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Using an in situ sol-gel technique, new nanoarchitectonics of propolis loaded zinc oxide nanoarchitectonics (PP/ZnO-NPs) were developed in order to improve the in vivo outcomes of collagen-chitosan gel in wounded rats. The obtained nanoarchitectonics were fully characterized. The XRD results indicate the presence of a Zincite phase for ZnO-NPs and Zincite accompanied by a minor amount of zinc hydroxide for PP/ZnO-NPs samples. While the TEM findings illustrate the transfer of the ZnO-NPs from agglomerated spheres with an average particle size of 230 ± 29 nm to needle-like NPs of 323 ± 173 nm length (PP1/ZnO-NPs) and to a sheet-like NPs of 500 ± 173 nm diameter (PP2/ZnO-NPs). In addition, the incorporation of PP results in an increase in the surface negativity of ZnO-NPs to -31.4 ± 6.4 mV for PP2/ZnO-NPs. The antimicrobial activities of the nanocomposite gel loaded with 10%PP1/ZnO-NPs (G6) revealed the highest inhibition zone against E. coli (26 ± 2.31 mm). Remarkably, the in vivo outcomes showed that the nanocomposite gel (G6) has exceptional collagen deposition, quick wound closure rates, and re-epithelization. The outcomes demonstrate the nanocomposite gel encouraging biological properties for the treatment of damaged and infected wounds., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Paper coating plays an important role in the paper properties, printability and application. The nanocoating is a multifunction layer that provides the paper with unique features. In this work, nanocoating formulas were prepared using a green method and component. The nanocoating formulas were based on biopolymers nanostarch NSt and nanochitosan NCh (NCS) decorated with Egyptian kaolinite Ka doped with zinc nanoparticles NCS@xka/ZnONPs (x represents different ratios) support for multifunctional uses. The nanocoating formulas were characterized using a physiochemical analysis as well as a topographical study. FTIR, XRD, SEM and TEM techniques were used. Additionally, the antimicrobial activity of the tested samples was assessed against six microorganisms including Gram-negative and Gram-positive bacteria. The prepared nanocoating formulas affirmed excellent antimicrobial activity as a broad-spectrum antimicrobial active agent with excellent activity against all representative microbial communities. The nanocoating with the highest ratio of Ka/ZnONPs (NCS@40 ka/ZnONPs) showed excellent antimicrobial activity with an inhibition percentage of more than 70% versus all microorganisms presented. The paper was coated with the prepared suspensions and characterized concerning optical, mechanical and physical properties. When Ka/ZnONPs were loaded into NCS in a variety of ratios, the characteristics of coated paper were enhanced compared to blank paper. The sample NCS@40 ka/ZnONPs increased tensile strength by 11%, reduced light scattering by 12%, and improved brightness and whiteness by 1%. Paper coated with NCh suspension had 35.32% less roughness and 188.6% less porosity. When coated with the sample NCS@10 ka/ZnONPs, the coated paper's porosity was reduced by 94% and its roughness was reduced by 10.85%. The greatest reduction in water absorptivity was attained by coating with the same sample, with a reduction percentage of 132%., (© 2023. The Author(s).)

The morphology of metal oxide is a crucial factor for improving of catalysis properties. As a renewable and environmentally friendly biomass material, cellulose has been widely used to induce the morphology of semiconductors. The contributions of cellulose hydroxyl groups and spatial hindrance in tailoring Al doped ZnO (AZO) morphologies were investigated. The morphology of AZO could be gradually induced from flake-like to flower-like with the increase of cellulose hydroxyl content per unit volume. At the same time, the changes in spatial hindrance had no apparent effect on the morphology of AZO. So the cellulose hydroxyl groups that act to induce the in situ growth of AZO nanoparticles on cellulose substrates. The results further confirmed the strong interaction between cellulose hydroxyl groups and Zn 2+ . In addition, the photocatalytic activities of Al-doped ZnO/cellulose nanocomposites (AZOC) with different morphologies were evaluated by the degradation of bisphenol A (BPA). The high hydroxyl contents of cellulose substrates contributed to the growth of flower-like AZO with high light utilization and photocatalytic activity. This work proposed cleaner strategies to modify semiconductor morphologies for photocatalysis by regulating the content of cellulose hydroxyl contents., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Bacterial infection has become one of the major threats to human health all over the world, and the development and application of antibacterial materials has drawn great attention. Based on the Schiff-base structure, ZnONPs@ACFs are obtained by loading zinc oxide nanoparticles (ZnONPs) on amino cellulose fibers (ACFs) in-situ through the coordination of amino groups with metal ions. The results of FT-IR, XRD and UV-vis demonstrate that ZnONPs are successfully loaded and uniformly dispersed on ACF surface, and the ACFs maintain intact morphology observed by SEM. Furthermore, the zero-span tensile strength of ZnONPs@ACFs is 66.48 N/cm (ROL: 24.98 N/cm/s) under the optimum conditions, which indicates that ZnONPs@ACFs have a certain strength and can be used to make antibacterial sheet materials via paper-making wet-forming process. Accordingly, the ZnONPs@ACF composites show inhibition zones of 4.95 mm and 1.10 mm against E. coli and S. aureus, respectively. The new cellulose-based antibacterial materials demonstrate potential applications in the field of food packaging and biological medicine etc., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Recently, cellulose nanocrystals (CNs) have attracted wide attention owing to their superior properties compared to their bulk materials. For example, they represent an outstanding model for fabricating green metallic/metal oxide nanoparticles (NPs). In this study, two CNs (carboxylated CNs and sulfated CNs) extracted from agro-wastes of palm sheath fibers were used as templates for the facile and green synthesis of ZnO NPs by employing the sono-co-precipitation method. The obtained nanomaterials were characterized using TEM, EDX, UV-visible, DLS, FT-IR, and XRD analysis. As a result, the size and concentration of synthesized ZnO NPs were inversely proportional to one another and were affected by the CNs utilized and the reaction temperature used. Contagious diseases incited by multifarious toxigenic bacteria present severe threats to human health. The fabricated bio-nanocomposites were evaluated in terms of their antimicrobial efficacy by agar well diffusion method and broth microdilution assay, showing that CN-ZnO bio-nanocomposites were effective against the tested Gram-negative (Escherichia coli and Salmonella) and Gram-positive (Listeria monocytogenes and Staphylococcus aureus) bacteria. The influence of the subinhibitory concentrations of these suspensions on the expression of the most critical virulence toxin genes of the tested strains was effective. Significant downregulation levels were observed through toxigenic operons to both fabricated CN-ZnO bio-nanocomposites with a fold change ranging from 0.004 to 0.510, revealing a decline in the capacity and virulence of microorganisms to pose infections. Therefore, these newly fabricated CNS-ZnO bio-nanocomposites could be employed rationally in food systems as a novel preservative to inhibit microbial growth and repress the synthesis of exotoxins., (© 2022. The Author(s).)

Spruce kraft lignin (SKL) has received considerable attention in recent years for its application in the field of polymer materials. However, its structural complexity and polydispersity pose significant challenges for commercial applications. In this study, molecular structure models of acetone soluble kraft lignin (ASKL) and acetone insoluble kraft lignin (AIKL) were proposed based on quantitative calculations of the connection mode of functional groups and structural units. The lignin was modified by quaternization and synthesized in situ as lignin/ZnO composites. Based on the detailed characterization of the micromorphology and structure of the composites, waterborne polyurethane (WPU) films were optimally prepared using 0.6 wt% of the composites. The results showed that the composite films prepared from ASKL have the best UV-blocking performance and mechanical properties. The highest UVA and UVB blocking rates were 98% and 100%, respectively, and the highest tensile strength and elongation at break were 31.2 MPa and 732%, respectively. The differences in the structure and functional groups of the different types of SKL were accurately identified. ASKL is advantageous for the development of UV-blocking films because of its low molecular weight and the presence of abundant phenolic hydroxyl groups, which facilitate the formation of hydrogen bonds, improve the compatibility, and ensure uniform dispersibility. The results of this study are of practical importance in the field of nano-functional materials for the high-value application of industrial lignin., (Copyright © 2022 Elsevier B.V. All rights reserved.)

In this present work, a new design for antimicrobial wound bandages is presented. The wound dressings were prepared using cotton fibers reinforced with elastic compression straps and secured with a polyester fabric of tight mesh size. The cotton pads were doped with a wound healing biocomposite, composed of chitosan, glycogen, and ZnO nanoparticles (CG@ZnONPs) previously formulated through a green process. The size of ZnONPs in the prepared CG@ZnONPs was 30-80 nm. The cotton pads impregnated with the CG@ZnONPs nanocomposite were characterized using FTIR, SEM, EDX, TGA, and DTGA methods. Moreover, the prepared dressings were tested on a number of intentionally injured rats. In this experiment, the % contraction of the treated wounds was monitored and compared to that of a control group of wounded rats, to which only sterile gauzes were applied. The results showed a much faster and an almost complete healing of rats treated with the synthesized dressings and the results were further confirmed by histopathological examination. The dressings were also found to exert a significant antimicrobial activity against a number of pathogenic microorganisms, generally encountered in common wounds, and could therefore be recommended to be a novel biomedical application for a fast, successful, and flawless wounds healing process., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study, cotton fabrics based on zinc oxide nanoparticles in situ synthesis, acyclovir, nanochitosan, and clove oil were treated. The treated cotton fabrics were examined by FTIR, HR-TEM, FE-SEM, EDAX, and the surface roughness processing of FE-SEM images. The obtained characterization data emphasized the nano-size of nanocomposite with high homogeneity of particles in spherical shape as well as affirmed the deposition of nanocomposite onto the textile fibers with concluded that the deposition of nanocomposite was increased parallel with sonication time. Antimicrobial and antiviral activities of treated cotton fabrics were evaluated. Results revealed that treated cotton fabrics exhibited promising antibacterial activity toward Gram-positive higher than Gram-negative bacteria. Likewise, treated cotton fabrics are still effective as antibacterial after washing for 100 cycles. Moreover, treated cotton fabrics exhibited potential antifungal activity against Candida albicans, Aspergillus niger, and Aspergillus fumigatus. The antiviral activity significantly depended on the type of virus. The treated cotton fabrics showed antiviral activity against tested viral particles (HSV-1, Adeno, and CoxB2) with viral inhibition of 95.9, 76.4, and 86.9% respectively, while in the case of coated cotton textile with acyclovir, it only exhibited viral inhibition of 49.9, 41, and 22.3% respectively., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Bacterial infectious diseases are serious health problem which extends to economic and social complications. Moreover, bacterial antibiotic resistance, lack of suitable vaccine or emergence of new mutations is forcing the development of novel antimicrobial agents. The objective of this study is to synthesize and characterize star-like zinc oxide nanoparticles for the application of antibacterial activities in cellulose based hygiene products. ZnO NPs were in situ synthesized via precipitation method on the surface of cellulose fibers. Since bactericidal activity of nanoparticles in part depends on the concentration in the growth medium, various amount of ZnO was incorporated into cellulose matrix ranging from 1 to 3 wt%. Microscopic (TEM, SEM) and spectroscopic (FT-IR, XRD) methods were utilized to investigate the final products. The infrared absorption spectra analysis supported by theoretical finding that during the reaction, ZnO nanoparticles could be bonded with cellulose fibers via hydrogen bonding. The yield of functionalization was determined through thermogravimetric analysis. Collected data proved the successful functionalization of the cellulose fibers with nanoparticles. Static contact angle measurements were carried out showing absorptive character of as prepared fabrics. All the samples were tested for the antibacterial properties and the results were compared to the samples prepared from the pristine cellulose fibers. Moreover, mechanical tests were performed revealing that the addition of only 2 wt% of the nanofiller boosted tensile, tearing and bursting strength by a factor of 1.6, 1.4 and 2.2 in comparison to unfunctionalized paper sample, respectively. Fabricated fabric presenting high hydrophilicity and antibacterial properties have gained increased applications in fabric industry, including hygiene product industry and hence the result of this study would be a welcomed option., (© 2022. The Author(s).)

Lignin has been demonstrated to be green and effective for the modification of ZnO-based materials. In this work, quaternized lignin/zinc oxide nanostructured hybrid composites (QLS/ZnO NCs) were synthesized with good dispersion and uniform particle size via a facile hydrothermal method. Sodium lignosulfonate (LS) was modified by quaternization to endow the positive charges, which effectively captured bacteria due to the electrostatic interactions. Interestingly, QLS/ZnO NCs show a litchi-like morphology consisting of nanorods with diameters of 5-10 nm, which further resulted in damage to the bacterial cell membrane. Owing to the surface charge and rough surface topology for bacterial capture, QLS/ZnO NCs exhibited greatly enhanced antibacterial activity compared with bare ZnO. After being treated with QLS/ZnO NCs for 90 min, the sterilization rates of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) reached 97.54% and 99.55%, respectively. Due to the reactive oxygen species (ROS) produced by ZnO under light irradiation, the antibacterial activity of QLS/ZnO NCs could be further enhanced. In addition, the minimal inhibition concentrations (MICs) of QLS/ZnO NCs towards E. coli and S. aureus were both 100 μg/mL, and the minimum bactericidal concentrations (MBCs) were 100 μg/mL and 200 μg/mL, respectively. Moreover, with the incorporation of QLS/ZnO NCs into polyurethane films, the composite films showed excellent antibacterial activity, strong tensile strength and enhanced ultraviolet light blocking performance., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Cellulose nanocrystal (CNC) and ZnO/CuO nanostructure were successfully synthesized by acid hydrolysis and sol-chemical methods, respectively. For the first time, CNC was used as a host polymer for synthesis of CNC/ZnO/CuO through In-situ solution casting technique. Morphological and structural of CNC, ZnO/CuO and hybrid CNC/ZnO/CuO were investigated by TEM, SEM-EDX, FT-IR, XRD and XPS analyses. The analysis revealed that, poly-dispersed, smooth and rod like CNC with an average length of ∼ 85.4 nm, average diameter of ∼13.9 nm and surface charge of 0.01 mmol/gm. As well, irregular shapes as hexagonal, spherical and cluster or star like of ZnO/CuO were formed. EDX and XRD spectra exhibited highly purified CNC/ZnO/CuO and pointed to cellulose II crystallite form with a monoclinic structure. The results demonstrated that, 91.3 % and 99.7 % dye degradation was achieved after 40 min of irradiation due to ZnO/CuO and CNC/ZnO/CuO treatment. Moreover, the inhibition zones formed due to 100 ppm ZnO/CuO were duplicated after integrating CNC (from 7.7:10.3 mm to 14.3:20.3 mm). The hybrid nanostructure exhibit larvicidal activity against Anopheles stephensi better than CNC and ZnO/CuO nanostructures., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The effects of nano-ZnO and nano-SiO 2 on the properties of PVA/xylan composite films were investigated in this work. Results showed that nano-ZnO and nano-SiO 2 could effectively improve the mechanical strength, moisture and oxygen barrier properties and surface hydrophobic property of the composite films. The results of FTIR and XRD indicated the interaction of hydrogen bonds between nanoparticles and PVA and xylan. When the contents of nano-ZnO and nano-SiO 2 in the composite films were 3%, the tensile strength was increased to 20.4 MPa and 22.5 MPa, respectively, while water vapor permeability (3.14 and 3.03 × 10 -11  g·m -1 ·s -1 ·Pa -1 ) and oxygen permeability (5.28 and 5.003 cm 3 ·m -2 ·24 h -1 ·0.1 MPa -1 ) reached the minima. With the increase of nano-ZnO and nano-SiO 2 dosage, the solubility of composite films was increased. When the contents of nano-ZnO and nano-SiO 2 were 3% and 4%, respectively, the contact angles of the films was increased up to 101° and 78°. Besides, the composite films with nano-ZnO exhibited UV shielding performance, whereas the ones with nano-SiO 2 had similar UV light-transparency to the pure PVA/xylan composite films., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Chitosan/silica hybrid was used for zinc oxide (ZnO) nanoparticles immobilization to form chitosan/silica/ZnO nanocomposite. This nanocomposite was utilized to eliminate methylene blue (MB) from wastewater. The effect of ZnO immobilization on the adsorption properties of the nanocomposite was studied in details. The best interpretation for the equilibrium data was given by Langmuir isotherm, and the highest adsorption capacity of MB reached to 293.3 mg/g in slight basic medium. As an effective and low-cost adsorbent, chitosan/silica/ZnO nanocomposite is expected to have a promising future for adsorption of organic dyes from their aqueous solutions., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, various amounts of nanoclay montmorillonite (MMT) and ZnO nanopowders were used to analyze the properties of biodegradable nanocomposites of cationic starch (CS). Nanocomposites are produced by solvent casting method. The structure of CS-MMT nanocomposite films that contain 3% montmorillonite was exfoliated and was proved by XRD test. New hydrogen bonds were successfully formed between the CS hydroxyl groups and nanofillers and this was proved by FTIR test. The water vapor permeability and the UV light transmittance of the nanocomposites reduced after the contents of MMT and ZnO increased. ∆E and opacity of the nanocomposites enhanced after the amount of ZnO increased. Tensile strength (TS) of nanocomposites increased after the incorporation of ZnO and MMT nanoparticles although the elongation at break was diminished. Results showed that the 3 and 0.7 wt% amounts of montmorillonite and ZnO nanopowders were sufficient in order to acquire a well-moderated mechanical behavior in plastic and elastic regions, and they also cause good improvements in barrier and optical properties., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The use of sunscreens is essential for preventing skin damage and the potential appearance of skin cancer in humans. Inorganic active components such as zinc oxide (ZnO) have been used commonly in sunscreens due to their ability to block UVA radiation. This ultraviolet (UV) protection might be enhanced to cover the UVB and UVC bands when combined with other components such as titanium dioxide (TiO2). In this work we evaluate the photoprotection properties of organic nanoparticles made from lignin in combination with ZnO nanoparticles as active ingredients for sunscreens. Lignin nanoparticles were synthesized from Agave tequilana lignin. Two different pulping methods were used for dissolving lignin from agave bagasse. ZnO nanoparticles were synthesized by the precipitation method. All nanoparticles were characterized by SEM, UV-Vis and FT-IR spectroscopy. Nanoparticles were mixed with a neutral vehicle in different concentrations and in-vitro sun protection factor (SPF) values were calculated. Different sizes of spherical lignin nanoparticles were obtained from the spent liquors of two different pulping methods. ZnO nanoparticles resulted with a flake shape. The mixture of all components gave SPF values in a range between 4 and 13. Lignin nanoparticles showed absorption in the UVB and UVC regions which can enhance the SPF value of sunscreens composed only of zinc oxide nanoparticles. Lignin nanoparticles have the added advantage of being of organic nature and its brown color can be used to match the skin tone of the person using it., (Copyright © 2016 Elsevier B.V. All rights reserved.)

This paper describes self-reinforced antibacterial and oil-resistant properties that were successfully prepared by surface selective dissolution of filter paper in a NaOH/Urea/ZnO (weight ratio of 8:12:0.25) aqueous solution. The effect of the processing time on the mechanical properties of this paper was evaluated at -12°C. The paper morphologies were characterized using Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The oil-resistance and antibacterial properties of the produced paper were also investigated. Excellent mechanical properties were observed for an optimized handling time. The tensile and burst strengths of the modified paper were in excess of 100% of the original. Meanwhile, the treated paper was completely oil-resistant within 24 h and demonstrated good antibacterial properties when exposed to Staphylococcus aureus. The traces of residual zinc oxide were found to be safe for food.