Interaction Of Functional Groups Research Articles

Molecularly tailored bifunctional nano-overlayers for efficient and stable inverted perovskite solar cells

Triple cation perovskite solar cells (PSCs) have made remarkable progress in power conversion efficiency (PCE), which is also related to the interface regulation layers between the active layer and electron transport layer (ETL). The ionic nature of the perovskite lattice has enabled approaches to passivate molecular defects through the interaction of functional groups. Herein, a passivator OXD-7 is introduced as a modified layer to passivate surface defects and accelerate electron transfer. It has been observed that OXD-7 can alleviate the micro-strain of the perovskite thin films through intermolecular bonding, which suppresses the iodide vacancy on the perovskite surface. Additionally, the OXD-7 reduces the surface energy of the perovskite films and inhibits the formation of δ-FAPbI3 on the surface of perovskite film. Consequently, the resulting devices demonstrate improved fill factor and device stability. Under optimal fabrication conditions, triple cation mixed perovskite solar cells with an inverted structure achieve a PCE of 23.83%.

Biomass-based perovskite/graphene oxide composite for the removal of organic pollutants from wastewater

Water pollution is a critical issue that affects both human health and the environment. Biomass-based LaFeO3 is prepared by the microwave-assisted method using rice straw as a cellulose source. Then LaFeO3/graphene oxide (GO) composite is prepared by ultrasonication to facilitate the perovskite-GO binding. Raman and FTIR spectra of the prepared composite identify the presence of the perovskite, biochar, cellulose and GO oxide phases and proves the surface functional groups interactions. Transmission electron microscope image shows that the GO sheets are homogeneous covered with the perovskite nanoparticles. The adsorption performance of the LaFeO3/GO composite for the removal of methylene blue (MB) and congo red (CR) dyes from aqueous solution is optimized. Adsorption follows pseudo 2nd order kinetic model and Freundlich isotherm, with maximum adsorption capacities of 319.5 and 416.7 mg/g for MB and CR, respectively. These values are higher than those reported for magnetic GO composites, indicating the excellent adsorption ability of the proposed perovskite/GO composite. A thermodynamic study shows that the adsorption of MB is exothermic, while it is endothermic for CR and combines physisorption and chemisorption characteristics for both dyes. The proposed adsorbent shows a good performance in the presence of NaCl interferent, with the possibility of regeneration and efficient successive reuse.

Synthesis, characterization, and surface modification of degradable polar hydrophobic ionic polyurethane nanoparticles for the delivery of therapeutics to vascular tissue

Degradable polar hydrophobic ionic polyurethanes (D-PHI) are an emerging class of biomaterials with particular significance for blood-contacting applications due to their immunomodulatory effects and highly customizable block chemistry. In this manuscript, D-PHI polymer was formulated as a nanoparticle excipient for the first time by inverse emulsion polymerization. The nanoparticles were optimized with consideration of diameter, surface charge, size variability, and yield as a delivery vehicle for a custom vascular therapeutic peptide. A layer-by-layer (LBL) surface modification technique using poly-L-lysine was integrated within the nanoparticle design to optimize therapeutic loading efficiency. Solvent pH played a pivotal role in emulsion micelle formation, LBL polymer secondary structure, and the polymer functional group interactions critical for high therapeutic loading. The resulting nanoparticle platform met target size (200 ± 20 nm), polydispersity (<0.07), and storage stability standards, was nontoxic, and did not affect therapeutic peptide bioactivity in vitro. Surface-modified D-PHI nanoparticles can be reproducibly manufactured at low cost, generating a highly customizable excipient platform suitable for delivery of biomolecular therapeutics. These nanoparticles have potential applications in vascular drug delivery via localized infusion, drug eluting stents, and drug-coated angioplasty balloons. Statement of significanceNanoscale excipients have become critical in the delivery of many therapeutics to enhance drug stability and targeted biodistribution through careful design of nanoparticle composition, surface chemistry, and size. This manuscript describes the development of a nanoparticle excipient derived from an immunomodulatory degradable polar hydrophobic ionic polyurethane, in combination with a layer-by-layer surface modification approach utilizing poly-L-lysine, to transport a mimetic peptide targeting smooth muscle cell migration in vascular disease. The nanoparticle platform draws on the effect of pH to maximize drug loading and tailor particle properties. The low cost and easily reproducible system presents a highly customizable platform that can be adapted for therapeutic delivery across a wide range of clinical indications.

Efficient chromium remediation using eco-innovative biochar in a novel two-stage upflow fixed bed system

Chromium (Cr) pollution poses a significant environmental threat. This study addresses the highly toxic hexavalent form of chromium [Cr(VI)] by developing an innovative two-stage upflow fixed-bed system. The system uses nano iron sulfide-modified biochar (nFeS-BC), derived from spent substrates of Lentinus edodes, as the primary adsorbent. The study determines the removal mechanisms by nFeS-BC, including ion exchange, functional group interaction, complexation and co-precipitation. Fixed bed experimental results demonstrated a maximum adsorption capacity (qe) of 2.751 mg·g−1 for Cr(VI) with an initial concentration (C0) of 20 mg·g−1, bed height (Z) of 10 cm, flow rate (Q) of 2 mL·min−1, and at pH 2. The adsorption process closely followed the Thomas and Yoon-Nelson models, confirming a high fitting accuracy (R2 = 0.997), which underscores the predictability and stability of nFeS-BC in dynamic flow conditions. Subsequent treatment in a second fixed bed, filled with cetyltrimethyl ammonium bromide-modified biochar (CTAB-BC), reduced the total Cr concentration to 0 mg·L−1. Furthermore, nFeS-BC retained 50 % of its initial adsorption capacity after five regeneration cycles. This study highlights the potential of nFeS-BC within a novel fixed-bed design for efficient and sustainable treatment of actual wastewater.

Evaluation of antioxidant, antibacterial, and anti-inflammatory activities of deodorizer distillate-derived silver nanoparticles

Silver nanoparticles (AgNPs) were synthesized using a sustainable green approach utilizing deodorizer distillates of canola (CODD) and soybean oil (SODD) as both reducing and capping agents. This synthesis approach resulted in the formation of pale-yellow colored CODD-AgNPs and SODD-AgNPs, which was confirmed by distinctive absorption peaks at 420 nm and 408 nm, respectively via Ultraviolet-Visible (UV–Vis) spectroscopy. Fourier Transform Infrared (FTIR) analysis provided insights into the functional group interactions between CODD and SODD with their AgNPs. X-ray diffraction (XRD) confirmed the face-centered cubic lattice structure of both CODD-AgNPs and SODD-AgNPs. Further characterization via Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM) revealed the sizes, shapes, and surface morphologies of CODD-AgNPs and SODD-AgNPs. Assessment of antioxidant activity using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method demonstrated superior radical scavenging efficacy by CODD-AgNPs (IC50 value 1.07±0.04 µg/mL) and SODD-AgNPs (IC50 value 1.14±0.23 µg/mL) compared to CODD and SODD. Evaluation of antibacterial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) via disc diffusion method revealed potent antibacterial activities of CODD-AgNPs and SODD-AgNPs at 100 µg/mL concentration, surpassing the antibacterial efficacy of CODD and SODD. Furthermore, CODD-AgNPs and SODD-AgNPs exhibited significant anti-inflammatory potential at 500 µg/mL concentration, with IC50 values of 187.2 ± 1.28 µg/mL and 203.9 ± 2.08 µg/mL, respectively, highlighting their potential therapeutic applications. In conclusion, this study demonstrates the effective utilization of CODD and SODD in synthesizing AgNPs with enhanced biological functionalities, making them promising candidates for various biomedical applications.

Application of Reduced Graphene Oxide-Zinc Oxide Nanocomposite in the Removal of Pb(II) and Cd(II) Contaminated Wastewater

Toxic metal wastewater is a challenge for exposed terrestrial and aquatic environments, as well as the recyclability of the water, prompting inputs for the development of promising treatment methods. Consequently, the rGO/ZnONP nanocomposite was synthesized at room temperature for four hours and was tested for the adsorption of cadmium and lead in wastewater. The optimized nanocomposite had the lowest band gap energy (2.69 eV), and functional group interactions were at 516, 1220, 1732, 3009, and 3460 cm−1. The nanocomposite showed good ZnO nanoparticle size distribution and separation on rGO surfaces. The nanocomposite’s D and G band intensities were almost the same, constituting the ZnO presence on rGO from the Raman spectrum. The adsorption equilibrium time for cadmium and lead was reached within 10 and 90 min with efficiencies of ~100%. Sips and Freundlich best fitted the cadmium and lead adsorption data (R2 ~ 1); therefore, the adsorption was a multilayer coverage for lead and a mixture of heterogenous and homogenous coverage for cadmium adsorption. Both adsorptions were best fitted by the pseudo-first-order model, suggesting the multilayer coverage dominance. The adsorbent was reused for three and seven times for cadmium and lead. The nanocomposite showed selectivity towards lead (95%) and cadmium (100%) in the interfering wastewater matrix. Conclusively, the nanocomposite may be embedded within upcoming lab-scale treatment plants, which could lead to further upscaling and it serving as an industrial wastewater treatment material.

Viscometric studies of heavy oil in the presence of compositions consisting of amphiphilic compounds and organic solvents

The chemical composition of high-viscosity heavy oil has been studied by IR spectroscopy and X-ray fluorescence spectrometry. It is found that characteristic absorption bands are available and characterize aliphatic structures and aromatic cycles, sulfur- and organophosphorus compounds, and the presence of compounds containing heteroatoms P, V, Ca, Pd, Ni, Ru, Mo, Fe, Cu and Zn in its composition is found. The method of rotational viscometry has established the Newtonian nature of the oil flow in the studied range of the velocity up to 300 s–1. At the same time, according to the densitometry results (ρ = 0.954 g/cm3 ), studied heavy oil belongs to the bituminous type characterized by a complex rheological behavior under long- and high-term deformation conditions. In order to regulate the studied oil viscosity properties, composite additives based on amphiphilic reagents of cationic and amphoteric type and organic solvents have been developed, their influence on dynamic and kinematic viscosity has been examined. It has been established that compositions with surfactants simultaneously containing a large amount of amino and phosphate groups dissolved in a non-polar aromatic solvent (toluene) or an organic mixture (catalytic reforming gasoline) have a maximum modifying effect of the colloidal structure of bituminous oil. The interaction of functional groups of amphiphilic reagents with oil heteroatoms leads to the dispersion of resinous-asphaltene substances, a decrease in the structural and mechanical strength of the system, an increase in the molecular mobility of aggregates, which results in improving the investigated oil quality and viscosity characteristics by 7.0 and 12.6 % according to the composition efficiency index.

Exploring the molecular biology of zinc-doped hydroxyapatite nanocomposites as fillers for dental materials: a self-defensive approach targeting bacterial DNA

Abstract Infections during or after the denture filling pose a serious threat to recovery later, and antibiotics are scanty for quick healing. The antibacterial potential of Zn has convinced us to fabricate its composites with hydroxyapatite (HA), which has distinct biological properties. The main aim of the study is to evaluate the antibacterial potential of Zn-doped HA and investigate its molecular interaction with bacterial strains to enhance its defensive ability against bacterial attack. This study investigates the synthesis of zinc-doped hydroxyapatite nano-powder (Zn-HA) as coating and filling materials for dental applications. The co-precipitation technique was used in this regard to obtain the purest form of nanoparticles. The as-prepared Zn-HA samples were characterized by FTIR spectroscopy to assess the interaction of functional groups between components, X-ray diffraction (XRD) to determine percentage crystallinity, SEM to explore the surface morphology of composites, and EDX to confirm the incorporation of Zn in the apatite structure. The crystalline size of Zn-HA decreases from 99 nm to 40 nm with an increase in the doping of Zncl2 from 0 to 2.5g. With increasing the concentration of Zn doping, the effectiveness of antibacterial potential was increased. Due to an increased in the concentration of doped Zn, the Zn ions effectively rupture the bacterial membrane and destroy its DNA. Meanwhile, it shows the highest antibacterial activity against Pseudomonas (20.2±0.02), Klebsiella (25.8±0.05), Bacillus (18.3±0.09), S. aureus (24±0.03), and E. coli (19.3±0.09) with Zn/HA5.It showed that by increasing the concentration of Zinc ions in hydroxyapatite, the antibacterial potential increased. This increased concentration of zinc ions in HA enhances its-defensive ability against the attack of various bacterial strains, this makes it a potential material and enhances its efficacy in dental applications like coating, filling material, or dental restoratives, in inhibiting the growth of bacterial colonies and biofilm formation in the oral cavity. In this way, Zn/HA as an efficient dental composite as a restorative material with enhanced antibacterial potential may help to mitigate the risk of dental infections, promote dental as well as oral health, and overall improve the life of dentine.

Antibacterial, Mechanical, and Thermal Properties of Ag, ZnO, TiO2 Reinforced PVA Nanocomposite Fibers

AbstractThis study investigated the effects of concentration and electrospinning parameters on the production of poly (vinyl alcohol) (PVA) nanofibers and examined the impact of reinforcing additives like nano‐sized silver (Ag), titanium oxide (TiO2), and zinc oxide (ZnO) on these nanofibers. The PVA concentration was varied between 3 % and 10 % wt./v, while the flow rate was adjusted to 0.5, 1, and 5 ml/h. The optimal conditions for producing PVA nanofibers are a concentration of 10 % wt./v at a flow rate of 0.5 ml/h and an applied voltage of 9 kV, resulting in nanofibers with an average diameter of 502±0.10 nm. PVA nanofibers reinforced with nano‐sized 3 % wt. Ag, TiO2, and ZnO and electrospun at optimum conditions. The morphological properties were determined using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM), and the average fiber diameter was measured with the Image J program. The presence of nanoparticles within the nanofibers was confirmed through Energy Dispersive Spectrometry (EDS) and X‐ray diffraction (XRD). Chemical interactions of functional groups between PVA and ZnO, TiO2, and Ag NPs were analyzed with Fourier Transform Infrared Spectroscopy (FTIR), and thermal behaviors were studied with Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Among the water absorption, Ag‐reinforced PVA nanofibers showed maximum absorbance. Mechanical properties, evaluated through tensile testing, showed the elastic modulus of the nanocomposite fibers to be 38.07±12.01 MPa for PVA/Ag, 88.98±27.5 MPa for PVA/TiO2, and 30.56±9.77 MPa for PVA/ZnO. The antimicrobial activity of the nanoparticle‐reinforced PVA nanofibers was tested using the agar disc diffusion method. The results showed that both Ag and TiO2 reinforced PVA nanocomposite fibers exhibited significant antimicrobial activity (gram–(Escherichia coli) and gram+(Staphylococcus aureus)), with inhibition zones of 8.48±0.08 cm against E. coli and 9.98±0.47 cm against S. aureus for Ag, and 4.32±0.02 cm against E. coli and 3.56±0.05 cm against S. aureus for TiO2.

Chemical stitching of a reduced and fluorine decorated graphene oxide quilt

This work demonstrated the possibility of obtaining continuous thin transparent films of reduced graphene oxide of large size. The process of chemical interaction of individual graphene oxide microsheets is implemented in a planar version on a silicon substrate with an oxide layer during preheating and subsequent reduction under hydrothermal conditions. Based on the results of thermal analysis, in situ X-ray diffraction, and results of XPS, a model of the chemical interaction of functional groups of graphene oxide during its primary thermal and subsequent hydrothermal treatment is proposed. The thin films obtained in this work were transferred to a measuring structure and their conductive properties were measured in planar and vertical geometries.

Synthesis of Modified Nano-Hydrotalcite Clay by Micellar Method and Its Application as Gel-like Crude Oil Flow Improver.

The network formed by wax precipitation at low temperature and colloid asphaltene at high temperature leads to poor fluidity of heavy oil, and the gelling characteristics of crude oil lead to pipeline blockage, which affects the exploitation, transportation and refining of crude oil. This work prepares a series of cationic surfactant-modified nano hydrotalcite (CSNH) to weaken the network structure and enhance the fluidity of the crude oil by the interaction of organic and inorganic functional groups on the CSNH surface and the components of the crude oil. The results show that CSNHs can all reduce the viscosity of crude oil from different oilfields, among which BTNH can reduce the viscosity of Yanglou (YL) crude oil by 98.8% (31 °C) and depress the pour point by 16.0 °C at most. In the investigation of the universality of crude oil, the modified hydrotalcite was applied to the mixed crude oil (CQH) of Changqing Oilfield, the crude oil (J76) of Jidong Oilfield, the high pour point oil (GN) of Huabei Oilfield, and the crude oil (HQ) of Tuha Oilfield. The viscosity reduction rates were 53.2%, 86.2%, 42.7%, and 63.8%, respectively. The characterization of this nano material confirms the modification of quaternary ammonium cationic surfactant on the surface, resulting in a smaller particle size, and the nano particles are stable under conventional conditions. The mechanism of viscosity and pour point reduction in crude oil by BTNH was discussed by DSC and optical microscopy analysis. The OH- and long-chain alkyl groups on the BTNH surface may interact with the resins, asphaltene and wax through hydrogen bonding and co-crystal, weakening or dispersing their aggregates, thereby improving the fluidity of crude oil. Finally, a cost evaluation was conducted on BTNH, providing useful support for subsequent promotion and application.

Improving the removal rate of bisphenol A and Cu2+ from water using P/N coexisting β-cyclodextrin-based adsorbents by enhancing adsorbents-pollutants interactions

Bisphenol A (BPA), a prominent endocrine-disrupting compound, has garnered considerable attention due to its urgent need for rapid removal from water. Herein, we first used a novel reactive phosphine oxide containing tertiary amines as crosslinker to prepare water-insoluble crosslinked β-cyclodextrin (β-CD) adsorbent via radical-mediated thiol–ene polymerization. Owing to the synergistic hydrogen-bond (H-bond) interactions of functional groups (tertiary amine and PO groups) toward BPA, the resulted adsorbents showed fast adsorption kinetics to BPA with an adsorption equilibrium time of 5 min. After six adsorption–desorption cycles, the removal efficiency of BPA was 92.5 %, indicating its excellent reusability. Due to the presence of the CS bonds, the β-CD -derived bio-adsorbents offered binding sites for Cu2+ ions, resulting in a maximum adsorption capacity of 113.89 mg g−1.

Plant functional group interactions intensify with warming in alpine grasslands

Plant–plant interactions regulate plant community structure and function. Shifts in these interactions due to global climate change, mediated through disproportional increases of certain species or functional groups, may strongly affect plant community properties. Still, we lack knowledge of community‐level effects of climate‐driven changes in biotic interactions. We examined plant community interactions by experimentally removing a dominant functional group, graminoids, in semi‐natural grasslands in Southern Norway. To test whether the effect of graminoid removal varied with climate, the experiment was replicated across broad‐scale temperature and precipitation gradients. To quantify community‐level interactions across sites, we tested for changes in the remaining vascular community (i.e. forbs) cover, richness, evenness, and functional traits reflecting leaf‐economic investment and plant size over five years. The effect of graminoid removal on forb community structure and functioning varied over time, and along the climate gradients. Forb cover increased in response to graminoid removal, especially at warmer sites. Species richness increased following removal irrespective of climate, whilst evenness increased under warmer and wetter conditions irrespective of removal. No climate or removal effect was found for species turnover. Functional trait responses varied along the precipitation gradient – compared to controls, forb mean SLA decreased in drier conditions after graminoid removal. Leaf thickness increased under cooler and drier conditions irrespective of removal. These community structure alterations demonstrate stronger competitive interactions between forbs and graminoids under warmer conditions, whilst functional trait responses indicate a facilitative effect of graminoids under drier conditions. This indicates that both competition and facilitation regulate plant communities, suggesting complexity when scaling from populations to communities. Finally, both temperature and precipitation determine the direction and intensity of biotic interactions, with ecosystem‐wide implications for forb persistence and ecosystem functioning under future climates. Further work is needed to generalise the role of changing interactions in mediating community responses to climate change.

Novel ferrocene-based graphene oxide/Polypyrrole nanocomposites: Electro-capacitive properties study

In this research, we fabricated two novel ferrocene-modified graphene oxide (GO) nano-hybrids as electrode material for supercapacitors. Particularly, the physicochemical interaction of GO surface functional groups and as-synthesized ferrocenyl derivative, along with physical addition of polypyrrole (PPy) resulted in the preparation of high-performance battery-type capacitive materials. The GO-FBF1/PPy, and GO-FBF2/PPy, as final nanocomposites exhibited 229.43 and 269.57 mAhg−1 charge storage capacity, and capacity retention of 91 % and 93 % over 5000 CV cycles, respectively. Also, a symmetric supercapacitor (SSC) with GO-FBF2/PPy as both the anode and cathode exhibits exceptional cycling performance, with 95 % of its capacity remaining after 3000 cycles, and can be operated in a broad electrochemical window up to 1.6 V. Furthermore, our SSC device shows remarkable power and energy densities of 7859 W kg−1 and 123 Wh kg−1, respectively. For high-performance SCs, this research offers a way to improve the electrochemical characteristics of redox-active battery-type electrode materials.

Predicting Odor Sensory Attributes of Unidentified Chemicals in Water Using Fragmentation Mass Spectra with Machine Learning Models.

Knowing odor sensory attributes of odorants lies at the core of odor tracking when addressing waterborne odor issues. However, experimental determination covering tens of thousands of odorants in authentic water is not pragmatic due to the complexity of odorant identification and odor evaluation. In this study, we propose the first machine learning (ML) model to predict odor perception/threshold aiming at odorants in water, which can use either molecular structure or MS2 spectra as input features. We demonstrate that model performance using MS2 spectra is nearly as good as that using unequivocal structures, both with outstanding accuracy. We particularly show the model's robustness in predicting odor sensory attributes of unidentified chemicals by using the experimentally obtained MS2 spectra from nontarget analysis on authentic water samples. Interpreting the developed models, we identify the intricate interaction of functional groups as the predominant influence factor on odor sensory attributes. We also highlight the important roles of carbon chain length, molecular weight, etc., in the inherent olfactory mechanisms. These findings streamline the odor sensory attribute prediction and are crucial advancements toward credible tracking and efficient control of off-odors in water.

Evaluation of a chitosan-based hydrogel containing graphene oxide and Scrophularia striata extract as an antimicrobial wound dressing

In the realm of wound care, hydrogels have emerged as a promising treatment option owing to their properties such as high water absorption, biocompatibility, and soft structure. This research focuses on the development of a chitosan/guar gum/ polycaprolactone (CS/GG/PCL) hydrogel treated with graphene oxide (GO) and Scrophularia striata (SS) extract for burn wound healing applications. The synergistic combination of these components aims to enhance the hydrogel's efficacy in delivering herbal medicines for wound treatment. Scrophularia striata, known for its diverse biological activities, was incorporated into the hydrogel due to its antimicrobial, antitumor, biliary stimulation, hemodynamic, analgesic, anti-inflammatory, and hepatoprotective effects. The network structure and functional group interactions of CS/GG/PCL hydrogel were investigated by FE-SEM and FTIR. Subsequent evaluations revealed that the hydrogel exhibited over 135 % swelling in water, with the SS extract enhancing its hydrophilicity. Additionally, the release of SS extract from the composite hydrogel reached 98 % in phosphate-buffered saline (PBS) solution after 180 min at pH 7.4. Notably, SS extract demonstrated excellent antibacterial activity against both Staphylococcus aureus and Escherichia coli bacteria. Furthermore, the hydrogel exhibited no cytotoxic effects on human foreskin fibroblast (HFF) cells, with the cell proliferation actually improving. Therefore, the CS/GG/PCL composite hydrogel enriched with GO and SS extract presents a promising avenue for delivering herbal medicines, positioning it as a potential candidate for advanced wound healing applications.

Assembly of core-shell Fe3O4 @CD-MOFs derived hollow magnetic microcubes for efficient extraction of hazardous substances: Plausible mechanisms for selective adsorption

Hazardous heavy metals and organic substances removal is of great significance for ensuring the safety of aquatic-ecosystem, yet the highly effective and selective extraction always remains challenging. To address this problem, magnetic hollow microcubes were fabricated through thermal carbonization of Fe3O4-COOH@ γ-CD-MOFs, and core-shell structured precursors were in-situ greenly constructed on a large scale via microwave-assisted self-assembly strategy. As noted, the development of secondary crystallization was utilized to achieve uniform dispersion of cores within MOFs frameworks and thus improved magnetic and adsorption ability of composites. Acquired magnetic Fe3O4 @HC not only can harvest excellent extraction of heavy metals (Cd, Pb, and Cu of 129.87, 151.05, and 106.98 mg·g−1) but also exhibit highly selective adsorption ability for cationic organics (separation efficiency higher than 95.0 %). Impressively, Fe3O4 @HC achieved outstanding adsorption (60–80 %) of Cd in realistic mussel cooking broth with no obvious loss in amino acid. Characterizations better offer mechanistic insight into the enhanced selectivity of positively charged pollutants can be attributed to synergistic effect of ions exchange and electrostatic interaction of abundant oxygen-containing functional groups. Our study provides a feasible route by rationally developing core-shell structured composites to promote the practical applications of sustainable water treatment and value-added utilization of processing by-products.

Unraveling the Phosphorus Adsorption Mechanisms in Three-dimensional Reduced Graphene Oxide Materials.

To prevent eutrophication, controlling the phosphate concentration levels is one of the most important issues in surface water management. One of the most utilized methods is phosphate adsorption. However, its application faces a bottleneck due to the unclear understanding of adsorption and interaction mechanisms. The present work unlocks the phosphorus adsorption mechanisms in three-dimensional reduced graphene oxide with different reduction levels and pore sizes to remove phosphate from water using experiments and multiscale simulations. Experiments were performed to evaluate the influence of pH, ionic strength, and temperature on the adsorption. Molecular Dynamics and Ab Initio simulations evaluated the influence of the pore size and oxidation degrees of the materials. We show that the adsorption capacity of the materials increases with increasing pH and ionic strength and decreasing temperature. It is observed that the more oxidized the material and the less compact the structure, the better the adsorption. These results are theoretically explained in terms of the interaction of functional groups and the clustering of phosphate ions, which results in better adsorption in materials with larger pores. The underlying mechanisms for the 3D-reduced graphene oxide performance were confirmed by spectroscopy analysis. All the results show that 3D-reduced graphene oxide can sorb phosphate in different complex water remediation systems with characteristics that can be modulated by changing the material synthesis method.

Driving Role of Zinc Oxide Nanoparticles with Different Sizes and Hydrophobicity in Metabolic Response and Eco-Corona Formation in Sprouts (Vigna radiata).

Zinc oxide nanoparticles (ZnO NPs) cause biotoxicity and pose a potential ecological threat; however, their effects on plant metabolism and eco-corona evolution between NPs and organisms remain unclear. This study clarified the molecular mechanisms underlying physiological and metabolic responses induced by three different ZnO NPs with different sizes and hydrophobicity in sprouts (Vigna radiata) and explored the critical regulation of eco-corona formation in root-nano systems. Results indicated that smaller-sized ZnO inhibited root elongation by up to 37.14% and triggered oxidative burst and apoptosis. Metabolomics confirmed that physiological maintenance after n-ZnO exposure was mainly attributed to the effective stabilization of nitrogen fixation and defense systems by biotransformation of the flavonoid pathway. Larger-sized or hydrophobic group-modified ZnO exhibited low toxicity in sprouts, with 0.89-fold upregulation of citrate in central carbon metabolism. This contributed to providing energy for resistance to NP stress through amino acid and carbon/nitrogen metabolism, accompanied by changes in membrane properties. Notably, smaller-sized and hydrophobic NPs intensely stimulated the release of root metabolites, forming corona complexes with exudates. The hydrogen-bonded wrapping mechanism in protein secondary structure and hydrophobic interactions of heterogeneous functional groups drove eco-corona formation, along with the corona evolution intensity of n-ZnO > s-ZnO > b-ZnO based on higher (α-helix + 3-turn helix)/β-sheet ratios. This study provides crucial insight into metabolic and eco-corona evolution in bionano fates.

Alginate functionalized chitosan nanoparticles using multilayer co-axial electro-spraying for ovalbumin controlled release via oral delivery

The current oral vaccine delivery presents numerous challenges due to physiological barriers in the gastrointestinal tract including antigen degradation by enzymes and gastric pH conditions. Contributing to overcome these problems, this work developed non-cross-linked chitosan (CHI) nanoparticles, with/without functionalization with alginate (ALG), using multilayer co-axial electro-spraying method, to orally deliver ovalbumin (OVA), a model antigen. The prepared OVA@CHI and OVA@CHI@ALG nanoparticles possessed spherical shape, uniform size and non-agglomeration, high OVA encapsulation efficiency of above 90 %, and core-shell structure with mean diameters of 276.9 ± 70.7 nm (for OVA@CHI) and 304.3 ± 63.9 nm (for OVA@CHI@ALG), determined via SEM images. The particle hydrodynamic diameters, analyzed by the DLS method, were 313.0 ± 72.4 nm for OVA@CHI and 367.6 ± 83.2 nm for OVA@CHI@ALG, in agreement with the SEM results. Additionally, the material functional group interactions and the polyelectrolyte complex formations were confirmed by FTIR spectra and TGA/DSC thermo-grams, indicating the successful formulation. Subsequently, the OVA@CHI@ALG nanoparticles revealed good stability in acidic environment under the presence of digestive enzymes. The OVA release profiles of OVA@CHI@ALG nanoparticles exhibited limited release in simulated gastric fluid (pH 1.2), followed by sustained release in simulated intestinal fluid (pH 6.8) and simulated colonic fluid (pH 7.4) over a 48-h test period. Interestingly, the primary structure of OVA, analyzed by SDS-PAGE analysis, was maintained during the preparation process and after the release test, while the OVA secondary structure, examined by circular dichroism measurement, demonstrated a decrease of α-helix and an increase of β-sheet contents. Finally, the in vitro mucin-binding study indicated a significant adhesive efficiency of 69.21 ± 4.24 % for OVA@CHI and 75.07 ± 2.58 % for OVA@CHI@ALG at pH 7.4. Conclusively, the OVA@CHI@ALG nanoparticles fabricated by tri-axial electro-spraying method could be a promising oral vaccine delivery system for sustained release of OVA.