Search Results (103)

This study examines the influence of SO₂ and its hydrate H₂SO₃ on the free energies of the core autocatalytic cycle of the formose reaction. We find that SO₂ and H₂SO₃ readily condense with aldehyde and alcohol functional groups to form bisulfite analogs of formose proto-metabolites under modeled conditions. The bisulfite functional group can provide intramolecular catalytic enhancement in specific isomers towards aldol additions and the retroaldol step that regenerates two equivalents of glycolaldehyde from tetrose. The bisulfite moiety reduces the favorability of the parasitic Cannizzaro side-reaction both thermodynamically and kinetically, thus potentially furnishing more throughput towards forming sugars. As a prebiotic analog to phosphate, we find that bisulfite slightly stabilizes ribose over its C₅ aldose diastereomers thermodynamically, although the effect is modest and may be influenced by solution dynamics. Full article

Polystyrene (PS) is widely used yet highly flammable, and developing halogen-free flame retardants that ensure both high fire safety and mechanical performance remains a challenge. A green intumescent system comprising ammonium dihydrogen phosphate (ADP) and phytic acid–triethylenetetramine (PA–TETA) was incorporated into PS powder via sequential solution grinding and hot pressing. The optimal formulation, PS/10ADP/15PA–TETA, achieved a limiting oxygen index of 28.5% with a UL-94 V-0 rating, and reduced the peak heat release rate and total heat release by 73.8% and 46.2%, respectively, while retaining 78.4% of the tensile strength of neat PS. The ADP/PA–TETA system operates via a cooperative condensed-phase charring and gas-phase dilution mechanism, achieving superior flame retardancy in PS composites. This work provides an effective and eco-friendly strategy for fabricating high-performance PS composites with balanced flame retardancy and mechanical properties. Full article

This study presents a cradle-to-grave Life Cycle Assessment (LCA) and cost analysis of next-generation low-temperature district heating networks based on water-condensed electric booster heat pumps. The research, conducted within the ENEA Portici Research Center framework, evaluates multiple case studies to assess environmental and economic sustainability. The system boundaries include heat generators (geothermal heat pump, solar thermal, and photovoltaic–thermal hybrid), network configurations (tree vs. ring), supply temperatures (25 °C vs. 45 °C), and renewable electricity shares (0–100%). Environmental impacts were quantified using the Environmental Footprint 3.1 method, focusing on key indicators such as climate change, resource use, and human toxicity. The results show that supply temperature is a critical factor: 45 °C scenarios lead to notably higher impacts, while network configuration has only marginal effects. Among generation technologies, the photovoltaic–thermal system proved the most sustainable, despite higher investment costs, whereas the solar thermal system displayed the largest environmental burden but lower costs. Geothermal systems showed intermediate performance, with notable impacts from mineral resource use. Renewable electricity integration consistently improved environmental outcomes, reducing climate change impacts by up to 10%. Storage system comparison revealed lithium iron phosphate (LFP) batteries as the most advantageous solution for electrical storage, and phase-change materials (PCM), particularly Rubitherm15, as the most environmentally favorable option for thermal storage, although traditional water tanks remain more cost-effective. Overall, the study highlights the crucial role of renewable integration and temperature optimization in enhancing the eco-efficiency of low-temperature district heating networks, providing guidelines for future sustainable design and deployment. Full article

This article is devoted to the synthesis and investigation of a family of new benzimidazole compounds with a propylsulfonate moiety, synthesized by condensation of salicylic aldehyde or its 5-substituted derivatives with 3-(2,3-dimethylbenzimidazol-1-ium-1-yl)propane-1-sulfonate. The structure of the obtained dyes was confirmed using NMR, FT-IR, and HRMS. Absorption and photoluminescence properties were studied in phosphate buffers over a wide pH range, and changes in the absorption and fluorescence spectra of DMSO solutions upon titration with DIPEA and HCl were also studied. It was found that all the target compounds possess pH-sensitive optical properties and can be used as fluorescent probes, while methoxycarbonyl-substituted derivative 3c demonstrated the most prominent optical and fluorescent response starting from pH ~ 4.5. The toxicity of the compounds was studied using whole-cell bioluminescent bacterial sensors. The effect on the biomass and metabolic activity of strains Staphylococcus aureus ATCC 6538-P FDA 209-P and Escherichia CDC F-50 bacterial biofilms was also investigated. In the final stage of the study, bioimaging experiments were carried out using the selected most promising dye 3c and biofilms. It was demonstrated that the dye can be excited by light with wavelengths of 458 nm or 750 nm in multiphoton mode. Importantly, when biofilms are incubated in the dye solution for 3 h, only the extracellular matrix is stained. However, if the staining time is increased to 24 h, dye penetration into bacterial cells is observed, resulting in a second photoluminescence maximum during sample analysis. It is important to note that when biofilms are incubated in a dye solution for 3 h, only the extracellular matrix is stained, while with longer staining, penetration of the dye into bacterial cells is observed, and a second photoluminescence maximum appears during sample analysis. The results obtained demonstrate a high potential of using benzimidazole-based compounds as pH-sensitive fluorescent probes operating in a biologically relevant pH range, which can be used for imaging of bacterial biofilms. Full article

The reaction of imidazole-5-carbohydrazide 1 with hydrazonyl halides 2a,b gave the corresponding hydrazide–hydrazone derivatives 3a,b. Afterwards, 3-methyl-5-(4-methyl-2-aryl-1H-imidazol-5-yl)-4-(2-phenylhydrazineylidene)-4H-pyrazole 4a,b was affordably produced by cyclizing the latter compounds 3a,b in EtOH with Et₃N at reflux temperature. The corresponding piperidinyl, morpholinyl, and piperazinyl derivatives 5a–f were produced by a nucleophilic substitution reaction of 3a,b with piperidine, morpholine, and 1-methylpiperazine in EtOH at reflux temperature. The condensation reaction of carbohydrazide 1 with either 3-acetyl-2H-chromen-2-one or 1-(benzofuran-2-yl)ethan-1-one in EtOH with AcOH at reflux temperature yielded the corresponding hydrazones 6 and 7, respectively, in excellent yields. Twelve compounds were evaluated for their antibacterial properties and to ascertain their minimum inhibitory concentrations utilizing well diffusion methods. All compounds showed differing levels of antibacterial efficacy depending on the microbial species. Compounds 4b and 5c had the most favorable results, with inhibition zones of 2.7 cm against the Gram-positive bacterium S. aureus, with a minimum inhibitory concentration (MIC) of 50 µg/mL. Compounds 4b and 5c, demonstrating the highest activity, were subjected to molecular docking investigations to evaluate their inhibitory effects on the enzyme L-glutamine: D-fructose-6-phosphate amidotransferase [GlcN-6-P] of 2VF5. The molecular docking results revealed that both 4b and 5c exhibited a minimum binding energy of −8.7 kcal/mol, whereas the natural ligand GLP displayed a binding energy of −6.2 kcal/mol, indicating a substantial affinity for the active site; thus, they may be considered potent inhibitors of GlcN-6-P synthase. Full article

Pharmacological chaperones of heterogeneous nuclear ribonucleoproteins (hnRNPs) show promise as potential neuroprotective drug candidates. They are expected to prevent the accumulation of neurotoxic hnRNP biocondensates and aggregates, which are hallmarks of severe degenerative diseases. Here, we present the first rational design of oligonucleotide chaperones of hnRNP A1. This design was inspired by previous studies on the specificity of the RNA recognition motif (RRM) and the RGG motif of hnRNP A1 for endogenous nucleic acids. To obtain robust and specific chaperones, we combined an RRM-binding sequence with an RGG-binding G-quadruplex oligonucleotide that inhibits hnRNP A1 aggregation and introduced various modifications into the sugar-phosphate backbone of the oligonucleotide. Modifications that locked the RRM-binding sequence in a conformational state characteristic of RNA improved chaperone affinity and activity. The former was assessed using microscale thermophoresis assays, while the latter was evaluated using fluorimetry and microscopy. The leading chaperone bound to hnRNP A1 at micromolar concentrations and inhibited the assembly of its condensates and amyloid-like aggregates (fibrils) by over 90%. Full article

Adenosine nucleotides and polyphosphates play a significant role in biochemistry, from participating in the formation of genetic material to serving as metabolic energy currency. In this study, we examine the stability and decomposition rates of adenosine phosphates—5′-AMP, 5′-ADP, and 5′-ATP (mentioned simply as AMP, ADP and ATP hereafter)—at temperatures of 22–25 °C, 50–55 °C, 70–75 °C, and 85–90 °C, at a pH of 4, over periods of 2 and 4 days, in both saltwater and ultrapure water, under unsealed and completely dried down conditions. We found that adenosine phosphates degrade rapidly under heat and dehydration, particularly at temperatures above 25 °C. Among the three compounds, AMP is the most stable, maintaining its integrity between 22 and 55 °C, whereas ATP begins to degrade at 22–25 °C and ADP is completely decomposed at temperatures above this range. Decomposition rates were analyzed using quantitative ³¹P-NMR, based on the detection of various phosphorus-containing species. AMP primarily hydrolyzed into phosphate, pyrophosphate and even formed 2′,3′-cAMP. In contrast, the condensed adenosine phosphates (ADP and ATP) hydrolyzed to AMP, phosphate, pyrophosphate, triphosphate, 5′-AMP and, in some cases, 2′,3′-cyclic adenosine monophosphate (2′,3′-cAMP). We also investigated the formation of these compounds in the presence of N-containing additives such as thiourea, urea, imidazole, and cyanamide at temperatures between 65 and 70 °C. Among these, cyanamide and urea were particularly effective in promoting the synthesis of adenosine monophosphates (AMPs) from phosphate and adenosine. The major products observed were 2′,3′,5′-AMPs and cyclic 2′,3′-AMPs. In some experiments, adenosine diphosphate (ADP) and dimeric nucleotide species were also detected. These findings suggest that moderately heated evaporating pools could facilitate the abiotic formation of AMPs. However, such environments would likely have been unsuitable for the long-term accumulation of these compounds due to continued degradation, though there would exist some level of these nucleotides at steady state. Full article

Solketal is an important chemical product with widespread applications, and the raw materials glycerol and acetone are inexpensive, making it highly economically viable. The glycerol-acetone condensation reaction is a typical acid-catalyzed reaction. Traditional homogeneous acidic catalysts cause significant environmental pollution and are difficult to recover. Herein, PEG-800 was used as an additive, and a one-pot process was employed to prepare a series of aluminum phosphate catalysts (xP-Al-O) with different P/Al molar ratios. The physical and chemical properties of the prepared xP-Al-O catalysts were thoroughly investigated using XRD, FTIR, SEM, Py-FTIR, BET, and NH₃ (CO₂)-TPD methods. The results indicated that different P/Al molar ratios indeed affect the catalyst structure, and all prepared xP-Al-O samples exist in the form of amorphous aluminum phosphate, with weak acidic sites dominating the surface. The prepared catalysts were investigated for their catalytic behavior in the acetalization reaction of glycerol and acetone. The 1.1P-Al-O catalyst exhibited the highest acetone glycerol acetal yield and demonstrated good catalytic stability. Full article

The flammability and volatility of conventional lithium hexafluorophosphate (LiPF₆)-based electrolytes with organic carbonate solvents remain critical issues to the safety and thermal stability of lithium-ion batteries (LIBs). This study investigates the incorporation of phosphate-based additives including ammonium dihydrogen phosphate (ADP), trimethyl phosphate (TMP), and trimethyl phosphite (TMPi) into LiPF₆ electrolytes for improving the ionic conductivity, safety, and electrochemical performance of LIBs. Self-extinguishing time (SET) measurements demonstrated that the ADP-based LiPF₆ electrolyte significantly reduced flammability, achieving a shorter SET of 04 min 53 s, compared to 12 min for the pristine LiPF₆ electrolyte. The ADP-based LiPF₆ electrolyte possessed the highest ionic conductivity (14.08 mS·cm⁻¹) with an excellent lithium-ion transference number of 0.0076. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (C-V) analyses demonstrated that ADP lowered interfacial resistance and stabilized long-term cycling behavior. In particular, the 1% ADP-based LiPF₆ electrolyte maintained improved charge-discharge profiles and Coulombic efficiency over 200 cycles. These results highlight ADP’s dual functionality in suppressing gas-phase flammability and enhancing condensed-phase electrochemical stability, making it a promising candidate for next-generation, high-safety, high-performance LIB electrolytes. Full article

To satisfy the superior surface quality requirements in the fabrication of HBM (High-Bandwidth Memory) and 3D NAND Flash Memory, high-efficiency Si chemical mechanical planarization (CMP) is essential. In this study, a colloidal silica abrasive-based Si-wafer CMP slurry was developed to simultaneously achieve a high polishing rate (≥10 nm/min) and low surface roughness (≤0.2 nm) without inducing CMP-induced scratches. The proposed Si-wafer CMP slurry incorporates two functional components: triammonium phosphate (TAP) as a hydrolysis reaction accelerator and hydroxyethyl cellulose (HEC) as an abrasive drag force accelerator. The polishing rate enhancement mechanism of TAP was analyzed by monitoring the OH⁻ mol concentration, surface adsorption behavior, and XPS spectra. The results showed that increasing the TAP concentration raised the OH⁻ mol concentration and converted Si–Si and Si–O–Si bonds to Si–OH via a hydrolysis reaction, thereby increasing the polishing rate. However, excessive hydrolysis also led to increased surface roughness. On the other hand, HEC influenced slurry viscosity, abrasive dispersibility, and drag force. At low HEC concentrations, increased abrasive drag force improved the polishing rate. At high concentrations, however, HEC formed a hindrance layer on the Si surface via hydrogen bonding and condensation reactions, reducing the effective contact area of abrasives and thus decreasing the polishing rate. By optimizing the concentrations of TAP (0.0037 wt%) and HEC (≤0.0024 wt%), the proposed slurry formulation achieved high-performance Si-wafer CMP, satisfying both surface roughness and polishing rate targets required for advanced memory packaging applications. Full article

Oxidative and inflammatory stresses contribute to the development of many intestinal pathologies. This study characterized the polyphenolic profile and biological activity of a hydroalcoholic extract obtained from the fruit pulp of Feijoa sellowiana on HT29 intestinal epithelial cells subjected to oxidative (H₂O₂) and inflammatory (cytokines) stress. HPLC-DAD-MS analysis revealed an interesting phenolic composition, rich in hydrolyzable tannins (HHDP-glucose, pedunculagin and other ellagic acid derivatives) and condensed tannins (procyanidin dimers), with a total polyphenol content of 8.07 mg/g GAE. The extract was non-cytotoxic up to 160 µg/mL and exerted a protective effect against the cytokine-induced reduction in cell viability. In vitro assays confirmed its strong antioxidant and scavenging capacity. The scratch assay suggested enhanced cell migration. The extract modulated the activity of key metabolic enzymes restoring glucose-6-phosphate dehydrogenase and enolase activity, while supporting glycolytic flux through pyruvate kinase and lactate dehydrogenase. PCA and Pearson correlation analyses confirmed a treatment-dependent modulation of the metabolic and redox profile, suggesting a regulatory role beyond a mere scavenging effect. These findings highlight the nutraceutical potential of feijoa polyphenols, not only as direct antioxidants but also as modulators of cellular metabolism and redox homeostasis, supporting their application in gastrointestinal disorders with oxidative or inflammatory components. Full article

The dynamic phosphorylation of the human RNA Pol II CTD establishes a code applicable to all eukaryotic transcription processes. However, the ability of these specific post-translational modifications to convey molecular signals through structural changes remains unclear. We previously explained that each gene can be modeled as a combination of n circuits connected in parallel. RNA Pol II accesses these circuits and, through a series of pulses, matches the resonance frequency of the DNA qubits, enabling it to extract genetic information and quantum teleport it. Negatively charged phosphates react under RNA Pol II catalysis, which increases the electron density on the deoxyribose acceptor carbon (2’C in the DNA sugar backbone). The phosphorylation effect on the stability of a carbon radical connects tyrosine to the nitrogenous base, while the subsequent pulses link the protein to molecular water through hydrogen bonds. The selective activation of inert C(sp³)–H bonds begins by reading the quantum information stored in the nitrogenous bases. The coupling of hydrogen proton transfer with electron transfer in water generates a supercurrent, which is explained by the correlation of pairs of the same type of fermions exchanging a boson. All these changes lead to the formation of a molecular protein–DNA–water transcriptional condensate. Full article

Enzyme catalysis represents a promising approach for sustainable chemical synthesis, yet its industrial applications face limitations due to the inefficient regeneration and high cost of essential cofactors, such as adenosine-5′-triphosphate (ATP) and nicotinamide adenine dinucleotide phosphate (NADPH). While natural metabolic systems efficiently recycle cofactors through spatially organized enzymes, replicating this efficiency in vitro remains challenging. Here, we prepare a five-enzyme condensate system using liquid–liquid phase separation (LLPS) mediated by intrinsically disordered proteins (IDPs). By colocalizing a carboxylic acid reductase from Norcadia iowensis (NiCAR) with a reductive aminase from Aspergillus oryzae (AspRedAm) and three cofactor-regenerating enzymes, we generated a phase-separated catalytic condensate that enhanced ATP and NADPH recycling efficiency by 4.7-fold and 1.9-fold relative to free enzymes, respectively. Catalytic performance was correlated with the extent of phase separation, as confirmed by fluorescence microscopy, which revealed clear enrichment of ATP and NADPH within the condensates. This proximity effect enabled efficient cofactor turnover in the one-step reaction, achieving substrate conversion above 90% within 6 h and enhancing the space–time yield (STY) of the chiral imines 1.6-fold, with only one-fifth of the standard cofactor load. This approach creates a scalable and economic tool for performing multienzyme cascade reactions in vitro that are driven by the efficient recycling of multiple cofactors. Full article

2,5-furandicarboxaldehyde (DFF) is one of the most promising biomass-based building blocks for the synthesis of biobased polymers. DFF can be obtained from 5-hydroxymethylfurfural (HMF), a fructose derivate, and it is a key molecule in the sequence of reactions of furan chemistry to develop biobased plastics. In this frame, four manganese(III)–Schiff base complexes 1–4 have been obtained. The general formula for the complexes, MnLⁿ(OCN)(H₂O/CH₃OH)_m (Lⁿ being the Schiff base ligands L¹–L⁴, formed as the result of the condensation of different substituted hydroxybenzaldehydes with diverse diamines, and m = 1–3), has been confirmed by characterization through different analytical and spectroscopic techniques. X-ray crystallographic studies for 1 and 2 showed tetragonally distorted octahedral structures, where the Schiff base was placed in the equatorial coordination positions of the Mn(III) ion. Complexes 1 and 2 behaved as efficient catalysts in the oxidation of HMF to DFF in an electrolytic reaction at pH 8.5, with phosphate buffer at room temperature, with conversion rates of 70–80%. On the other hand, complexes 3 and 4, where the axial position was sterically less accessible, yielded only an 11% conversion of HMF to DFF. The results indicate that a correct selection of metal complexes allows the development of a new efficient way to obtain DFF. Full article

Monolayer nanosheets of zirconium phosphate in aqueous suspension exhibit short-range repulsion and long-range attraction, producing, at overall volume fractions larger than about half a percent, phase separation into higher-concentration liquid crystal and lower-concentration isotropic regions. At high concentrations, this phase separation takes the form of an emulsion of condensed, liquid-crystalline droplets, which anneal to form lens-shaped tactoids. These tactoids provide an opportunity to study the liquid crystal ordering of inorganic nanosheets in the limit of large shape anisotropy (diameter/thickness~400) and high packing fraction (volume fraction $\gtrsim$ 70%). The internal liquid crystal structure of the tactoids remains nematic even under conditions that would usually favor ordering into lamellar smectics. Local lamellar ordering is suggested by short-range, smectic-like layer correlations, but a full transition into a smectic phase appears to be inhibited by the nanosheet edges, which act as a perturbative population of dislocation loops in the system of layers. Under conditions of thermal equilibrium, the nanoplates organize positionally to enable bend deformation of the director, a hallmark of the nematic phase and its principal distinction from the smectic, where bend must be expelled. Full article