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The performance of Poly(lactic acid) (PLA) composites reinforced with functionalized titanium dioxide (TiO2) nanoparticles in rutile and anatase crystalline phases were systematically investigated. The results underline that the incorporation of TiO2, regardless of its crystalline structure, significantly enhances PLA's crystallinity by 85%. Notably, rutile TiO2, when functionalized with higher glutaric acid concentrations, was an effective crystallinity booster by 95%, passing from 20.39% to 39.58% crystallinity for the PLA/TiO2 R20 + 10% system. Furthermore, this research elucidates that the selection between anatase and rutile phases plays a vital role in the photostabilization. Functionalized Rutile TiO2 exhibited exceptional UV resistance, effectively inhibiting photodegradation; for example, after 15 days of exposure, the functionalized systems exhibited a 497.6% improvement for PLA/TiO2 R10 + 5% (22.1 ± 2.5 MPa), while the PLA/TiO2 R10 + 5% showed an 85.1% increase in composite stiffness (35.5 ± 3.5 MPa) after 7 days of degradation, in comparison with pristine PLA (19.2 ± 2.9 MPa). Anatase, conversely, displayed varying effects depending on concentration, acting as a stabilizer at lower levels and a promoter of degradation at higher concentrations. This knowledge enables the precise modifying of PLA composites for specific applications, balancing crystallinity, mechanical properties, and UV resistance for a diverse array of applications. Highlights: TiO2 enhances photostability in PLA confirming its potential as a UV stabilizer.Comparing anatase and rutile phase: Unveiling PLA composite dynamics.Glutaric acid on TiO2 enhances PLA composite strength significantly.Optimal acid concentration key to composite performance.Tailored PLA composites balance crystallinity, mechanics, and UV resistance. [ABSTRACT FROM AUTHOR]

The performance of Poly(lactic acid) (PLA) composites reinforced with functionalized titanium dioxide (TiO2) nanoparticles in rutile and anatase crystalline phases were systematically investigated. The results underline that the incorporation of TiO2, regardless of its crystalline structure, significantly enhances PLA's crystallinity by 85%. Notably, rutile TiO2, when functionalized with higher glutaric acid concentrations, was an effective crystallinity booster by 95%, passing from 20.39% to 39.58% crystallinity for the PLA/TiO2 R20 + 10% system. Furthermore, this research elucidates that the selection between anatase and rutile phases plays a vital role in the photostabilization. Functionalized Rutile TiO2 exhibited exceptional UV resistance, effectively inhibiting photodegradation; for example, after 15 days of exposure, the functionalized systems exhibited a 497.6% improvement for PLA/TiO2 R10 + 5% (22.1 ± 2.5 MPa), while the PLA/TiO2 R10 + 5% showed an 85.1% increase in composite stiffness (35.5 ± 3.5 MPa) after 7 days of degradation, in comparison with pristine PLA (19.2 ± 2.9 MPa). Anatase, conversely, displayed varying effects depending on concentration, acting as a stabilizer at lower levels and a promoter of degradation at higher concentrations. This knowledge enables the precise modifying of PLA composites for specific applications, balancing crystallinity, mechanical properties, and UV resistance for a diverse array of applications. Highlights: TiO2 enhances photostability in PLA confirming its potential as a UV stabilizer.Comparing anatase and rutile phase: Unveiling PLA composite dynamics.Glutaric acid on TiO2 enhances PLA composite strength significantly.Optimal acid concentration key to composite performance.Tailored PLA composites balance crystallinity, mechanics, and UV resistance. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) was crosslinked with a homologous series of four different dicarboxylic acids, HOOC(CH2) n‐2COOH (n = 2 to 5) viz. oxalic acid (OA; C2), malonic acid (MA; C3), succinic acid (SA; C4) and glutaric acid (GA; C5) containing odd and even number of carbon atoms. The characterization and assessment of synthesized crosslinked films were done using ATR‐FTIR, XRD, SEM, AFM, DSC, rheology, percent swelling and sessile drop contact angle. The odd‐even effect of dicarboxylic acids was observed to significantly influence the physicochemical properties of PVA when employed as a crosslinker. PVA films crosslinked using dicarboxylic acids containing an even number of carbon atoms, displayed translucency, roughness, and an irregular matrix. In contrast, films incorporating an odd number of carbon atoms were transparent, homogenous, and densely packed. Furthermore, films containing even acids exhibited relatively lower crystallinity, lower melting temperature (Tm) and displayed an unexpected irregular trend in swelling as crosslinker concentration increased compared to films containing dicarboxylic acids with an odd number of carbon atoms which exhibits a consistent swelling with increasing crosslinker concentration. These results are attributed to the difference in the solubility and crystal structures of the odd‐even series of dicarboxylic acids. [ABSTRACT FROM AUTHOR]

The present study demonstrates that low concentrations of azelaic acid (AZA) significantly impact the metabolism of Arabidopsis thaliana seedlings, leading to imbalances in numerous minerals and metabolites due to AZA‐induced stress. Untargeted metabolomic analyses were conducted on untreated and AZA‐treated seedlings at two time points: 7 and 14 days after treatment initiation. The results revealed a general accumulation of sugars (e.g., glucose, mannose, xylose), amino acids (e.g., lysine, GABA, threonine, glutamine), and organic acids (e.g., glutaric acid, shikimic acid, succinic acid) in AZA treated‐seedlings, suggesting that AZA triggers stress responses in Arabidopsis. Ionomic analysis revealed that AZA induces phosphorus deficiency, which plants compensate by increasing malate content in the roots. Additionally, AZA treatment induced putrescine accumulation within the root, a metabolic biomarker of potassium deficiency and plant stress. The metabolomic profile showed elevated levels of different specialized metabolites, such as nitrogen‐ and sulphur‐containing compounds, and altered levels of various phytohormones, including jasmonates and brassinosteroids, implicated in plant protection under biotic and/or abiotic stresses. These findings support the hypothesis that AZA's mode of action is associated with an auxin imbalance, suggesting its function as an auxinic herbicide. The observed increases in starch and jasmonates, coupled with the disruptions in potassium homeostasis, are linked to the previously reported alterations in the auxin transport, root architecture and gravitropic root response. Statistical analyses were applied, including Kruskal‐Wallis tests for ionomic data, as well as multifactor analysis, Principal Component Analysis, Orthogonal Partial Least Squares‐Discriminant Analysis, and enrichment pathway analysis for metabolomic data, ensuring the robustness and validity of these findings. [ABSTRACT FROM AUTHOR]

Abstract Glutaric aciduria type 1 (GA1) is an inherited neurometabolic disorder, in which deficiency of glutaryl‐CoA dehydrogenase leads to accumulation of glutaric acid (GA) and 3‐hydroxyglutaric acid (3‐HG). Some low excretors may exhibit only slight elevation of urinary 3‐HG, with normal urinary GA, yet are at significant risk of severe clinical disease. Accurate quantitation of urinary 3‐HG is crucial in diagnostic workup for GA1, but in this context, current gas chromatography–mass spectrometry (GC–MS) methods have inherent analytical challenges. Co‐elution and spectral similarities of the 3‐HG and 2‐HG structural isomers can cause difficulties in quantitation of slightly elevated 3‐HG. Our laboratory recently acquired a gas chromatography system coupled to a triple quadrupole mass spectrometer (GC–MS/MS), and we took advantage of its increased sensitivity and specificity to improve our existing GC–MS method. A stable isotope dilution process is used, with sample treatment consisting of a double liquid–liquid extraction followed by a trimethylsilyl derivatization. The transitions m/z 349 → 333 for 3‐HG and m/z 349 → 321 for 2‐HG were selected to differentiate these two isobaric molecules based on their characteristic fragments, thus minimizing interferences despite co‐elution. Method validation demonstrated satisfactory precision and accuracy. Using GC–MS/MS instead of GC–MS allowed us to decrease the required specimen volume, number of sample processing steps, chromatographic run time, and instrument maintenance. This enhanced assay facilitates clinical laboratory testing for GA1, both in confirmatory protocols following positive newborn screening and in diagnostic investigation of patients with suggestive signs or symptoms.

This work describes the comparison of the catalytic performances of α‐MnO2 nanorods synthesized by a facile hydrothermal approach at varying temperatures (140–200 °C). The structure and morphology of these nanorods were analyzed by XRD, N2‐physisorption, NH3‐TPD, Raman, SEM, HRTEM, and XPS. The prepared α‐MnO2 nanorods also performed exceptionally well in the catalytic oxidation of cyclohexanone to dicarboxylic acids under mild reaction conditions. The characterization results conferred that there is a significant influence of hydrothermal temperatures on the textural properties, morphology, and catalytic activity. Notably, the α‐MnO2 nanorods obtained from 180 °C hydrothermal conditions outperformed other catalysts with 77.3 % cyclohexanone conversion and 99 % selectivity towards acid products such as adipic acid (AA), glutaric acid (GA) and succinic acid (SA). The improved catalytic activity may be attributed to the interaction of the bifunctional Mn3+/4+ redox metal centres and surface acidic sites. The present oxidation reaction was found to be a promising eco‐benign process with high selectivity for the production of commercially significant carboxylic acids from cyclohexanone. [ABSTRACT FROM AUTHOR]

The presence of organics in Bayer liquors has a notable adverse effect on alumina production. Among these organics, dicarboxylic acids are a class of low molecular weight compounds that have yet to be studied for their decomposition in Bayer liquors using advanced oxidation techniques. This study aims to investigate the oxidation behavior of four dicarboxylic acids, including malonic acid (C3), succinic acid (C4), glutaric acid (C5), and adipic acid (C6), in Bayer liquors. The influences of different variables, such as sodium persulfate (SPS) dosage, initial organic concentration, caustic soda concentration, reaction temperature, and reaction time, on the advanced oxidation process of dicarboxylic acids were also studied. The results of the experiment indicate that an increase in SPS dosage, initial organic concentration, reaction temperature, and reaction time promoted the removal of total organic carbon (TOC). However, the concentration of caustic soda had an inhibitory effect on TOC removal, and it also affected the type of decomposition products of dicarboxylic acids. The EPR results revealed that the reactive groups responsible for organic decomposition were SO 4 - · and HO · . Dicarboxylic acids were found to produce several decomposition products, including carbon dioxide (in the form of carbonate), formic acid, and oxalic acid. Additionally, malonic and fumaric acids were observed as the main oxidation intermediates for dicarboxylic acids with C-atom numbers > 3. A reaction mechanism for succinic acid was also proposed. Advanced oxidation techniques have shown promise as a means of removing organics from Bayer liquors. [ABSTRACT FROM AUTHOR]

Oxidation of cyclopentanone (CPO) was studied over metal-free carbon catalysts in solvent-free conditions. Norit SX plus (900 m2 g−1) and Vulcan XC72 (240 m2 g−1) were used as pristine materials. Catalysts were prepared by activation in nitrogen and by treatment with urea, calcined in nitrogen at 500 °C and 950 °C. SEM, EDX, XPS, X-ray powder diffraction, nitrogen adsorption–desorption isotherms, acid–base titration, FTIR and Raman techniques were used for characterization. Catalytic tests carried out at 0.45 MPa and 80–110 °C enabled to find the best results: 30% selectivity to glutaric acid (GA) and 3% to succinic acid at 25% conversion of CPO, over Vulcan type catalysts. A low activity, selectivity and strong deactivation of Norit type catalysts can be ascribed to a higher specific surface in a disordered arrangement providing a high concentration of unselective catalytic sites. A higher extent of side reactions can yield in higher molar mass products, which stick on the surface and block catalytic sites. Optimum amount of accessible planar domains, represented by graphene and/or graphitic plates with some disorders present in Vulcan type catalysts classified them superior to Norit catalysts. A redox reaction scheme of oxidation of CPO to GA is also proposed. [ABSTRACT FROM AUTHOR]

A unique series of compounds was prepared from glutaric acid and various 2-amino thiazoles via a simple yet efficient synthetic method at ambient temperature. The N-(thiazol-2-yl)piperidine-2,6-dione derivatives were synthesized and characterized using multiple physicochemical techniques, X-ray crystallography, and SHG analysis. 2 out of the 5 newly synthesized compounds displayed strong nonlinear optical (NLO) properties. All five compounds were studied computationally, and UV spectroscopy was used to confirm the second harmonic generation (SHG) phenomenon. It was found that the compounds having a non-centrosymmetric space group have a larger band gap than the centrosymmetric space group and thus have more SHG properties. Compounds with large band gaps also have the distinctive S⋯O interaction, contributing significantly to conformational control of the crystal's geometry. [ABSTRACT FROM AUTHOR]

The present study investigates the influence of organic acids, added to the electrolytic solution, on the structure, morphology, and corrosion behaviour of plasma electrolytic oxidation (PEO) coatings produced on titanium grade 2. Particular attention is paid to the role of functional groups in the modification of the oxide's properties. For this reason, all three selected acids, namely glutaric, glutamic, and tartaric acid, display two carboxylic groups, thus they interact with the substrate material mainly through –COO− adsorption. However, glutamic acid also has an amine group, while tartaric acid has two hydroxyl groups. The presence of such additional functional groups is found to impact the formation of the PEO coatings. According to scanning electron microscopy (SEM) analyses, the number of defects and their dimension increase with an increasing number of active groups present in the organic molecules. Then, when glutaric acid with only two carboxyl groups, is employed as an additive, smaller pores are produced. The dimension of defects increases when glutamic and tartaric acid are used. X-ray diffraction (XRD) testing demonstrates that rutile and anatase are present in all the coatings and that when using tartaric acid, a relatively high level of amorphism is reached. The electrochemical and corrosion behaviours are evaluated by potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) performed in a heated sulphuric acid solution. It is found that all types of coatings provide protection against corrosion, with oxides produced using glutamic acid showing the lowest corrosion current density (0.58 mA·m−2) and low corrosion rate (1.02 μm·y−1). [ABSTRACT FROM AUTHOR]

We examined the effects of 2 multispecies direct-fed microbial (DFM) supplements on ruminal and plasma metabolome of early-lactation dairy cows using a high-coverage untargeted metabolomics approach. A total of 45 multiparous Holstein cows (41 ± 7 DIM) were enrolled for the 14-d pre-experimental and 91-d experimental period and were a subset from a lactation performance study, which used 114 cows. Cows were blocked using pre-experimental energy-corrected milk yield and randomly assigned within each block to 1 of 3 treatments: (1) corn silage–based diet with no DFM supplement (control; CON), (2) basal diet top-dressed with a mixture of Lactobacillus animalis and Propionibacterium freudenreichii at 3 × 109 cfu/d (PRO-A), or (3) basal diet top-dressed with a mixture of L. animalis , P. freudenreichii , Bacillus subtilis , and Bacillus licheniformis at 11.8 × 109 cfu/d (PRO-B). The basal diet was fed ad libitum daily as a TMR at 0600 and 1200 h for a duration of 91 d. Rumen fluid and blood samples were taken on d −3, 28, 49, 70, and 91 and immediately stored at −80°C. Before analysis, ruminal and plasma samples from d 28, 49, 70, and 91 were composited. An in-depth, untargeted metabolome profile of the composite rumen and plasma samples and the d −3 samples was developed by using a chemical isotope labeling/liquid chromatography-mass spectrometry (LC-MS)–based technique. Differentially abundant metabolites (taking into account fold change [FC] values and false discovery rates [FDR]) were identified with a volcano plot. In the rumen, compared with the CON diet, supplemental PRO-A increased (FC ≥1.2; FDR ≤0.05) the relative concentrations of 9 metabolites, including 2-hydroxy-2,4-pentadienoic acid, glutaric acid, quinolinic acid, and shikimic acid, and PRO-B increased relative concentrations of 16 metabolites, including 2-hydroxy-2,4-pentadienoic acid, glutaric acid, 16-hydroxypalmitic acid, and 2 propionate precursors (succinic and methylsuccinic acids). Relative to PRO-A, supplemental PRO-B increased (FC ≥1.2; FDR ≤0.05) relative rumen concentrations of 3 metabolites, 16-hydroxypalmitic acid, indole-3-carboxylic acid, and 5-aminopentanoic acid, but reduced relative rumen concentrations of 13 metabolites, including carnitine, threonic acid, and shikimic acid. Compared with the CON diet, relative concentrations of 13 plasma metabolites, including myxochelin A and glyceraldehyde, were increased (FC ≥1.2; FDR ≤0.05) by PRO-A supplementation, whereas those of 9 plasma metabolites, including 4-(2-aminophenyl)-2,4-dioxobutanoic acid, N-acetylornithine, and S-norlaudanosolin, were reduced (FC ≤0.83; FDR ≤0.05). Supplemental PRO-B increased (FC ≥1.2; FDR ≤0.05) relative concentrations of 9 plasma metabolites, including trans -o-hydroxybenzylidenepyruvic acid and 3-methylsalicylaldehyde, and reduced relative concentrations of 4 plasma metabolites, including β-ethynylserine and kynurenine. Pathway analysis of the differentially abundant metabolites in both rumen and plasma revealed that these metabolites are involved in AA and fatty acid metabolism and have antimicrobial and immune-stimulating properties. The results of this study demonstrated that dietary supplementation with either PRO-A or PRO-B altered the plasma and ruminal metabolome. Notably, ruminal and plasma metabolites involved in the metabolism of AA and fatty acids and those with immunomodulatory properties were altered by either or both of the 2 microbial additives. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) possess several desirable properties, including a homogeneous crystal structure, variable porosity, high surface area, and a notable adsorption affinity, making them highly promising contenders for deployment as electrode materials in supercapacitors (SCs) and water electrolyzers, which are acknowledged for the ever‐increasing demand for instantaneous energy. Herein, we report the rationally assembled Ni‐Co‐based bimetallic MOF compounds using a glutaric acid as an organic ligand and low‐temperature hydrothermal treatment that surmounts the electrocatalytic and electrochemical charge storage activity in an alkaline medium. The NiCo‐MOF surpassed the hydrogen evolution reaction (HER) among other as‐synthesized materials, exhibiting the least overpotential of 182 mV at 10 mA/cm2 of current density, showed splendid kinetics with a turnover frequency of 2.86 s−1, and higher stability after 1000 HER cycles in 1 M KOH. Furthermore, NiCo‐MOF impetuses were employed for SC application and displayed the highest specific capacitance of 978 F/g than Ni‐MOF (706 F/g) and Co‐MOF (91 F/g) at 1 A/g of current density. Theoretical studies exhibited that the optimal electronic coupling and synergistic effect due to Ni‐Co sites enhances the overall electronic properties of NiCo‐MOF. Therefore, enhancing its electrochemical performance concerning water‐splitting and charge storage. This study showcases a novel approach for producing ultrathin and flexible bimetallic MOF‐based electrode material to enrich the performance in electrocatalytic HER and SCs. [ABSTRACT FROM AUTHOR]

A process for synthesizing UV-curable ester/acrylate precursors from dicarboxylic acid mixtures, oxidized chemical recycling products of HDPE milk bottles, has been developed. The behavior and properties of the non-purified oxidized products were compared to its commercial diacid single components in producing the precursors. Two as-received oxidized products obtained at different conditions, i.e., Oxi-1 and Oxi-2, containing molar compositions of succinic acid (C4): glutaric acid (C5): adipic and longer dicarboxylic acids (C6+) of 55: 23: 22 and 67: 9: 24, were employed. The precursors were produced at high yields by end-capping the carboxylic groups with hydroxyethyl acrylate, utilizing p-TSA catalyst and MEHQ radical scavenger. With 5 mol% p-TSA and 3 wt% MEHQ, a reaction at 120 °C for 2 h was effective for synthesizing the precursors from Oxi-1, Oxi-2, and succinic acid. However, the optimal condition for adipic acid was at 140 °C for 4 h, implying lower esterification reactivity due to its longer methylene sequence. All ester/acrylate precursors were fully cured under UV lights within 10 min. DMA results of cured films from neat precursors (100CL-series) indicate that those derived from longer diacids yielded crosslinked networks with relatively lower Tg and rubbery plateau. However, when only 10% of the precursors were used as crosslinkers for acrylic acid/ethyl-hexyl acrylate (10CL-series), the influence of the starting material's diacid composition on the film's properties was lowered. The oxidized products from the nitric oxidation of HDPE have a high potential as value-added starting materials for UV-crosslinkers comparable to those from pure commercial diacids. [ABSTRACT FROM AUTHOR]

The crystal structures and the supramolecular architectures of a series of novel salts originating from 2,4-diaminopyrimidine and four different chain dicarboxylic acids are reported. For this purpose, 2,4-diaminopyrimidin-1-ium 2,2′-thio(acetic)acetate (1), 2,4-diaminopyrimidin-1-ium monoglutarate (2), 2,4-diaminopyrimidin-1-ium 3,3′-dithio(propionic)propionate (3) and 2,4-diaminopyrimidin-1-ium suberate (4) were synthesized in good to high yields from 2,4-diaminopyrimidine and appropriate dicarboxylic acids (2,2′-thiodiacetic acid, glutaric acid, 3,3′-dithiodipropionic acid and suberic acid, respectively). Each of the compounds were formed as a monohydrate and compound 4 additionally co-crystallized with the suberic acid molecule. Despite the similar structures of compounds 1 and 2 as well as 3 and 4, subtle but important differences are observed in their crystal packing and H-bonding patterns, especially between 3 and 4. Supramolecular self-assemblies can be distinguished through different interactions considering anions, leading to diverse H-bonding motifs, which also include sulphur atoms in 1 and 3, at the upper level of supramolecular architecture. Notably, the basic motif is always the same—2,4-diaminopyrimidine-based homosynthon R22(8) via N-H∙∙∙N interactions. The impact of diverse types of intermolecular interactions was evaluated by Hirshfeld analysis, while the propensity of atom pairs of elements to build interactions was calculated using enrichment ratios. Although compounds 1 and 3 contain S-atoms, the percentage of S-derived interactions is rather low. In 1, the contribution of S∙∙∙H/H∙∙∙S, S∙∙∙C/C∙∙∙S, S∙∙∙N/N∙∙∙S intermolecular contacts is 5.7%. In 2, the contribution of S∙∙∙H/H∙∙∙S accounts for only 0.6%. [ABSTRACT FROM AUTHOR]

A series of cocrystals featuring an isoniazid derivative was synthesized and characterized. Isoniazid was derivatised using acetone to make N′-(propan-2-ylidene)pyridine-4-carbohydrazide (izact). An attempt to form seven new cocrystals was made, which involved cocrystalizing izact an aliphatic dicarboxylic acid of varying chain lengths ranging from malonic acid (C3) to sebacic acid (C10), excluding succinic acid (C4) since this cocrystal was reported before. Out of these, only five cocrystals were successfully synthesized; since an attempt to form a cocrystal with malonic acid (C3) and glutaric acid (C5) failed, leaving the successful cocrystals to contain dicarboxylic acids ranging from adipic acid (C6) to sebacic acid (C10). These izact–dicarboxylic acid cocrystals were then compared to their isoniazid counterparts, as well as that with the previously reported izact–C4 cocrystal. This comparison showed that the cocrystals of izact with C4, C6, C8 were isostructural, while the other cocrystals reported here showed unique aspects that differentiated them from their counterparts. Single-crystal X-ray diffraction (SC-XRD) was used to determine the crystal structures, while powder X-ray diffraction (PXRD) was used to determine the bulk phase purity. Differential scanning calorimetry was used to determine any additional phases but only melting was observed. [ABSTRACT FROM AUTHOR]

Changes in pharmacokinetics and endogenous metabolites may underlie additive biological effects of concomitant use of antipsychotics and opioids. In this study, we employed untargeted metabolomics analysis and targeted analysis to examine the changes in drug metabolites and endogenous metabolites in the prefrontal cortex (PFC), midbrain, and blood of rats following acute co-administration of quetiapine and methadone. Rats were divided into four groups and received cumulative increasing doses of quetiapine (QTP), methadone (MTD), quetiapine + methadone (QTP + MTD), or vehicle (control). All samples were analyzed using liquid chromatography-mass spectrometry (LC–MS). Our findings revealed increased levels of the quetiapine metabolites: Norquetiapine, O-dealkylquetiapine, 7-hydroxyquetiapine, and quetiapine sulfoxide, in the blood and brain when methadone was present. Our study also demonstrated a decrease in methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in the rat brain when quetiapine was present. Despite these findings, there were only small differences in the levels of 225–296 measured endogenous metabolites due to co-administration compared to single administrations. For example, N-methylglutamic acid, glutaric acid, p-hydroxyphenyllactic acid, and corticosterone levels were significantly decreased in the brain of rats treated with both compounds. Accumulation of serotonin in the midbrain was additionally observed in the MTD group, but not in the QTP + MTD group. In conclusion, this study in rats suggests a few but important additive metabolic effects when quetiapine and methadone are co-administered. [ABSTRACT FROM AUTHOR]

Three tetrazole-based carboxylic acids, 3,3-di(1H-tetrazol-5-yl)pentanedioic acid (H4L1), 2-(5-pyridin-4-yl-tetrazol-2-yl)propionic anion (HL2), and 5-(2-pyridyl)tetrazole-2-acetic acid (HL3), were selected as ligands to synthesize three new Pb(II)-coordination polymers, [Pb2(L1)] · H2O (1), [Pb(L2)(NO3−)] (2), and [Pb(L3)2(H2O)] · H2O (3). These metal-organic frameworks have been characterized by elemental analysis, FT-IR, and single crystal X-ray diffraction. The results demonstrated that 1 displayed a 3-D network, while 2 and 3 show 2-D framework and 1-D chain, respectively. The differential scanning calorimetry and thermogravimetric analyses gave thermodynamic parameters (ΔH, ΔS, and ΔG). The results showed that 1–3 may be promising high-energy materials. [ABSTRACT FROM AUTHOR]

This article addresses the soldering of larger components onto ceramic substrates with thick printed copper patterns with a reduced amount of flux or using glutaric acid as a flux substitute. The main goal of the research was to create high quality connections by soldering on ceramic substrates, together with elimination of conventional flux from the process, and also to study the reliability of soldered joints on ceramic substrates under thermal shock ageing. The mock-up chips were used in the test and for this reason the test was primarily focused on bottom joint in the structure or sandwich structures. In the experiment, vacuum soldering using formic acid vapors to reduce oxides was used. Then all samples were observed under X-RAY radiation and selected samples were submitted for thermal shock testing (-40°C / 125°C / 1000 cycles). After the shock testing, another X-RAY scan with void area measurement and shear strength testing were realized. The results showed that our contacting soldering processes on ceramic substrates (with diluted flux or glutaric acid) are applicable and the selected samples also endures the shock ageing, especially bottom joint between ceramic substrate with Cu layer and solder alloy. The results also showed that void area and mechanical shear strength of soldered ceramic samples created with diluted flux or glutaric acid are relatively comparable with standard samples (FR-4).

In pursuit of understanding structure–property relationships for the melting point depression of binary eutectic mixtures, the influence of the anion on the solid–liquid (S–L) phase behavior was explored for mixtures of glutaric acid + tetraethylammonium chloride, bromide, and iodide. A detailed experimental evaluation of the S–L phase behavior revealed that the eutectic point is shifted toward lower temperatures and higher salt contents upon decreasing the ionic radius. The salt fusion properties were experimentally inaccessible owing to thermal decomposition. The data were inter- and extrapolated using various models for the Gibbs energy of mixing fitted to the glutaric-acid rich side only, which allowed for the assessment of the eutectic point. Fitting the experimental data to a two-parameter Redlich–Kister expansion with Flory entropy, the eutectic depth could be related to the ionic radius of the anion. The anion type, and in particular its size, can therefore be viewed as an important design parameter for the liquid window of other acid and salt-based deep eutectic solvents/systems. [ABSTRACT FROM AUTHOR]

Herein, a novel composite of Corchorus olitorius-derived biochar and Bi12O17Cl2 was fabricated and utilized for the degradation of tetracycline (TC) in a solar photo-oxidation reactor. The morphology, chemical composition, and interaction between the composite components were studied using various analyses. The biochar showed a TC removal of 52.7% and COD mineralization of 59.6% using 150 mg/L of the biochar at a pH of 4.7 ± 0.5, initial TC concentration of 163 mg/L, and initial COD of 1244 mg/L. The degradation efficiency of TC increased to 63% and the mineralization ratio to 64.7% using 150 mg/L of bare Bi12O17Cl2 at a pH of 4.7 ± 0.5, initial TC concentration of 178 mg/L, and COD of 1034 mg/L. In the case of biochar/Bi12O17Cl2 composite, the degradation efficiency of TC and COD mineralization ratio improved to 85.8% and 77.7% due to the potential of biochar to accept electrons which retarded the recombination of electrons and holes. The synthesized composite exhibited high stability over four succeeding cycles. According to the generated intermediates, TC could be degraded to caprylic acid and pentanedioic acid via the frequent attack by the reactive species. The prepared composite is a promising photocatalyst and can be applied in large-scale systems due to its high degradation and mineralization performance in a short time besides its low cost and stability. [ABSTRACT FROM AUTHOR]

The mixed dibasic acids (DBA) is a by-product during adipic acid (ADA) production by oxidation of cyclohexanol or cyclohexanone, which contains large amount of glutaric acid (GA) with ADA and succinic acid (SA). In this work, we have explored the feasibility of the coupled solution crystallization and melt crystallization for the purification of GA. To obtain fundamental thermodynamic properties for the process design, the gravimetric method was used to measure the solubility of the three dibasic acids in water from 293.15 K to 345.15 K at atmospheric pressure. The results showed that GA was the most soluble component while all solubility increased with increasing temperature. Therefore, it is reasonable to concentrate GA in the liquid phase by cooling crystallization. Similarly, the ternary solid-liquid melt equilibrium phase diagram was constructed based on the experimental data of the three binary subsystems (GA-ADA, GA-SA, ADA-SA). It was found that the concentrated GA after solvent evaporation could be purified by melt crystallization efficiently. Thus a coupled solution crystallization and melt crystallization process was designed. With the operated operating parameters, the purity of GA could reach 99.06% by secondary melt crystallization. Overall, the coupled solution crystallization and melt crystallization method to separate DBA has proven to be effective. [Display omitted] • A novel coupled solution crystallization and melt crystallization method. • Determination of solubility data of three kinds of diacid in water from 293.15 K to 345.15 K. • The solid - liquid equilibrium phase diagrams of three dibasic acids were established by extrapolation. • A process for separating mixed diacid and preparing high purity glutaric acid. [ABSTRACT FROM AUTHOR]

A straightforward and practical method has been developed to access α-substituted glutaric diesters from acrylates and aldehydes using visible light, with Eosin Y facilitating hydrogen atom transfer (HAT) and subsequent Giese-type addition. Also, sunlight has been successfully used as an alternative sustainable light source. The method has also been explored to access substituted 4,5-dihydro-2H-pyridazinones, which have potential biological and industrial applications. Comprehensive mechanistic investigations have been carried out. [ABSTRACT FROM AUTHOR]

The uptake of 63Ni(II), 152Eu(III) and 242Pu(IV) by hardened cement paste (HCP, CEM I) in the degradation stage II (pH ≈ 12.5, [Ca] ≈ 0.02 M) was investigated in the presence of a degradation leachate of UP2W, a polyacrylonitrile-based (PAN) material used as a filter aid in nuclear power plants. The degradation leachate with a concentration of dissolved organic carbon of ∼40 ppm was obtained from the degradation of UP2W in portlandite-buffered solutions for ca. 1100 days. Redox conditions in the Pu systems were buffered with hydroquinone, which defines mildly reducing conditions (pe + pH ≈ 10) where Pu(IV) is the predominant oxidation state. The degradation leachate investigated in this work is moderately sorbed by cement, with distribution ratios (Rd) of (0.35 ± 0.15) m3 kg−1. These values are 30 to 100 times greater than distribution ratios previously reported for proxy ligands of PAN degradation products, i.e., glutaric acid, α-hydroxyisobutyric acid and 3-hydroxybutyric acid. The presence of the degradation leachate induces a moderate decrease in the uptake of 63Ni(II), 152Eu(III) and 242Pu(IV) by cement, as compared to the sorption in the presence of the proxy ligands. Nevertheless, retention in the presence of the degradation leachate remains high for all investigated radionuclides, with Rd(63Ni(II)) ≈ 2 m3 kg−1, Rd(152Eu(III)) ≈ 100 m3 kg−1 and Rd(242Pu(IV)) ≈ 30 m3 kg−1. These observations possibly reflect that the multiple functionalities (–COOH, –OH, amide groups) expected in the macromolecules (10–15 kDa) present in the degradation leachate, can offer further binding/chelating capabilities compared to the small organic proxy ligands with at most bidentate binding. [ABSTRACT FROM AUTHOR]

To improve the solubility and dissolution rate of the BCS class II drug ketoconazole, five novel solid forms in 1:1 stoichiometry were obtained upon liquid-assisted grinding, slurry, and slow evaporation methods in the presence of coformers, namely, glutaric, vanillic, 2,6-dihydroxybenzoic, protocatechuic, and 3,5-dinitrobenzoic acids. Single-crystal X-ray diffraction analysis revealed that the hydroxyl/carboxylic acid...N-imidazole motif acts as the dominant supramolecular interaction in the obtained solid forms. The solubility of ketoconazole in distilled water significantly increased from 1.2 to 2165.6, 321.6, 139.1, 386.3, and 191.7 μg mL−1 in the synthesized multi-component forms with glutaric, vanillic, 2,6-dihydroxybenzoic, protocatechuic, and 3,5-dinitrobenzoic acid, respectively. In particular, the cocrystal form with glutaric acid showed an 1800-fold solubility increase in water concerning ketoconazole. Our study provides an alternative approach to improve the solubility and modify the release profile of poorly water-soluble drugs such as ketoconazole. [ABSTRACT FROM AUTHOR]

Chemical composition of sub-10 nm particles is crucial for understanding the atmospheric new particle formation (NPF) and subsequent particle growth. However, very limited chemical information is available in this diameter range due to the high technical requirements. In this work, we proposed a new operation mode of water-based condensation particle counter, which was termed as Scanning Flow Condensation Particle Counter (SFCPC). By altering the aerosol flow rate (Qa), this method could change supersaturation (S) rapidly. The inner S of SFCPC was evaluated by ammonium sulfate (AS) and tungsten oxide particles. It decreased more and more sharp when Qa varied from 400 to 80 cm3 min−1, corresponding to the S in the range of 14.02%–26.39%, which could activate AS in 3.6–5.4 nm. Hygroscopicity parameter κ was obtained directly from the selected particle diameter and measured counting efficiency. For AS-levoglucosan/sucrose mixtures, linear relationship between κ and organic mass fraction forg was successfully established down to 3.5 nm. We also measured κ of several NPF relevant organics in 5–8 nm (0.121 ± 0.055, 0.123 ± 0.035, 0.132 ± 0.032, 0.129 ± 0.023 and 0.142 ± 0.023 for cis-pinonic acid, benzoic acid, malonic acid, succinic acid, and glutaric acid, respectively). This new method has been evaluated in lab for the capability of measuring κ. The size-resolved linear relationship indicated that SFCPC could be used to infer forg. The rapid S change and activated diameter range make this method suitable for field measurements. The provided κ and forg of sub-10 nm particles is an important complement for the understanding of new particle formation. Copyright © 2023 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

Nitroglycerin (NG) is a high explosive that is difficult to handle in its liquid form, where the entrapment of gaseous NG bubbles results in its high sensitivity to impact (<0.25 J). NG‐based materials are traditionally prepared by complex mixing processes where desensitisation is of major concern. Instead of using a mixing procedure here we demonstrate the successful synthesis of dynamite‐like materials by using a single step bottom‐up approach to form a polymeric host matrix (PM) for NG from a solution which contains the explosive and the matrix precursors. For this purpose, an epoxidized vegetable oil mixed with nitroglycerin (oil to NG mass ratio of 60/40) is polymerized at 100 °C for 30 h by using glutaric acid as crosslinking agent. No degradation of NG under these conditions is observed. The activation energy of NG desorption from the PM (51.9 kJ/mol) is of the same order of magnitude as the one reported in literature for a double‐base powder (81.9 kJ/mol). An accelerated NG desorption is observed as temperature increases. This can be attributed to a slow diffusion mechanism of the explosive from the volume to the surface of the material, where it evaporates. The ignition of NG/PM in air by an open flame leads to a self‐sustained combustion, in which a part of nitroglycerin decomposes in the polymer matrix. Conversely, NG/PM monolithic and granular loads are not ignited by the explosion of the primer in a 9 mm calibre casing. The shockwave released by a detonator on a small NG/PM cylindrical charge (≈1.5 g) does not detonate it, but only makes it deflagrate. Our results show that this novel single‐step synthesis of NG trapped in a polymeric matrix is a very effective approach for desensitizing it to any form of stress. [ABSTRACT FROM AUTHOR]

Impregnating fabrics with shear thickening fluid (STF) improves impact resistance. In this study modification of polyethylene glycol (PEG 200) was carried out to enhance the thickening behavior of STF. The rheological analysis shows tunned STFs by PEG modification with glutaric acid and oxalic acid increase the maximum viscosity by about 10.33 and 3.28 folds with respect to unmodified STF. Additionally, the alternations of a liquid dispersion medium (PEG) led to higher chain length in STFs, representing superior interaction between media and particles by profuse H-bonding. The results confirmed that increasing the molecular length of PEG-based on STF caused a significant improvement in the knife and spike stabbing impact resistance, quasi-static, and yarn pull-out performance of the neat fabric. In addition, it was realized, by increasing impact velocity the energy absorption ability of STF-treated fabric composite increases. Additionally, a regression analysis using artificial intelligence was applied to study the effect of the pull-out rate on the mechanical response of different materials. Using a third-order polynomial for AI regression model, it turned out that while the pull-out rate has the least influence on untreated E-glass fabrics (UEG) response, for other materials, the behavior changes significantly by increasing the rate from 100 to 400 mm/min. [ABSTRACT FROM AUTHOR]

The aim of this work is to compare the effects of chemical and photochemical functionalization on the mechanical properties of PET fabric and its adhesion to nitrile rubber (NBR). The photochemical functionalization was performed by UV irradiation of PET fabric in the presence of glutaric acid peroxide at a temperature of 60 °C for different exposure times (i.e. 60, 90 and 120 min). The chemical functionalization (i.e. hydrolysis) of PET fabrics was performed by NaOH solution at a temperature of 60 °C for different times (i.e. 60, 120, 240 and 360 min). The tensile properties of the functionalized fibers were also evaluated. The functionalized PETs were evaluated for H-pull and T-peel adhesion to NBR. It was found that both treatment methods created functional groups on the PET surface. However, carboxylation of PET under GAP/UV irradiation generated much more OH groups on the PET surface (i.e. 4.5 times). The hydrolysis of PET in NaOH solution for more than 60 min caused a significant decrement in the tensile strength contrary to carboxylation under GAP/UV irradiation. It was also found that pullout and T-peel adhesions to NBR decreased in the case of hydrolysis of PET while they increased about 33 and 12% for GAP/UV irradiated PET, respectively. [ABSTRACT FROM AUTHOR]

Mole fraction solubilities are reported for acenaphthene, o-acetoacetanisidide, anthracene, benzil, benzoic acid, benzoin, 4-tert-butylbenzoic acid, 1-chloroanthraquinone, 4-chlorobenzoic acid, 2-chloro-5-nitrobenzoic acid, 4-chloro-3-nitrobenzoic acid, 3,4-dichlorobenzoic acid, 3,4-dimethoxybenzoic acid, 3,5-dinitrobenzoic acid, diphenyl sulphone, 2-ethylanthraquinone, 2-naphthoxyacetic acid, 2-hydroxybenzoic acid, N-hydroxyphthalimide, 2-methoxybenzoic acid, 4-methoxybenzoic acid, 3-methylbenzoic acid, 2-methyl-3-nitrobenzoic acid, 3-methyl-4-nitrobenzoic acid, 4-methyl-3-nitrobenzoic acid, 3-nitrobenzoic acid, 4-nitrobenzoic acid, salicylamide, 3,4,5-trimethoxybenzoic acid, trans-stilbene, thioxanthen-9-one and xanthene dissolved in dimethyl adipate at 298.15 K. Results of these measurements, combined with published literature data for adipic acid, glutaric acid and succinic acid, are used to derive predictive Abraham model correlations. The derived correlations back-calculate the observed solubility data to within ±0.12 log units. [ABSTRACT FROM AUTHOR]

The present study deals with the chemical modification of polyethylene glycol (PEG) based on shear thickening fluids (STFs) and their application to improve the ballistic impact and quasi-static resistance performance of 3D E-glass fabrics. The carrier fluid (PEG 200) was modified with two different agents, oxalic acid and glutaric acid. The modified PEGs were then characterized by FTIR analysis. The rheological analysis of modified STF using glutaric (G/STF) and oxalic acid (O/STF) showed an improvement in peak viscosity by 10.33 and 3.28 times compared to pure STF (P/STF), respectively. Moreover, PEG modification resulted in higher chain length and a higher number of hydrophilic functional groups, representing superior media-particle interaction through abundant H-bonding. As a result of improved viscosity, the ballistic resistance and quasi-static performance of modified STF-treated fabrics were enhanced compared to that of P/STF-treated fabrics. A two-step artificial intelligence regression analysis was performed to predict quasi-static puncture resistance at different puncture speeds. The results showed a strong correlation between the load-deformation behavior and the loading speed. [ABSTRACT FROM AUTHOR]

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The pharmacopoeial test method "Intrinsic Dissolution" (Ph.Eur. 2.9.29) is used to study the rate of dissolution for powders of active pharmaceutical ingredients normalized by the surface area. Therefore, powders are compacted into a special metal die holder, which is immersed into a dissolution vessel of the dissolution test apparatus (described in Ph.Eur. 2.9.3). However, in some cases, the test cannot be performed because the compacted powder would not stay in the die holder when in contact with the dissolution medium. In this study, we investigated the removable adhesive gum (RAG) as an alternative to the official die holder. Intrinsic dissolution tests were carried out to exemplify the use of the RAG for this purpose. As model substances, acyclovir and its co-crystal with glutaric acid were used. The RAG was validated for compatibility, release of extractables, unspecific adsorption and the ability to block drug release through the covered surfaces. The results showed that the RAG leaked no unwanted substances, showed no adsorption of acyclovir and blocked its release from covered surfaces. The intrinsic dissolution tests revealed, as expected, a constant release of drug with a small standard deviation between replicates. It was possible to distinguish the acyclovir release from the co-crystal and from the pure drug compound. In conclusion, the findings of this study suggest to consider removable adhesive gum as an easy-to-use and inexpensive alternative to the compendial die holder in intrinsic dissolution tests. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: Glutaric acidemia type 1 (GA1) is a rare autosomal recessive inherited metabolic disorder caused by variants in the gene encoding the enzyme glutaryl-CoA dehydrogenase (GCDH). The estimated prevalence of GA1 and the mutational spectrum of the GCDH gene vary widely according to race and region. The aim of this study was to assess the acylcarnitine profiles and genetic characteristics of patients with GA1 in Fujian Province, southeastern China. Results: From January 2014 to December 2022, a total of 1,151,069 newborns (631,016 males and 520,053 females) were screened using MS/MS in six newborn screening (NBS) centers in Fujian Province and recruited for this study. Through NBS, 18 newborns (13 females and 5 males) were diagnosed with GA1. Thus, the estimated incidence of GA1 was 1 in 63,948 newborns in Fujian province. In addition, 17 patients with GA1 were recruited after clinical diagnosis. All but one patient with GA1 had a remarkable increase in glutarylcarnitine (C5DC) concentrations. The results of urinary organic acid analyses in 33 patients showed that the concentration of glutaric acid (GA) increased in all patients. The levels of C5DC and GA in patients identified via NBS were higher than those in patients identified via clinical diagnosis (P < 0.05). A total of 71 variants of 70 alleles were detected in patients with GA1, with 19 different pathogenic variants identified. The three most prevalent variants represented 73.23% of the total and were c.1244-2 A > C, p.(?) (63.38%), c.1261G > A, p.Ala421Thr (5.63%), and c.406G > T, p.Gly136Cys (4.22%). The most abundant genotype observed was c.[1244-2 A > C]; [1244-2 A > C] (18/35, 52.43%) and its phenotype corresponded to high excretors (HE, GA > 100 mmol/mol Cr). Conclusions: In conclusion, we investigated the biochemical and molecular features of 35 unrelated patients with GA1. C5DC concentrations in dried blood spots and urinary GA are effective indicators for a GA1 diagnosis. Our study also identified a GCDH variant spectrum in patients with GA1 from Fujian Province, southeastern China. Correlation analysis between genotypes and phenotypes provides preliminary and valuable information for genetic counseling and management. [ABSTRACT FROM AUTHOR]

Charge transfer complexes (CTCs) formed between TiO 2 and chelating ligands have attracted extensive attention for photocatalytic applications under visible radiation due to their increased visible light absorption. Different TiO 2 -based CTCs have been widely studied. However, the sensitization of TiO 2 to visible light by functionalization with glutaric acid (TiO 2 -GA) and its photocatalytic performance under visible light radiation have not yet been investigated, as far as the authors know. In this study, visible-light-sensitive TiO 2 -GA nanomaterials were synthesized via sol-gel and calcined under static air at 270 °C. The as-prepared TiO 2 -GA CTCs were characterized by XRPD, FTIR, TGA, DRS, PL, EPR and XPS techniques. FTIR data supported the formation of the CTC through bidentate chelating interaction between TiO 2 and GA. TiO 2 -GA CTCs calcined at 270 °C under static air exhibited a long absorption tail in the visible light spectrum mainly due to the formation of F + centers. The high content of GA molecules bounded to the TiO 2 surface was not beneficial for photocatalytic performance of the TiO 2 -GA CTCs, since these molecules reduced the active sites on the nanostructure surface, resulting in a lower production of superoxide radicals by the TiO 2 -GA CTCs. Our findings indicated that: a) TiO 2 -GA CTCs are capable to degrade antibiotic liquid pollutants via interactions with superoxide radicals and also, b) provided fundamental insights into the influence of bulk Ti 3 + defects and bulk oxygen vacancies on photocatalytic performance and photochemical properties of TiO 2 -based CTCs. [Display omitted] • Visible-light-sensitive charge transfer complexes (CTCs) formed between TiO 2 and glutaric acid (GA) were obtained via sol-gel route, using two different approaches and calcined under static air at 270 °C (TiO 2 -GA1 270 and TiO2-GA2 270). • The functionalization of anatase nanoparticles with glutaric acid and the influence of extrinsic point defects on lattice parameters, optical, photochemical and photocatalytic properties of the TiO 2 -GA CTCs were investigated in detail. • The tetracycline photodegradation results using benzoquinone (BQ) and isopropanol (IPA), as scavengers, highlighted the key role of the superoxide radical in the TC degradation by the TiO 2 -GA CTCs under low-power visible light radiation. • TiO 2 -GA1 270 CTC exhibited the highest photocatalytic performance for TC degradation. [ABSTRACT FROM AUTHOR]

Glutamate carboxypeptidase II (GCPII), localized on the surface of astrocytes and activated microglia, regulates extracellular glutamate concentration in the central nervous system (CNS). We have previously shown that GCPII is upregulated in activated microglia in the presence of inflammation. Inhibition of GCPII activity could reduce glutamate excitotoxicity, which may decrease inflammation and promote a 'normal' microglial phenotype. 2-(3-Mercaptopropyl) pentanedioic acid (2-MPPA) is the first GCPII inhibitor that underwent clinical trials. Unfortunately, immunological toxicities have hindered 2-MPPA clinical translation. Targeted delivery of 2-MPPA specifically to activated microglia and astrocytes that over-express GCPII has the potential to mitigate glutamate excitotoxicity and attenuate neuroinflammation. In this study, we demonstrate that 2-MPPA when conjugated to generation-4, hydroxyl-terminated polyamidoamine (PAMAM) dendrimers (D-2MPPA) localize specifically in activated microglia and astrocytes only in newborn rabbits with cerebral palsy (CP), not in controls. D-2MPPA treatment led to higher 2-MPPA levels in the injured brain regions compared to 2-MPPA treatment, and the extent of D-2MPPA uptake correlated with the injury severity. D-2MPPA was more efficacious than 2-MPPA in decreasing extracellular glutamate level in ex vivo brain slices of CP kits, and in increasing transforming growth factor beta 1 (TGF-β1) level in primary mixed glial cell cultures. A single systemic intravenous dose of D-2MPPA on postnatal day 1 (PND1) decreased microglial activation and resulted in a change in microglial morphology to a more ramified form along with amelioration of motor deficits by PND5. These results indicate that targeted dendrimer-based delivery specifically to activated microglia and astrocytes can improve the efficacy of 2-MPPA by attenuating glutamate excitotoxicity and microglial activation. [Display omitted] [ABSTRACT FROM AUTHOR]

Conjugation via disuccinimidyl homobifunctional linkers is reported in the literature as a convenient approach for the synthesis of glycoconjugate vaccines. However, the high tendency for hydrolysis of disuccinimidyl linkers hampers their extensive purification, which unavoidably results in side-reactions and non-pure glycoconjugates. In this paper, conjugation of 3-aminopropyl saccharides via disuccinimidyl glutarate (DSG) was exploited for the synthesis of glycoconjugates. A model protein, ribonuclease A (RNase A), was first considered to set up the conjugation strategy with mono- to tri- mannose saccharides. Through a detailed characterization of synthetized glycoconjugates, purification protocols and conjugation conditions have been revised and optimized with a dual aim: ensure high sugar-loading and avoid the presence of side reaction products. An alternative purification approach based on hydrophilic interaction liquid chromatography (HILIC) allowed the formation of glutaric acid conjugates to be avoided, and a design of experiment (DoE) approach led to optimal glycan loading. Once its suitability was proven, the developed conjugation strategy was applied to the chemical glycosylation of two recombinant antigens, native Ag85B and its variant Ag85B-dm, that are candidate carriers for the development of a novel antitubercular vaccine. Pure glycoconjugates (≥99.5%) were obtained. Altogether, the results suggest that, with an adequate protocol, conjugation via disuccinimidyl linkers can be a valuable approach to produce high sugar-loaded and well-defined glycovaccines. [ABSTRACT FROM AUTHOR]

Ultrastructural features of striatal white matter and cells in an in vivo model of glutaric acidemia type I created by intracerebral injection of glutaric acid (GA) were analyzed by transmission electron microscopy and immunohistochemistry. To test if the white matter damage observed in this model could be prevented, we administered the synthetic chemopreventive molecule CH38 ((E)‐3‐(4‐methylthiophenyl)‐1‐phenyl‐2‐propen‐1‐one) to newborn rats, previous to an intracerebroventricular injection of GA. The study was done when striatal myelination was incipient and when it was already established (at 12 and 45 days post‐injection [DPI], respectively). Results obtained indicate that that the ultrastructure of astrocytes and neurons did not appear significantly affected by the GA bolus. Instead, in oligodendrocytes, the most prominent GA‐dependent injury defects included endoplasmic reticulum (ER) stress and nuclear envelope swelling at 12 DPI. Altered and reduced immunoreactivities against heavy neurofilament (NF), proteolipid protein (PLP), and myelin‐associated glycoprotein (MAG) together with axonal bundle fragmentation and decreased myelin were also found at both ages analyzed. CH38 by itself did not affect striatal cells or axonal packages. However, the group of rats that received CH38 before GA did not show evidence neither of ER stress nor nuclear envelope dilation in oligodendrocytes, and axonal bundles appeared less fragmented. In this group, labeling of NF and PLP was similar to the controls. These results suggest that the CH38 molecule is a candidate drug to prevent or decrease the neural damage elicited by a pathological increase of GA in the brain. Optimization of the treatments and identification of the mechanisms underlying CH38 protective effects will open new therapeutic windows to protect myelin, which is a vulnerable target of numerous nervous system diseases. [ABSTRACT FROM AUTHOR]

As an important five-carbon platform chemical to synthesize polyesters and polyamides, glutaric acid is widely used in numerous biochemical fields such as consumer goods, textile, and footwear industries. However, the application of glutaric acid is limited by the low yield of its bio-production. In this study, a metabolically engineered Escherichia coli LQ-1 based on 5-aminovalerate (AMV) pathway was used for glutaric acid fed-batch fermentation. Given the significance of nitrogen source in the bio-production of glutaric acid by AMV pathway, a novel nitrogen source feeding strategy feedbacked by real-time physiological parameters was proposed after evaluating the effects of nitrogen source feeding (such as ammonia and ammonium sulfate) on glutaric acid bio-production. Under the proposed nitrogen source feeding strategy, a significantly improved glutaric acid production of 53.7 g L–1 was achieved in a 30 L fed-batch fermentation by the metabolically engineered E. coli LQ-1, which was an improvement of 52.1% over pre-optimization. Additionally, a higher conversion rate of 0.64 mol mol–1 (glutaric acid/glucose) was obtained compared with the previously reported bio-production of glutaric acid with E. coli. These results indicated that the nitrogen source feeding strategy proposed in this study will be useful for achieving the efficient and sustainable bio-based production of glutaric acid. [ABSTRACT FROM AUTHOR]

Optically-active luminescent materials based on lanthanoid ions attract significant attention due to their unique spectroscopic properties and the possibility of application as chemical sensors. Five isostructural lanthanoid metal organic frameworks, namely {[Pr(3,4-PDA)(Glu)0.5(H2O)2]CH3CN}(1) and [Ln(3,4-PDA)(Glu)0.5(H2O)2]: Ln = Nd (2), Sm (3), Eu (4), and Tb (5) (where 3,4-PDA = pyridine-3,4-dicarboxylic acid, Glu = glutaric acid), synthesized via the solvothermal method are reported. These lanthanoid metal–organic frameworks were characterized by FTIR, single-crystal X-ray diffraction, powder X-ray diffraction, BET, Hirshfeld surface analysis, DFT calculations, electronic spectroscopy, and photoluminescence techniques. MOFs 1–5 show porous two-dimensional (2D) structures. The luminescence properties of MOFs 4 and 5 demonstrated the range of sensing capabilities for some toxic heavy metals. However, MOFs 4 and 5 are highly sensitive for the detection of Pb2+, exhibiting the most effective luminescence quenching with the lowest detectable change in the signal occurring at ∼0.014 and ∼0.013 ppm of Pb2+ with MOFs 4 and 5, respectively, at room temperature in minutes. The MOF-based luminescence sensors designed in this paper demonstrate a successful and feasible strategy to use pyridine-3,4-dicarboxylic acid-based ligand as an antenna, which can efficiently sensitize Eu3+ and Tb3+ emission. MOFs 4 and 5 show great potential in the application of environmental detection of Pb2+ in water. [ABSTRACT FROM AUTHOR]

Short peptides containing the Arg-Gly-Asp (RGD) fragment can selectively bind to integrins on the surface of tumor cells and are attractive transport molecules for the targeted delivery of therapeutic and diagnostic agents to tumors (for example, glioblastoma). We have demonstrated the possibility of obtaining the N- and C-protected RGD peptide containing 3-amino-closo-carborane and a glutaric acid residue as a linker fragment. The resulting carboranyl derivatives of the protected RGD peptide are of interest as starting compounds in the synthesis of unprotected or selectively protected peptides, as well as building blocks for preparation of boron-containing derivatives of the RGD peptide of a more complex structure. [ABSTRACT FROM AUTHOR]

The applicability of different solvent-free approaches leading to the amorphization of active pharmaceutical ingredients (APIs) was tested. Ethenzamide (ET), an analgesic and anti-inflammatory drug, and two ethenzamide cocrystals with glutaric acid (GLU) and ethyl malonic acid (EMA) as coformers were used as pharmaceutical models. Calcinated and thermally untreated silica gel was applied as an amorphous reagent. Three methods were used to prepare the samples: manual physical mixing, melting, and grinding in a ball mill. The ET:GLU and ET:EMA cocrystals forming low-melting eutectic phases were selected as the best candidates for testing amorphization by thermal treatment. The progress and degree of amorphousness were determined using instrumental techniques: solid-state NMR spectroscopy, powder X-ray diffraction, and differential scanning calorimetry. In each case, the API amorphization was complete and the process was irreversible. A comparative analysis of the dissolution profiles showed that the dissolution kinetics for each sample are significantly different. The nature and mechanism of this distinction are discussed. [ABSTRACT FROM AUTHOR]

The high potency of the tetrahydrofuran-containing acetogenins (THF-ACGs) against a broad range of human cancer cell lines has stimulated interest in structurally simpler mimetics. In this context, we have previously reported THF-ACG mimetics in which the THF and butenolide moieties of a mono-THF-ACG were replaced with carbohydrate and thiophene residues, respectively. In the present study, towards the targeting of these carbohydrate analogues to prostate cancer (PCa), we synthesized prodrugs in which a parent thiophene or butenolide congener was conjugated through a self-immolative linker to 2-[3-(1,3-dicarboxypropyl)ureido] pentanedioic acid (DUPA), a highly specific ligand for prostate-specific membrane antigen (PSMA), which is overexpressed on prostate tumors. Both prodrugs were found to be more active against receptor positive LNCaP than receptor-negative PC-3 cells, with 2.5 and 12 times greater selectivity for the more potent thiophene analog and the less active butenolide congener, respectively. This selectivity for LNCaP over PC-3 contrasted with the behavior of the parent drugs, which showed similar or significantly higher activity for PC-3 compared to LNCaP. These data support the notion that higher activity of these DUPA-derived prodrugs against LNCaP cells is connected to their binding to PSMA and suggest that the conjugation of PSMA ligands to this family of cytotoxic agents may be effective for targeting them to PCa. [ABSTRACT FROM AUTHOR]

The evolution of highly efficient adsorbents has received attention around the world due to the importance of removing pollution from water. In the current work, a new and stable silica/coordination polymer nanoporous composite was prepared via the layer-by-layer method and characterized with various physicochemical methods. Aminopropyl-functionalized SiO2 was consecutively coated with Ni2+ and glutaric acid (GA) in 10 steps to prepare SiO2/Ni-GA. The removal efficiency of SiO2-based nanoporous composite towards cationic and anionic dyes was considered at room temperature. The results showed that SiO2/Ni-GA is a good adsorbent for all selected dyes (Congo red, CR; methyl orange, MO; and malachite green, MG). However, CR with higher removal efficiency (94%) was selected for further investigations. The high removal efficiency of SiO2/Ni-GA towards CR is related to hydrogen bonding and relatively good surface area. The adsorption process was well fitted with the second-order kinetic model and the recovered adsorbent was shown to be reusable for three consecutive cycles. [ABSTRACT FROM AUTHOR]

Harvested avocado fruits can be potentially exposed both to pre- and post-harvest factors that may influence the susceptibility of fruit to quality loss. Regular air (RA) storage consists of approximately 78% nitrogen, 21% oxygen, 0.3% carbon dioxide, and smaller amounts of some other gasses. A controlled atmosphere (CA) is a changed atmosphere that is used to delay respiration and reduce fungal and physiological deterioration, and it is an appropriate and practical technology for prolonging the shelf life and maintaining the quality of fruits on a large scale. An experiment was conducted by collecting fruits from two different avocado orchards (Bartolillo and Quilhuica) during two harvest seasons based on dry matter content and two subsequent years. The current study was designed to investigate the changes in polar metabolites, phenolic compounds, and fatty acids in the skin of Hass avocados stored under two distinct conditions. Bartolillo orchard fruits were mostly correlated to linoleic and oleic acid as important variables. For Quilhuica, fruits were mostly correlated with palmitoleic, palmitic, and oleic acids. Phenolic content increased at the beginning of storage and decreased at the end of storage for one orchard and contrarily for others, indicating that the result was dependent on the orchard and storage condition. Serine, glutaric acid, xylitol and D-mannitol were the polar metabolites that most correlated with fruits of the Quilhuica orchard while ß-sitosterol and gluconic were related to fruits of the Bartolillo orchard. The differences in fatty acids, polar metabolites and phenolics were dependent on orchard and storage conditions. [ABSTRACT FROM AUTHOR]

Two new Zn(ii) coordination complexes [Zn(L)(dna)(H2O)] (1) and [Zn(L)(glu)]2·H2O (2) (L = 2-(4-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, H2dna = 3,5-dinitrosalicylic acid, H2glu = glutaric acid) have been hydrothermally synthesized and characterized by single crystal X-ray diffraction, elemental analysis, fluorescence spectrum, and infrared spectroscopy. For complex 1, the dna2− anion adopts μ1-η1:η1 chelating bidentate mode to coordinate with one Zn(ii) atom and π–π stacking interactions are formed between the L ligands. For complex 2, glu2− anions connect Zn(ii) atoms to form a wavy two-dimensional layer, and the L ligands are attached on two sides of the two-dimensional layer. [ABSTRACT FROM AUTHOR]