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The primary objective of this investigation was to develop a new nanocatalyst that could produce materials with a lower sulfur content, thereby reducing its environmental harm. To achieve this, the researchers used the sol‐gel method to synthesize a heterogeneous nanocatalyst by attaching sandwich‐type polyoxotungstate [(CuW9O34)2Cu4(H2O)2−10] (denoted as Cu6W18O70) clusters on the surface of copper ferrite nanoparticles (CuFe2O4 NPs). To characterize the nanocatalyst, several analysis techniques were employed, including Fourier transform infrared spectroscopy, ultraviolet‐visible, powder X‐ray diffraction, and scanning electron microscope. The oxidative desulfurization of hazardous sulfur‐containing real and model fuel oils was effectively catalyzed by the Cu6W18O70⊂CuFe2O4 nanocatalyst. According to the experimental findings, the best efficiencies in oxidation reaction were achieved in 1 h contracting time at 35°C, which was as high as 95%. The Cu6W18O70⊂CuFe2O4 nanocatalyst exhibited impressive removal rates (%) on dibenzothiophene (C12H8S), benzothiophene (C8H6S), and thiophene (C4H4S) of model fuels, with figures reaching 97%, 96% and, 96% respectively. Furthermore, multiple recycling of the uniform nanocatalyst can be achieved effortlessly through filtration, without experiencing any notable decline in activity. Therefore, the authors suggest that this study will pave the way for the widely used mentioned nanocatalyst in the practical and workable organization of petroleum fractions. [ABSTRACT FROM AUTHOR]

To investigate the reinforcing effect of nanoflower‐like hydroxyapatite (NFHA) in resin‐based dental composites, we synthesized a novel NFHA using microwave irradiation (MW), hydrothermal treatment (HT), and sonochemical synthesis (SS). Silanized NFHA was then used as the reinforcing filler in dental resin composites. We characterized the structure and morphology of various HA nanostructures using x‐ray diffraction, scanning electron microscope, and TEM. The mechanical performance of dental resin composites reinforced with silanized NFHA was measured using a universal testing machine. Spherical HA, synthesized through chemical precipitation (CP), served as the control group. One‐way analysis of variance was employed for the statistical analysis of the acquired data. The results demonstrate that the nanoflower morphology significantly was improved mechanical and physical properties. After conducting trials, the NFHA synthesized using MW and HT showed a substantial enhancement in mechanical and physical properties compared to the other structures. Therefore, it can be concluded that NFHA can serve as a novel reinforcing HA filler, providing regenerative properties to resin composites with sufficient mechanical strength. [ABSTRACT FROM AUTHOR]

This research aims at investigating the idea of anti‐bacterial self‐healing coatings based on polyurea formaldehyde microcapsules (MCs), with the repair agent being ZnO‐containing linseed oil. ZnO nanoparticles were added to the repair agent with the idea of developing an antibacterial coating. The idea was to entrap some ZnO nanoparticles inside microcapsules, aiming for some local release of ZnO nanoparticles where the coating is damaged. The corrosion resistances of the coatings were studied using the Tafel polarization test. The structure of the coating samples was evaluated using a scanning electron microscope. To check the antibacterial properties of ZnO‐containing self‐healing samples, Escherichia coli and Staphylococcus aureus bacteria were used. Results showed that ZnO nanoparticles were distributed not only inside microcapsules but also over the walls, inferring that overall protection can also be attained in addition to local anti‐bacterial performance. Results showed that the proposed multi‐functional coating has promising antibacterial and self‐healing responses. [ABSTRACT FROM AUTHOR]

The research aimed to prepare eco-friendly bio-nanocomposite films utilizing gelatin/ starch (GS), nano-ZnO, and Darbha grass extract via the solution casting method. Then, it was examined the mechanical and physical properties of different durations of sunlight exposure on the prepared films. The results indicated that up to 12 h of sunlight exposure led to increased film thickness, mechanical strength, and apparent density. Tensile strength increased from 4.8 to 34.8 MPa, and the average crystalline size of the nanoparticles was found to be 54.35 nm using scanning electron microscope. Compared with GS films, these bio-nanocomposite films exhibited lower moisture content, oil permeability, and enhanced water barrier properties. Moreover, they displayed significant UV absorption and profound antimicrobial activity against both gram-positive and gram-negative food borne pathogenic bacteria. The nano-ZnO/Darbha grass extract-based bio-nanocomposite films exhibited showed improved characteristics and could be applied in the field of food packaging application. [ABSTRACT FROM AUTHOR]

The areas of environmental cleanup and bacteria inactivation are particularly interesting in polymer-based nanomaterials because of their unique physicochemical properties. Conjugated polymer nanoparticles (CP NPs) have potential uses in the biological and environmental, but little is known about them. This study aimed to examine the efficacy of CP nanoparticles in the photocatalytic inactivation of S. aureus and E. coli under visible irradiation (λ ≤ 420 nm), with minor enhancements observed. The simple and one-step chemical oxidation technique was used to prepare CP nanoparticles. X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), Energy-dispersive X-ray (EDS), and Transmission electron microscopy (TEM) analyses were utilized to characterize the physicochemical properties of CP nanoparticles for comprehensive structural analysis. The synthesized CP nanoparticles exhibited outstanding photocatalytic disinfection capabilities, achieving a degradation of 98.6%. This research not only provides insights into the physical characteristics of CP nanoparticles but also illustrates their antibacterial efficacy against two different bacterial pathogens, namely S. aureus and E. coli. Therefore, this research highlights an eco-friendly and inexpensive preparation of conjugated polymer nanoparticles for a wide range of applications. [ABSTRACT FROM AUTHOR]

This study presents the effect of chitosan on the properties of zinc ferrite nanoparticles suitable for potential biomedical applications. The co‐precipitation method is employed to fabricate these bio‐composites that exhibit excellent microstructural properties. The X‐ray diffractometer (XRD) analysis confirms the presence of a cubic spinel structure in the zinc ferrite‐chitosan bio‐composites, indicative of their crystalline nature. Scanning electron microscope (SEM) imaging revealed spherical particles with a size distribution below 100 nm, demonstrating the successful synthesis of homogenous nanosized particles. Fourier transform infrared spectroscopy (FTIR) spectroscopy analysis identifies the active functional groups within the bio‐composites, providing valuable insights into the molecular structure and interactions present in the synthesized materials. The presence of chitosan is confirmed, highlighting its role in modifying the chemical composition and enhancing the biocompatibility of the samples. UV–vis absorption spectra analysis reveals that the samples exhibits absorbance within the visible range. Vibrating sample magnetometer (VSM) analysis demonstrates the superparamagnetic behavior of the samples. Remarkably, these formulated samples exhibit superparamagnetism with zero coercivity and a magnetization of ≈0.0125 emu g−1 at 5 kOe when doped with chitosan. These properties are crucial for potential biomedical applications making it a promising candidate for various biomedical applications. [ABSTRACT FROM AUTHOR]

Boehmite is one of the stable phases of alumina that is easily available, and it also has a variety of applications. Therefore in this work, for preparation of AlOOH, Sodium hydroxide (NaOH) solutions was added to aluminum nitrate nonahydrate (Al(NO3)3.9H2O) solution. Then, the surface of AlOOH was modified with (3‐aminopropyl)triethoxysilane (APTES), due to high condensation of hydroxyl groups on its surface. Then, di(pyridin‐2‐yl)methanone (di(PM)) was immobilized on the surface of modified AlOOH toward synthesis of immobilized Schiff‐base on AlOOH (di(PM)@AlOOH) as a heterogeneous Schiff‐base ligand. Finally, a palladium complex was immobilized on its surface (Pd‐di(PM)@AlOOH) as a reusable, practical, and novel nanocatalyst. Pd‐di(PM)@AlOOH was characterized by thermogravimetric analysis (TGA) analysis, Fourier‐transform infrared spectroscopy (FT‐IR), transmission electron microscopy (TEM), scanning electron microscope (SEM) imaging, energy‐dispersive X‐ray spectroscopy (EDS) analysis, wavelength‐dispersive X‐ray spectroscopy (WDX) analysis, and inductively coupled plasma (ICP) analysis. After the characterization of Pd‐di(PM)@AlOOH, its performance was used as a highly practical, stable, retrievable, and hybrid organic–inorganic catalyst in the C‐C coupling of the Suzuki reaction. The hot filtration study of Pd‐di(PM)@AlOOH revealed that it acts heterogeneously in the Suzuki reaction. We found that this catalyst can be recycled for five runs without palladium leaching, as studied by hot filtration test and ICP analysis. [ABSTRACT FROM AUTHOR]

Summary: The present study evaluated the production of galactooligosaccharides (GOSs) from lactose in both batch and continuous modes using nano‐immobilised β‐galactosidase. Mesoporous silicon dioxide nanoparticles were used to immobilise β‐galactosidase to enhance the stability and production of GOSs. The change in enzyme‐characteristics was assessed using Fourier‐transform infrared and scanning electron microscope analysis. The nano‐immobilisation increased the enzyme's substrate affinity, but decreased its hydrolytic activity. A significant increase (P < 0.05) in stability was observed across a wide range of temperature (30 °C–70 °C) and pH (5.0–8.0). Both forms of enzymes (free and nano‐immobilised enzymes) followed the zero‐order reaction in all temperatures, while the nano‐immobilised enzyme had the highest activation energy. The free and nano‐immobilised enzymes retained 64.65% and 77.82% of their initial activity after 90 days of storage, respectively. In a batch mode, the nano‐immobilised enzyme produced 2.35 times more GOSs than the free enzyme. The GOSs production remained consistent while the enzyme activity decreased by 12.7% after 5 cycles of operation. The continuous mode of production in a packed bed reactor achieved a GOSs yield of 16.92%. Overall, the nano‐immobilised enzyme showed better GOSs production under batch and continuous mode of operation. [ABSTRACT FROM AUTHOR]

The emergence of antibiotic‐resistant bacterial infections is a principal threat to global health. Functionalization of nanomaterial with antibiotics is known as a useful method for increasing the effectiveness of existing antibiotics. In this study, vancomycin‐functionalized ZnFe2O4 nanocomposite (ZnFe2O4@Cell@APTES@Van) was synthesized, and its functional groups and particle size were characterized using Fourier‐transform infrared spectroscopy, thermogravimetric analysis, dynamic light scattering, scanning electron microscope, and transmission electron microscopy. The antibacteria activity of the synthesized nanocomposite was evaluated using minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli, Staphylococcus aureus, and methicillin‐resistant Staphylococcus aureus (MRSA). Cytotoxicity assay was done by 2,3‐bis‐(2‐methoxy‐4‐nitro‐5‐sulfophenyl)‐2H‐tetrazolium‐5‐carboxanilide method. Characterization analyses of synthesized nanocomposite confirmed the binding of vancomysin on the surface of ZnFe2O4@Cell@APTES. Nanocomposite exhibited an aggregated semi‐spherical structure with hydrodynamic radii of ∼382 nm. In vitro antibacterial activity test showed that vancomycin and vancomycin functionalized ZnFe2O4 have no antibacterial effect against E. coli. S. aureus was sensitive to vancomycin and ZnFe2O4@Cell@APTES@Van NPs and ZnFe2O4 NPs did not improve vancomycin antibacterial activity against these bacteria. MRSA is resistant to vancomycin while ZnFe2O4@Cell@APTES@Van NPs was efficient in inhibiting MRSA growth. In summary, this study showed that attachment of vancomycin to ZnFe2O4 NPs was increased its antibacterial activity against MRSA. [ABSTRACT FROM AUTHOR]

Plant‐based nanoparticles (NPs) have found great interest among various scientist in the present era and used in various sector including medicine, agriculture, and food industry. The various chemical constituents of plants aid in the bioreduction of metal ions to a nanoscale. Among the various NPs synthesized, zinc oxide (ZnO) NPs hold a premier position. ZnO NPs have use in textile, cosmetic, diagnostics, optoelectronics, photocatalysis, diodes, and many other areas. NPs synthesized through green synthesis have a potentially greater role in treating clinical pathogens. Present investigations show a simple eco‐friendly method for the synthesis of ZnO NPs from the husk of sunflower seeds. Sunflower is an economically important crop, for the formation of edible oil. The husk is considered to be a waste, product in oil industry, however, the biomolecules present in sunflower husk can be used to produce ZnO NPs. Present investigations reveal formation of ZnO NPs and investigations of their structure through scanning electron microscope (SEM), X‐ray diffraction (XRD), and Fourier transform infrared (FTIR) spectroscopy. Their optical properties have been studied by ultraviolet–visible spectrophotometer (UV–Vis) and fluorophotometer. ZnO NPs have also been investigated for their potential phytoremedial properties. [ABSTRACT FROM AUTHOR]