CO Groups Research Articles

Carbon dots based cascading nanozymes mitigate phytotoxicity in lettuces under imidacloprid stress

Improper pesticide use induces oxidative stress and disrupts detoxification systems in plants. We synthesized CDs with cascading nanozyme activities to mitigate phytotoxicity in lettuces under imidacloprid (IMI) stress. CDs exhibit superoxide dismutase-like (SOD-like) and peroxidase-like (POD-like) activities. Surface modifications and analysis of CDs, the SOD-like activity relies on the -NH2, -COOH, and -OH groups for binding superoxide anions (O2•-), while POD-like activity depends on -COOH and CO groups, also, CO group provides π-system and the electron-deficient structure for electron transfer. Practically, under IMI stress, CDs strengthen multiple defense systems in lettuces, reducing levels of reactive oxygen toxicity (O2•-, H2O2, and MDA, by 26.77 %, 48.52 %, and 13.10 %, respectively). Meanwhile, CDs upregulate detoxification gene expression, resulting in a 42.74 % reduction in IMI residue in lettuces. Moreover, the acceptable daily intake of IMI in lettuces treated with CDs was less than 18.0 % of the reference dose, even at high-concentration IMI.

Self-adaptive carbon nanozyme regulation of ROS balance for bacteria-infected wound therapy

Nanozymes sterilizing drug-resistant (DR) bacteria by generating reactive oxygen species (ROS) have emerged as a promising approach for treating infected wounds. However, designing biocompatible adaptive ROS balance therapeutic platform for DR bacteria-infected wounds remains a great challenge. Herein, biocompatible lignin-based carbon dot nanomaterials (LCDs-OA) with more CO and COOH functional groups on the surface were prepared by hydrothermal organic acid co-processing and used as a dual enzyme-like active nanozyme for the therapy of wounds infected by DR bacteria. Experimental and theoretical calculations demonstrated that the CO and COOH functional groups in LCDs-OA have site-switching roles in the dual enzyme-like activity, which can balance reactive oxygen species (ROS) according to the changes in microenvironmental pH at the wound site, and realize the adaptive regulation of ROS generation for bactericidal and ROS scavenging for healing. Furthermore, the performance differences between different organic acid treatments were investigated and an adaptive ROS balance therapeutic platform (LCDs-OA@CaO2) was constructed to overcome the major limitation in treating DR bacterial infected wounds. The system achieved >99.6 % in vitro antimicrobial efficiency against DR bacteria and was highly biocompatible while effectively reducing oxidative damage to normal tissues, resulting in satisfactory therapeutic results in repairing wounds infected with DR bacteria.

A growing-finishing diet formulated to reduce the soybean meal does not compromise the growth performance, health, behaviour and gut health of Italian heavy pigs

Soy contributes to the environmental impact of Italian pork production. This study aimed to evaluate the effect of a reduced soybean meal (SBM) and crude protein (CP) finishing diet on growth performance, health, behaviour and gut health of Italian heavy pigs. 1920 pigs (35.6 kg body weight; (BW)) balanced by sex and BW were assigned to the control diet (CO), or the treated diet (TRT) formulated by reducing SBM by 31%, 67% and 69% (replaced by pea and sunflower meal) in 3 feeding phases, respectively, and 1.2% CP in the third phase. 251 pigs were individually weighed at d11, d94 and d181. Feed intake (FI), behavioural indices and air gases at pen-level were monitored monthly. Faecal samples (20/pigs/group) for microbiota, ammonia and volatile fatty acids (VFAs) and hair for stress biomarkers were collected. Diet did not affect final BW, faecal ammonia, cortisol and dehydroepiandrosterone. From d11–d94, the CO group had higher gain to feed (G:F) (p = .007), favourable faecal VFAs profile and a lower environmental ammonia (p < .0001). From d10–d181, the TRT diet increased the ADG (p = .04) and G:F (p = .01), reduced FI (p < .0001) and the lesions score index at d102 (p = .03) and promoted Methanobrevibacter (d94; padj. = 0.013) and Clostridium sensu stricto (d181; padj. = 0.001). Overall, the TRT diet combined with the stress of the transport and acclimatisation to the farm may limit the growth of pigs in the initial period, but it can increase their growth in the long term. Concluding, replacing 56% of SBM with sustainable alternatives seems promising for heavy pig.

Effect of Porphyromonas gingivalis Infection on Healing of Skeletal Muscle Injury: An In Vivo Study

Background/Objectives: Porphyromonas gingivalis infection has been associated with various systemic diseases and may cause delayed healing of muscle injury. However, the relationship between muscle injury healing and P. gingivalis infection remains unclear. Our hypothesis was that P. gingivalis infection delays the healing of muscle injuries. Methods: Fifty-six 8-week-old male Wistar rats were randomly divided into two groups: sonicated P. gingivalis was intraperitoneally administered in one group (PG group), whereas saline was administered in the other group (CO group). Skeletal muscle injury was induced via cardiotoxin injections in all animals. The cross-sectional area of regenerating muscle cells was evaluated by haematoxylin–eosin staining, and the degree of muscle fibrosis was evaluated by Masson’s trichrome staining. The expression of paired box protein (Pax7) and myoblast determination protein (MyoD) and the identified stages of myocyte regeneration were analysed by immunohistochemical staining. Motion analysis was performed during walking. Results: The cross-sectional area of muscle cells was significantly smaller in the PG group on days 7 and 14 post-injury than in the CO group. The Pax7+/MyoD− ratio was significantly lower in the PG group on day 1 post-injury than in the CO group. Motion analysis of treadmill walking showed that the PG group had a lower minimum calcaneal height on days 3 and 7 post-injury than the CO group. Conclusions: This study suggests that administration of sonicated P. gingivalis in rats can delay the healing process of muscle injury. Further research is needed to understand this mechanism of delay of P. gingivalis.

Efficient photocatalytic degradation of chloramphenicol from contaminated water over rGO@MoS2 nanocomposites

Antibiotics-based effluents pose a severe threat to the natural ecosystem by acting as reservoirs for the growth of drug-resistant bacteria if untreated. Herein, a facile and scalable approach was developed to engineer photocatalysts associating reduced graphene oxide (rGO) and molybdenum disulfide (rGO@MoS2) that were used for the degradation of chloramphenicol (CAP) from contaminated water under UV-light. The hydrothermally produced rGO@MoS2 catalysts contain CO, COH, and COC functional groups that contribute to the binding of CAP onto their surface. The rGO surface modification with MoS2 layers offers a high surface area for light absorption. Results show that the rGO@MoS2 catalyst (1:1 w/w) exhibits the highest degradation efficiency (DE) of 86 % within 180 min of light exposure at neutral pH. Further, the kinetic modelling studies for CAP degradation by rGO@MoS2 1:1 showed high linearity with pseudo-first order kinetics (R2 ∼ 0.9). The isotherm modelling studies correspond to Langmuir isotherm (R2 ∼ 0.99), suggesting monolayer-type interaction of CAP with the photocatalyst surface during photodegradation. Furthermore, the mechanism of degradation elucidated using scavenging experiments showed the involvement of both holes (h+) and electrons (e−) that contribute to the degradation of CAP by generating reactive oxygen species (ROS) like OH● and O2●− radicals. The applicability of the rGO@MoS2 photocatalyst towards the degradation of CAP was tested in Ganga water, wherein a similar ∼86 % CAP removal was observed. Furthermore, the photocatalyst was found to be stable and could be reused five times. Overall, these findings demonstrate the usefulness of the rGO@MoS2 1:1 composite as an efficient photocatalyst that can be used for the degradation of harmful organic pollutants from water bodies to provide a safer and cleaner environment.

Efficient photocatalytic degradation of microplastics by constructing a novel Z-scheme Fe-doped BiO2−x/BiOI heterojunction with full-spectrum response: Mechanistic insights and theory calculations

Recently, microplastics (MPs) have garnered significant attention as a challenging emerging pollutant to address. Here, a full-spectrum light-driven Fe-doping BiO2−x/BiOI (FBI) Z-scheme heterojunction was constructed for efficiently degrading MPs in waters. Compared with BiO2−x, Fe doping BiO2−x, and BiOI, the optimal photocatalyst (40-FBI) can cause deep cracks in the polyethylene terephthalate (PET) within 10 h under the irradiation of full-spectrum light. Meanwhile, FT-IR characterization revealed that the absorption peak intensities of the C-O group, CO group, -CH stretching vibration, and -OH group on the MPs surface gradually increased with degradation time. A series of experiments and theory calculations revealed that the introduction of Fe creates impurity levels, accelerating the separation of photo-generated carriers and reducing the work function of BiO2−x, thereby enhancing the transport of photo-generated carriers between Z-scheme heterojunctions. This study offers a valuable idea for designing an efficient photocatalyst by simultaneously introducing ion doping and constructing heterojunctions for enhancing MPs degradation.

Microplastics interactions and transformations during in vitro digestion with milk

Despite increasing awareness of microplastic contamination in food, the specific interactions and transformations of microplastics during digestion remain poorly understood. The study investigates the behavior of microplastics during in vitro digestion processes and their interaction with components of milk. The in vitro digestion studies are conducted to study the changes in microplastics in simulated digestive fluids, with and without milk. The study revealed that microplastics undergo significant changes in size, surface morphology, and chemical properties when subjected to digestion with and without milk. Notably, microplastics digested with milk exhibited a 15–25 % increase in aggregation due to protein corona formation, enhancing their potential for interactions within biological systems. FTIR analysis revealed the formation of OH and CO groups in digested microplastics, indicating hydrolysis and structural changes. The stronger peaks in the 1630–1650 cm−1 range suggest significant adsorption of milk proteins, highlighting the complex interactions during digestion. Additionally, the chemicals and additives leached from microplastics into digesta raising the concerns about their potential health effects. The study emphasizes the necessity for additional research and regulatory measures to address the risks associated with microplastic contamination in food.

OBTAINING AN ACTIVE INGREDIENT FOR COTTON SEED TREATMENT BASED ON METHYLENDIUREA AND PARAAMINOBENZOIC ACID AND STUDYING ITS PHYSICOCHEMICAL CHARACTERISTICS

Seed treatment is the main method of protecting plants from infectious diseases. The article presents data on the production of a double compound based on methylene diurea and paraaminobenzoic acid and the study of its physicochemical characteristics. The chemical interaction in the three-component water-salt system methylenediurea (MDU) – para-aminobenzoic acid (PABA) – water was studied using the isothermal method of physicochemical analysis. The crystallization region of the new binary compound, the active substance, was established at a molar ratio MDU: PABA = 1:2. The formation of the double compound is confirmed by X-ray phase and IR spectroscopic methods of analysis. From the obtained X-ray phase analysis data, it follows that the reference lines of the double compound and their intensity differ from the X-ray patterns of the initial components. The IR spectra of MDM and PABA are characterized by intense absorption in the region of 3500-3390 cm-1 , 2000-500 cm-1 and 3500-3345 cm-1 , 1800-500 cm-1 , respectively. In the IR spectra of the new double compound MDM•2PABA, the absorption intensity in the region of 1800-500 cm-1 increases. A decrease in the absorption region of the stretching vibration of CO groups from 1626, 1626.3 cm-1 to 1612 cm-1 is observed in the case of the double compound MDM•2PABA. The results of the studies indicate the formation of a new compound. It is shown that the double compound has low hygroscopicity under summer, autumn, spring and winter storage conditions, high swelling and moisture capacity, and low solubility.

ALPHA-MANGOSTIN POTENCY TO IMPROVE RENAL FUNCTION AND HISTOPATHOLOGICAL IMAGES IN HIGH-FAT DIET RATS

This study aimed to study whether alpha-mangostin could protect the kidneys of high-fat diet rats using the creatinine serum level and histopathological changes as parameters. The in vivo experimental study with a completely randomized design used 30 male Sprague Dawley rats. After 7 days of adaptation, they were randomly divided into six treatment groups, each with five replications. The study was done for four weeks: NC group (given standard pellet without treatment for four weeks), five other groups were given a high-fat diet for four weeks, and at the last two weeks were added with aquadest, corn oil, alpha-mangostin dose-1, alpha-mangostin dose-2, and simvastatin, namely PTL, CO, D1, D2, and Sim group. Creatinine level was examined at the end of week 2 and week 4; the difference percentage was analyzed using ANOVA/Kruskal Wallis (α=0.05) and continued with Duncan/Mann Whitney. It was shown that creatinine level decreased in D1/D2 = PTL mice (p&gt;0,05); kidney histopathological image in D1 was better than PTL (p&lt;0,05). It was concluded that the alpha-mangostin kidney protection effect was not yet visible according to creatinine level, but it was visible according to histopathological image; further studies are needed.

Efficient adsorption and selective separation of high value-added chemicals from simulated expired energy drinks by metal-organic frameworks

Expired energy drinks contain a certain amount of high-value chemicals, such as caffeine, that possess biological activity. The recovery and recycling of these valuable chemicals plays a crucial role in promoting the achievement of carbon emission reduction goals. In this work, 11 kinds of water-stable MOFs with different pore channel structure were synthesized and used for the first time to adsorb caffeine, nicotinic acid, or taurine from water. It has been found that the size effect of the topological structure of MOF adsorbents is the fundamental factor governing their adsorption performance. The optimized adsorbent UiO-67 exhibits excellent adsorption performance for caffeine and nicotinic acid, with respective adsorption capacities of 830 mg/g and 583 mg/g. The investigated MOF has a very low adsorption capacity for taurine (48 mg/g); therefore, selective separation of caffeine/taurine and nicotinic acid/taurine was achieved. The adsorption process can be accurately described by both the Langmuir model and pseudo-second-order model. Adsorption mechanism reveals that the main driving forces of the adsorption process are π-π interaction between UiO-67 and CN in caffeine, as well as hydrogen bonding interactions between the N atom of caffeine’s two CO groups and μ-OH of UiO-67.

Synthesis and characterization of rhenium and Technetium-99 m tricarbonyl and dicarbonyl complexes with quinaldic acid and Arsenic/Phosphorus derivatives

The synthesis and characterization of neutral tricarbonyl fac-[Re/99mTc(quin)(X)(CO)3] and dicarbonyl cis–trans-[Re/99mTc(quin)(X)2(CO)2] mixed ligand complexes with quinaldic acid (quin) as the bidentate ligand and trimethoxyphosphine [P(OCH3)3], tris(hydroxymethyl)-phosphine [P(CH2OH)3], triphenylphosphine (PPh3), and triphenylarsine (AsPh3) as the monodentate ligands (X) is described. The synthesis of the [2 + 1] tricarbonyl complexes proceeds by displacement of the water molecule of the fac-[Re/99mTc(quin)(H2O)(CO)3] by the monodentate ligand. Interestingly, the synthesis of the [2 + 1 + 1] dicarbonyl complexes was achieved only for PPh3 after replacing the CO group trans to PPh3 with a second PPh3 molecule. The latter complex was also obtained by refluxing quinaldic acid with the trans-mer-[Re(PPh3)2(Cl)(CO)3] precursor in toluene. Rhenium complexes were prepared in satisfactory yields and fully characterized. At the technetium-99 m level, complexes were produced in high radiochemical yields and characterized by comparative chromatographic analysis using the analogous rhenium complexes. Complexes have shown varying stability against transchelation by cysteine and histidine in agreement with the decreasing σ-donating capacity of the monodentate ligand (P(OCH3)3 > P(CH2OH)3 > PPh3 > AsPh3. The stable complexes with PPh3 showed high lipophilicity (LogP 2.90 and 3.10, respectively) due to the lipophilic nature of the monodentate ligands. The σ-donor and π-acceptor capacity of the monodentate ligand strongly influences the formation and stability of the complexes, and these characteristics should be considered before choosing the appropriate ligand for radiopharmaceuticals design.

Low-energy argon ion beam irradiation for the surface modification and reduction of graphene oxide: Insights from XPS

Developing environmentally friendly methods for reducing graphene oxide (GO) is essential. This study investigates the surface modification and reduction of GO films using 200 eV argon ion (Ar+) beam irradiation. X-ray Photoelectron Spectroscopy (XPS) analysis reveals significant chemical changes on the GO surface. GO was irradiated with a 200 eV Ar+beam for varying times (0–80 s). XPS survey spectra showed the presence of carbon and oxygen, with an increasing carbon atomic percentage over time. High-resolution XPS spectra of C 1s revealed peaks corresponding to sp2, C–OH, O–C–O, CO, and O–CO bonds. In the O 1s spectra, CO, O–C–O, and C–OH groups were observed. Upon irradiation, the CO peak consistently decreased, the O–C–O peak fluctuated, and the C–OH peak increased, indicating effective reduction of CO groups, dynamic changes in O–C–O functionalities, and the formation of additional C–OH groups. The C/O ratio increased from ∼2.4 to 2.7, underscoring the reduction process and enhanced carbon content. This method proves to be an efficient approach for producing reduced graphene oxide (rGO) with improved properties for advanced applications.

Dietary Effects of Black-Oat-Rich Polyphenols on Production Traits, Metabolic Profile, Antioxidative Status, and Carcass Quality of Fattening Lambs

The study aimed to establish the dietary effects of black oat rich in polyphenols on the production traits, metabolic profile, antioxidant status, and carcass quality of fattening lambs, after weaning. In the BO group, in the feed mixture, common oats replaced the black oat compared to the CO group. The research comprehensively investigated production indicators, blood metabolic profile, antioxidant status, and lamb carcass quality. No significant differences were found in the fattening or slaughter characteristics of lamb carcasses, except for lower pH1 values in BO lamb carcasses. Significant increases in RBC, HCT, and MCV levels as well as TP, ALB, and GLOB concentrations and GPx and SOD activities in the blood of BO lambs were found. The glucose and EOS content as well as the activity of the enzymes ALT and ALP were significantly lower in the blood of the BO group than in the CO group. In the liver, the DPPH activity was significantly higher in the BO lambs compared to the CO lambs. The observed changes in glucose, protein metabolism, and antioxidant status in the blood and tissues of lambs indicate that the use of polyphenol-rich black oats in the diet of lambs under stress conditions is justified.

Significant performance enhancement of Zn-ion hybrid supercapacitors based on microwave-assisted pyrolyzed active carbon via synergistic effect of NaHCO3 activation and CNT networks

Zinc-ion hybrid supercapacitors (ZIHSCs) represents a promising technological approach for large-scale energy storage with the combined advantages of supercapacitors and zinc-ion batteries. Unfortunately, it is still challengeable to quickly fabricate low-cost, high-performance carbonaceous cathode materials at relatively low temperature. To address such issues, herein, taking waste Eucommia ulmoides Oliver (EUO) wood as an example, we present a novel microwave-assisted carbonization (MWC) approach at relatively low temperature to quickly prepare active carbon, and we present a synergistic strategy to significantly enhance the electrochemical performance by introducing sodium bicarbonate activation (SA) and constructing conductive carbon nanotubes (CNT) networks. The MWC-SA@CNT hybrid exhibits outstanding specific capacitance of 344.2 F/g at 0.2 A/g within three-electrode system, much better than conventional high-temperature pyrolyzed AC, MWC carbon, and MWC-SA carbon. The superior performance of MWC-SA@CNT can be attributed to the synergistic effect of its large specific surface area of 1102.7 m2/g, high mesoporous percentage of 53.5%, and rich –OH and CO groups due to microwave-assisted carbonization and sodium bicarbonate activation, and rich electron transport paths due to the presence of CNT networks. Furthermore, ZIHSCs assembled by MWC-SA@CNT cathode could delivers impressive performance with excellent capacity (194.37 mA h/g at current density of 1 A/g), energy density (142.30 Wh/kg), and durability (capacitance retention rate of 97.65% after 5000 cycles). This work offers a rapid and low-temperature method for preparing wood-based active carbon with rich nanopores and strong conductivity to improve performance of Zinc ion storage.

Trinuclear and Tetranuclear Ruthenium Carbonyl Nitrosyls: Oxidation of a Carbonyl Ligand by an Adjacent Nitrosyl Ligand.

Trinuclear and tetranuclear ruthenium carbonyls of the types Ru3(CO)n(NO)2, Ru3(N)(CO)n(NO), Ru3(N)2(CO)n, Ru3(N)(CO)n(NCO), Ru3(CO)n(NCO)(NO), Ru4(N)(CO)n(NO), Ru4(N)(CO)n(NCO), and Ru4(N)2(CO)n related to species observed experimentally in the chemistry of Ru3(CO)10(µ-NO)2 have been investigated using density functional theory. In all cases, the experimentally observed structures have been found to be low-energy structures. The low-energy trinuclear structures typically have a central strongly bent Ru-Ru-Ru chain with terminal CO groups and bridging nitrosyl, isocyanate, and/or nitride ligands across the end of the chain. The low-energy tetranuclear structures typically have a central Ru4N unit with terminal CO groups and a non-bonded pair of ruthenium atoms bridged by a nitrosyl or isocyanate group.

Novel poly(2-ethyl-2-oxazoline) and poly(diallyldimethylammonium chloride) polymer functionalized montmorillonite: Physicochemical aspects and near-IR study of hydration properties

The novel functionalized montmorillonites (Mts) with non-ionic poly(2-ethyl-2-oxazoline) (PEtOx) and cationic poly(diallyldimethylammonium) (PDDA) were created via an intercalation method with different loading ratio of both polymers. A comprehensive investigation into their physicochemical properties was conducted using Carbon analysis (CA), Powder X-ray diffraction (PXRD), Fourier-transform infrared spectroscopy (FTIR), Simultaneous thermal analysis (TGA/DSC) and BET-N2 adsorption analysis. The impact of hydration on PEtOx-Mts and PDDA-Mts was assessed through gravimetric analysis and near-infrared spectroscopy (NIR) spectroscopy. PXRD analysis revealed a significant increase in 001 diffraction of PDDA-Mt corresponding to a PDDA interlayer with a basal spacing ranging from 1.47 to 1.49 nm. Conversely, the basal spacing exceeding 2 nm for PEtOx suggested, that the PEtOx polymer was intercalated in a larger amount and packed in a less compact manner compared to PDDA. After modification of Na-Mt with PEtOx polymer, FTIR spectroscopy confirmed the presence of the carbonyl CO group (3265 and 1641 cm-1) and the stretching (2982, 2942 and 2883 cm-1) and bending (1480–1200 cm-1) vibrations of the CH2 and CH3 groups. The vibrations of CH groups were further verified following PDDA modification. NIR spectroscopy also confirmed the vibrational bands attributed to both modifiers after intercalation of PEtOx and PDDA. The results of BET-N2 adsorption revealed a significant decrease in the specific surface area (SSA) after intercalation with a non-ionic PEtOx polymer. On the contrary, in the case of saturation of Na-Mt with polycation PDDA, SSA increased slightly in two instances. TGA analysis confirmed greater weight loss for PEtOx-Mts compared to PDDA-Mts. Derivative thermogravimetry (DTG) revealed the release of physisorbed bound water around 100 °C, decomposition of the organic phase within the 250–550 °C range and dehydroxylation of OH groups around 550–800 °C in both cases. The results obtained from the gravimetry and NIR analysis indicated a greater hydrophobic nature for PEtOx-Mts compared to PDDA-Mts. These findings hold substantial potential for enhancing the properties of novel organo-montmorillonites, thereby facilitating their application as adsorbents for pollutants, surface coatings, biodegradable materials, fillers in polymer nanocomposites, drug carriers, anticancer agents and various other significant applications.

Functionalization of MXene using iota-carrageenan, maleic anhydride, and N,N′-methylene bis-acrylamide for high-performance removal of thorium (IV), uranium (IV), sulfamethoxazole, and levofloxacin

An increasing quantity of pollutants has been discharged into the aquatic media, posing a serious hazard to public health. To address this issue, a new sorbent material, MXene@i.Carr@MaMb, was developed through the functionalization of the MXene surface using iota-carrageenan (i.Carr), maleic anhydride, and N, N′-methylene bis-acrylamide. This sorbent material was designed to remove thorium (Th (IV)) effectively, uranium (U (IV)), sulfamethoxazole (SMX), and levofloxacin (LEV) from wastewater. The MXene@i.Carr@MaMb composite incorporated significant functional groups, including OH, F, and O from MXene, oxygen and ester sulfate groups from iota-carrageenan (i.Carr), and OH, NH, and CO groups from N, N′-methylene bis-acrylamide, and maleic anhydride, which interacted with the UV (IV), Th (IV), SMX, and LEV pollutants through electrostatic interaction, complexation, and hydrogen bonding. MXene@i.Carr@MaMb composite exhibited excellent sorption capacities for Th (IV) (3.6 ± 0.03 mmol g−1), U (IV) (3.7 ± 0.09 mmol g−1), SMX (5.8 ± 0.03 mmol g−1), and LEV (5.9 ± 0.05 mmol g−1) at 323.15 K. The sorption kinetics and isotherms of radioactive metals and antibiotics can be well-described using pseudo-first-order kinetic models and Langmuir and Sips isothermal equations. This study presented a novel sorbent material for efficiently removing radioactive metals and antibiotics from wastewater.

Synthesis, structural characterization and in vitro digestion stability of a soluble soybean polysaccharide‑zinc chelate

The chelation reaction of soluble soybean polysaccharide (SSPS) with zinc was investigated. Using response surface methodology, the optimum parameters for SSPS-Zn synthesis were obtained: pH 5.3, SSPS-ZnCl2 mass ratio of 9.44:1, reaction temperature 50.44 °C, and reaction time 1.5 h, with the highest zinc content of 24.73 %. Compared with SSPS, SSPS-Zn increased in rhamnogalacturonan content and decreased in that of neutral monosaccharides (Fuc, Ara, Gal, Glu and Xyl). UV–vis spectra indicated that SSPS-Zn was lower than SSPS in protein content. FTIR spectra indicated that CO group of SSPS was bonded to Zn2+. X-ray diffraction spectra demonstrated that SSPS-Zn had higher crystallinity. Congo red reactions showed that SSPS possessed a triple-helix conformation while SSPS-Zn formed an irregular free-coiled conformation. EDX confirmed SSPS-Zn synthesis successfully. TGA curves exhibited that SSPS-Zn required higher temperature to undergo degradation. AFM revealed that SSPS-Zn was clustered while SSPS was filamentous. SEM micrographs showed the cracked fragments on the surface of SSPS-Zn. By in vitro simulation of gastrointestinal digestion, Zn2+ release reached 68.87 % after 2 h digestion. Consequently, the chelation of SSPS with zinc could change structure and provide a basis for research and application of novel zinc supplements.

Surface engineering and concentration-dependent emission activated flexible tunable fluorescence from lignin-based N-doped carbon dots

Achieving the flexible and tunable fluorescence of lignin-based N-doped carbon dots (LCDs) remains a win–win yet challenging strategy. In this study, combining the surface engineering and concentration regulation strategy enabled the flexible adjustment of LCDs fluorescence emission from blue to yellow regions (345 to 560 nm). The surface electron-donor –OH groups not only enhanced the photoluminescence quantum yield (PLQY) to 14.75 % but activated the spectral shift of reduced LCDs (RLCDs). These arose from the reinforced π-electron conjugation and generated new –OH-related extrinsic defects with elevating concentration. Conversely, the electron-withdrawing CO groups participated in the blue-to-green fluorescence modulation. Still, they drastically reduced the PLQY of oxidized LCDs (OLCDs) to 2.13 %, due to the larger particle size and more non-radiative transfer induced by CO groups. Based on these, CDs/PVA films and printed fluorescent patterns with multicolor fluorescence were realized for anti-counterfeiting, and the RLCDs@Al2O3 hybrid facilitated the precise fluorescence fingerprint tracking and recognition. This study provided a facile strategy for enriching and developing novel LCDs with flexible fluorescence for their advanced applications.

Hydrophobic and porous Fe-Pdb coordination framework structure supported Pt-Fe nanoparticles catalyst for enhanced chemoselective hydrogenation of cinnamaldehyde

The selective hydrogenation of cinnamaldehyde to cinnamyl alcohol has remained a ponding challenge due to competitive hydrogenation reactions between CC and CO groups. In this work, a hydrophobic and porous Fe and 3,3′-(pyridine-3,5-diyl)-dibenzoic acid coordination framework structure (Fe-Pdb(CFs)) was employed to support Pt-Fe nanoparticles and synthesize a high-performance Pt-Fe/Fe-Pdb(CFs) heterogeneous catalyst. The reactivity activity could be greatly improved by introducing electrophilic sites and enhancing the enrichment effect of Fe-Pdb(CFs) material. Thus, the optimal cinnamaldehyde conversion reached approximately 88.9%, with a better selectivity of 85.8% towards cinnamyl alcohol at 60°C.