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Materials (Basel, Switzerland) Jun 2024The synergy of adsorption and photocatalysis is a good method to remove organic pollutants in wastewater. In recent decades, persistent photocatalysis has gained...
The synergy of adsorption and photocatalysis is a good method to remove organic pollutants in wastewater. In recent decades, persistent photocatalysis has gained considerable interest for its ability to sustain the catalytic degradation of organic pollutants in the dark. Herein, we report three different TiO nanomaterials to remove tetracycline hydrochloride (TCH) in solution. We found that the removal ability of TiO, Ni-TiO, and Ag/Ni-TiO is 8.8 mg/g, 13.9 mg/g and 23.4 mg/g, respectively, when the initial concentration of TCH is 50 mg/L. Chemical adsorption could be the rate-determining step in the TCH adsorption process. Moreover, Ag nanoparticles dispersed on Ni doped TiO surface act as traps to capture photo-generated electrons upon illumination with indoor light. The holes in Ag/Ni-TiO serve as critical oxidative species in TCH degradation under dark conditions. This work provides new insights into the design of persistent photocatalysts that can be activated by weak illumination and degrade organic pollutants in wastewater after sunset.
PubMed: 38930299
DOI: 10.3390/ma17122930 -
Materials (Basel, Switzerland) Jun 2024A solvent-free method was proposed for the synthesis of hexaimidazolecobalt(II) nitrate and perchlorate complexes-[Co(CHN)](NO) and [Co(CHN)](ClO)-by adding cobalt salts...
A solvent-free method was proposed for the synthesis of hexaimidazolecobalt(II) nitrate and perchlorate complexes-[Co(CHN)](NO) and [Co(CHN)](ClO)-by adding cobalt salts to melted imidazole. The composition, charge state of the metal, and the structure of the resulting complexes were confirmed by elemental analysis, XPS, IR spectroscopy, and XRD. The study of the thermochemical properties of the synthesized complexes showed that [Co(CHN)](NO) and [Co(CHN)](ClO) are thermally stable up to 150 and 170 °C, respectively. When the critical temperature of thermal decomposition is reached, oxidative two-stage gasification is observed. In this case, the organic component of the [Co(CHN)](NO) complex undergoes almost complete gasification to form CoO with a slight admixture of CoO, which makes it attractive as a component of gas-generation compositions, like airbags.
PubMed: 38930279
DOI: 10.3390/ma17122911 -
Materials (Basel, Switzerland) Jun 2024In the present work, magnesium oxide (MgO) and lead oxide (PbO) nanoparticles were prepared by the co-precipitation method. Their structural parameters and morphology...
In the present work, magnesium oxide (MgO) and lead oxide (PbO) nanoparticles were prepared by the co-precipitation method. Their structural parameters and morphology were investigated using XRD, HRTEM, and FTIR. The formation of the phases was seen to have small average crystallite sizes and an orthorhombic crystal structure for both MgO and PbO nanoparticles. The results of HR-TEM showed irregularly shaped nanoparticles: quasi-spherical or rod-like shapes and spherical-like shapes for MgO and PbO nanoparticles, respectively. The produced nanoparticles' size using X-ray diffraction analysis was found to be 17 nm and 41 nm for MgO and PbO nanoparticles, respectively. On the other hand, it was observed from the calculations that the optical band gap obeys an indirect allowed transition. The calculated values of the band gap were 4.52 and 4.28 eV for MgO and PbO NPs, respectively. The MB was extracted from the wastewater using the prepared composites via absorption. Using a variety of kinetic models, the adsorptions were examined. Out of all the particles, it was discovered that the composites were best. Furthermore, of the models currently under consideration, the pseudo-second-order model best fit the degradation mechanism. The resultant composites could be beneficial for degrading specific organic dyes for water purification, as well as applications needing a wider optical band gap.
PubMed: 38930259
DOI: 10.3390/ma17122890 -
Antioxidants (Basel, Switzerland) Jun 2024Bertoni, a no-calorie natural sweetener, contains a plethora of polyphenols that exert antioxidant properties with potential medicinal significance. Due to the variety... (Review)
Review
Bertoni, a no-calorie natural sweetener, contains a plethora of polyphenols that exert antioxidant properties with potential medicinal significance. Due to the variety of functional groups, polyphenols exhibit varying solubility depending on the nature of the extraction solvents (water, organic, or their mixtures, defined further on as hydroalcoholic extracts). In the present study, we performed a systematic review, following PRISMA guidelines, and meta-analysis, synthesizing all available data from 45 articles encompassing 250 different studies. Our results showed that the total phenolic content (TPC) of hydroalcoholic and aqueous extracts presents higher values (64.77 and 63.73 mg GAE/g) compared to organic extracts (33.39). Total flavonoid content (TFC) was also higher in aqueous and hydroalcoholic extracts; meta-regression analysis revealed that outcomes in different measuring units (mg QE/g, mg CE/g, and mg RUE/g) do not present statistically significant differences and can be synthesized in meta-analysis. Using meta-regression analysis, we showed that outcomes from the chemical-based ABTS, FRAP, and ORAC antioxidant assays for the same extract type can be combined in meta-analysis because they do not differ statistically significantly. Meta-analysis of ABTS, FRAP, and ORAC assays outcomes revealed that the antioxidant activity profile of various extract types follows that of their phenolic and flavonoid content. Using regression meta-analysis, we also presented that outcomes from SOD, CAT, and POX enzymatic antioxidant assays are independent of the assay type (-value = 0.905) and can be combined. Our study constitutes the first effort to quantitatively and statistically synthesize the research results of individual studies using all methods measuring the antioxidant activity of stevia leaf extracts. Our results, in light of evidence-based practice, uncover the need for a broadly accepted, unified, methodological strategy to perform antioxidant tests, and offer documentation that the use of ethanol:water 1:1 mixtures or pure water can more efficiently extract stevia antioxidant compounds.
PubMed: 38929131
DOI: 10.3390/antiox13060692 -
International Journal of Molecular... Jun 2024The oxidative esterification of aldehydes under mild conditions remains a significant challenge. This study introduces a unique defective UiO-66 to achieve gold...
The oxidative esterification of aldehydes under mild conditions remains a significant challenge. This study introduces a unique defective UiO-66 to achieve gold nanoclusters (AuNCs) for efficient aldehyde oxidation under mild conditions. The construction and characterization of these materials are thoroughly investigated by techniques of XRD, SEM and TEM images, FT-IR, Raman, and XPS spectrum, emphasizing the unique microporous in defective UiO-66 are conducive to the fabrication of AuNCs. The catalytic performance of the prepared materials in aldehyde oxidation reactions is systematically evaluated, demonstrating the remarkable efficiency of dispersed Au@UiO-66-25 with high-content (9.09 wt%) Au-loading and ultra-small size (~2.7 nm). Moreover, mechanistic insights into the catalytic process under mild conditions (70 °C for 1 h) are provided, elucidating the determination of defective UiO-66 in the confined fabrication of AuNCs and subsequent furfural adsorption, which underlie the principles governing the observed enhancements. This study establishes the groundwork for the synthesis of highly dispersed and catalytically active metal nanoparticles using defective MOFs as a platform, advancing the catalytic esterification reaction of furfural to the next level.
Topics: Gold; Metal Nanoparticles; Oxidation-Reduction; Aldehydes; Catalysis; Metal-Organic Frameworks; Porosity; Esterification; Spectroscopy, Fourier Transform Infrared
PubMed: 38928488
DOI: 10.3390/ijms25126779 -
International Journal of Molecular... Jun 2024In environmental chemistry, photocatalysts for eliminating organic contaminants in water have gained significant interest. Our study introduces a unique heterostructure...
In environmental chemistry, photocatalysts for eliminating organic contaminants in water have gained significant interest. Our study introduces a unique heterostructure combining MIL-101(Cr) and bismuth oxyiodide (BiOI). We evaluated this nanostructure's efficiency in adsorbing and degrading tetracycline (TC) under visible light. The BiOI@MIL-101(Cr) composite, with a surface area of 637 m/g, prevents self-aggregation seen in its components, enhancing visible light absorption. Its photocatalytic efficiency surpassed BiOI and MIL-101(Cr) by 33.4 and 9.2 times, respectively. Comprehensive analyses, including scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirmed the successful formation of the heterostructure with defined morphological characteristics. BET analysis demonstrated its high surface area, while X-ray diffraction (XRD) confirmed its crystallinity. Electron spin resonance (ESR) tests showed significant generation of reactive oxygen species (ROS) like h and·•O under light, crucial for TC degradation. The material maintained exceptional durability over five cycles. Density functional theory (DFT) simulations and empirical investigations revealed a type I heterojunction between BiOI and MIL-101(Cr), facilitating efficient electron-hole pair separation. This study underscores the superior photocatalytic activity and stability of BiOI@MIL-101(Cr), offering insights into designing innovative photocatalysts for water purification.
Topics: Metal-Organic Frameworks; Bismuth; Catalysis; Tetracycline; Light; Water Pollutants, Chemical; Water Purification; Reactive Oxygen Species; Adsorption; Photochemical Processes
PubMed: 38928465
DOI: 10.3390/ijms25126759 -
Photodegradation of a Broad-Spectrum Antibiotic Azithromycin Using HO under Ultraviolet Irradiation.International Journal of Molecular... Jun 2024The photodegradation of azithromycin present was carried out in water using HO under UV irradiation. The reaction variables considered in this study were the amount of...
The photodegradation of azithromycin present was carried out in water using HO under UV irradiation. The reaction variables considered in this study were the amount of HO solution and the initial concentration of azithromycin to evaluate the performance of the photodegradation process. The azithromycin degradation was not observed in the dark during stirring for 20 min. The study showed an efficient photodegradation of azithromycin using HO as an oxidant in the presence of UV irradiation. The azithromycin degradation was altered significantly by the pH of the irradiated solution. The degradation was low at an acidic pH and showed an increasing trend as the pH changed to basic. The azithromycin degradation increased with a higher amount (higher concentration) of HO. The degradation of azithromycin decreased with a higher concentration of azithromycin in the reacting solution. The highest degradation of AZT was achieved in 1 h using a 1.0 ppm AZT solution containing 3 mL of HO. The experimental data obtained were well-fitted to zero-order reaction kinetics. The results of this study were found quite excellent. They showed 100% degradation in 1 h when compared with those reported in the literature, both with photocatalysis using nanomaterials and photolysis using light irradiation and/or HO. The UV/HO system was found to be quite efficient for the photodegradation of azithromycin, and this system can be applied to degrade other organic pollutants present in industrial wastewater.
Topics: Azithromycin; Hydrogen Peroxide; Ultraviolet Rays; Photolysis; Anti-Bacterial Agents; Hydrogen-Ion Concentration; Water Pollutants, Chemical; Kinetics
PubMed: 38928406
DOI: 10.3390/ijms25126702 -
International Journal of Molecular... Jun 2024Ibogaine is an organic indole alkaloid that is used in alternative medicine to combat addiction. Numerous cases of life-threatening complications and sudden deaths...
Ibogaine is an organic indole alkaloid that is used in alternative medicine to combat addiction. Numerous cases of life-threatening complications and sudden deaths associated with ibogaine use have been reported, and it has been hypothesized that the adverse effects are related to ibogaine's tendency to induce cardiac arrhythmias. Considering that the bioavailability of ibogaine and its primary metabolite noribogaine is two to three times higher in female rats than in male rats, we here investigated the effect of a single oral dose (1 or 20 mg/kg) of ibogaine on cardiac histopathology and oxidative/antioxidant balance. Our results show that ibogaine induced dose-dependent cardiotoxic necrosis 6 and 24 h after treatment and that this necrosis was not a consequence of inflammation. In addition, no consistent dose- and time-dependent changes in antioxidant defense or indicators of oxidative damage were observed. The results of this study may contribute to a better understanding of ibogaine-induced cardiotoxicity, which is one of the main side effects of ibogaine use in humans and is often fatal. Nevertheless, based on this experiment, it is not possible to draw a definitive conclusion regarding the role of redox processes or oxidative stress in the occurrence of cardiotoxic necrosis after ibogaine administration.
Topics: Animals; Ibogaine; Necrosis; Rats; Oxidation-Reduction; Oxidative Stress; Male; Female; Cardiotoxicity; Antioxidants; Myocardium; Rats, Wistar
PubMed: 38928231
DOI: 10.3390/ijms25126527 -
International Journal of Molecular... Jun 2024The electrophilic activation of various substrates via double or even triple protonation in superacidic media enables reactions with extremely weak nucleophiles. Despite...
The electrophilic activation of various substrates via double or even triple protonation in superacidic media enables reactions with extremely weak nucleophiles. Despite the significant progress in this area, the utility of organophosphorus compounds as superelectrophiles still remains limited. Additionally, the most common superacids require a special care due to their high toxicity, exceptional corrosiveness and moisture sensitivity. Herein, we report the first successful application of the "Brønsted acid assisted Brønsted acid" concept for the superelectrophilic activation of 2-hydroxybenzo[][1,2]oxaphosphinine 2-oxides (phosphacoumarins). The pivotal role is attributed to the tendency of the phosphoryl moiety to form hydrogen-bonded complexes, which enables the formation of dicationic species and increases the electrophilicity of the phosphacoumarin. This unmasks the reactivity of phosphacoumarins towards non-activated aromatics, while requiring only relatively non-benign trifluoroacetic acid as the reaction medium.
Topics: Catalysis; Organophosphorus Compounds; Hydrogen Bonding; Acids; Molecular Structure
PubMed: 38928034
DOI: 10.3390/ijms25126327 -
Biomolecules Jun 2024Among the grapes, is a winegrape variety characterised by a high content of free and glycosylated monoterpenoids, which gives wines very intense notes of ripe fruit...
Among the grapes, is a winegrape variety characterised by a high content of free and glycosylated monoterpenoids, which gives wines very intense notes of ripe fruit and flowers. The aromatic bouquet of is strongly influenced by the high concentration of linalool, geraniol, linalool oxides, limonene, α-terpineol, citronellol, hotrienol, diendiols, -8-hydroxy linalool, geranic acid and myrcene, that give citrus, rose, and peach notes. Except for quali-quantitative analysis, no investigations regarding the isotopic values of the target volatile compounds in grapes and wines are documented in the literature. Nevertheless, the analysis of the stable isotope ratio represents a modern and powerful tool used by the laboratories responsible for official consumer protection, for food quality and genuineness assessment. To this aim, the aromatic compounds extracted from grapes and wine were analysed both by GC-MS/MS, to define the aroma profiles, and by GC-C/Py-IRMS, for a preliminary isotope compound-specific investigation. Seventeen samples of grapes were collected during the harvest season in 2021 from two Italian regions renowned for the cultivation of this aromatic variety, Trentino Alto Adige and Veneto, and the corresponding wines were produced at micro-winery scale. The GC-MS/MS analysis confirmed the presence of the typical terpenoids both in glycosylated and free forms, responsible for the characteristic aroma of the variety, while the compound-specific isotope ratio analysis allowed us to determine the carbon (δC) and hydrogen (δH) isotopic signatures of the major volatile compounds for the first time.
Topics: Volatile Organic Compounds; Gas Chromatography-Mass Spectrometry; Wine; Vitis; Tandem Mass Spectrometry; Carbon Isotopes; Fruit; Odorants
PubMed: 38927113
DOI: 10.3390/biom14060710