were revealed. Complete oxidation of methanol to CO2 and H2O was achieved over Pd-doped catalysts (Pd-Co/Al-SI and Pd-Ag/Al-SI), while partial oxidation to intermediates, such as formaldehyde, was observed for Ag/Al catalysts. The dehydration reaction of methanol to dimethyl ether took place over Co/Al, Ag-Co/Al and Pt-Co/Al catalysts. The 0.5wt.% Pd-5wt.% Co/γ-Al2O3 catalyst, prepared via the spray impregnation (SI) method, exhibited the highest methanol oxidation efficiency (T50: 43°C) and was further evaluated in the presence of H2O and CO in the feed, for several hours on stream. Initially, the activity of the catalyst was decreased, while over time complete oxidation of methanol was achieved. Characterization of the used catalyst revealed that in addition to the Co3O4 phase initially formed in the fresh catalyst, a CoO phase was also formed, concluding that the active phase of the 0.5Pd-5Co/Al-SI catalyst for the methanol oxidation reaction is a mixture of Co3O4 and CoO phases.

Abstract: Lipid metabolism is a vital biological process essential for human health, encompassing key pathways necessary for the survival and homeostasis of all organisms. Liver X Recep-tors (LXRs) are extensively acknowledged as pivotal regulators of lipid homeostasis and inflammatory responses. Pharmacological activation of liver X receptor (LXR) has been shown to increase expression of ApoE and ABCA1 reducing neurodegeneration in murine models of Alzheimer´s disease. Because previous reports determined that Nectandra reticu-lata (Lauraceae) extract has agonistic LXRs activity, the objective of this study was to de-termine the metabolites present in this extract and to evaluate their in silico and in vitro agonistic activity. Identification was done by reversed phase (RP) ultra-high performance liquid chromatography (UHPLC) with a diode array detector (DAD) and high resolution mass spectrometry with electrospray ionization (ESI-HR-MS). In silico study was performed by Auto Dock Vina. The in vitro agonist activity was evaluated using real-time re-verse transcription-polymerase chain reaction (qRT-PCR) to determine the RNA expression of ApoE and ABCA1. The chromatographic analysis revealed the presence of three glycosylated flavonols: The in silico study showed that isolated flavonoids generate a hydrogen bond with T302 and T316 (LXRα and LXRβ respectively). The in vitro study showed that the flavonoids increased the expression of mRNA of both APOE and ABCA1 target genes of LXRs, as observed by qRT-PCR. The bioactive flavonoids isolated in this study possess documented antioxidant effect, when combined with their LXR agonist activity, they become promising bioactive candidates for use in nutraceutical formulations aimed at promoting brain health and anti-inflammatory effects.