Synergistic toxic effects of high-strength ammonia and ZnO nanoparticles on biological nitrogen removal systems and role of exogenous C10-HSL regulation.

The inhibitory effects of zinc oxide nanoparticles (ZnO NPs) and impacts of N-acyl-homoserine lactone (AHL)-based quorum sensing (QS) on biological nitrogen removal (BNR) performance have been well-investigated. However, the effects of ammonia nitrogen (NH4+-N) concentrations on NP toxicity and AHL regulation have seldom been addressed yet. This study consulted on the impacts of ZnO NPs on BNR systems when high NH4+-N concentration was available. The synergistic toxic effects of high-strength NH4+-N (200 mg/L) and ZnO NPs resulted in decreased ammonia oxidation rates and dropped the nitrogen removal efficiencies by 17.5% ± 0.2%. The increased extracellular polymeric substances (EPS) production was observed in response to the high NH4+-N and ZnO NP stress, which indicated the defense mechanism against the toxic effects in the BNR systems was stimulated. Furthermore, the regulatory effects of exogenous N-decanoyl-homoserine lactone (C10-HSL)-mediated QS system on NP-stressed BNR systems were revealed to improve the BNR performance under different NH4+-N concentrations. The C10-HSL regulated the intracellular reactive oxygen species levels, denitrification functional enzyme activities, and antioxidant enzyme activities, respectively. This probably synergistically enhanced the defense mechanism against NP toxicity. However, compared to the low NH4+-N concentration of 60 mg/L, the efficacy of C10-HSL was inhibited at high NH4+-N levels of 200 mg/L. The findings provided the significant application potential of QS system for BNR when facing toxic compound shock threats.

Design of Bionanomaterial of Chitosan Carbohydrate Polymer Composited with Broccoli Extract and Zinc Oxide Nanoparticles: Anticancer Activity in Human Osteosarcoma.

In the current research, a chitosan/broccoli extract/ZnO nanoparticle (CH/BE/ZnO) bionanocomposite was created. The physicochemical properties of CH/BE/ZnO bionanocomposite were investigated using a variety of methods, including field emission scanning electron microscopy (FESEM), elemental analysis (CHN-O), X-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), Brunauer-Emmett-Teller (BET), and transmission electron microscopy (TEM). The CH/BE/ZnO bionanocomposite's biological activity was assessed by examining its cytotoxicity capabilities against a bone cancer cell line (MG63). The total pore volume and specific surface area of CH/BE/ZnO are 0.134 cm3/g and 16.99 m2/g, respectively. The IC50 results for CH/BE/ZnO bionanocomposite in bone cancer investigations using the MTT test against the MG63 cell line was 115 µg/mL. The results indicate that the CH/BE/ZnO bionanocomposite is an effective chemotherapeutic agent against human osteosarcoma. The CH/BE/ZnO bionanocomposite showed high performance and structure, which means innovating nanomaterial agents for biological applications in the future.

Exploring the insights of bioslurry-Nanoparticle amalgam for soil amelioration.

In response to global agricultural challenges, this review examines the synergistic impact of bioslurry and biogenic nanoparticles on soil amelioration. Bioslurry, rich in N, P, K and beneficial microorganisms, combined with zinc oxide nanoparticles synthesized through eco-friendly methods, demonstrates remarkable soil improvement capabilities. Their synergistic effects include enhanced nutrient availability through increased soil enzymatic activities, improved soil structure via stable aggregate formation, stimulated microbial activity particularly beneficial groups, enhanced water retention due to increased organic matter and modified soil surface properties and reduced soil pH fluctuations. These mechanisms significantly impact soil physico-chemical properties including cation exchange capacity, electrical conductivity and nutrient dynamics. This review analyses these effects and their implications for sustainable agricultural practices, focusing on crop yield improvements, reduced chemical fertilizer dependence and enhanced plant stress tolerance. Knowledge gaps such as long-term nanoparticle accumulation effects and impacts on non-target organisms are identified. Future research directions include optimizing bioslurry-nanoparticle ratios for various soil types and developing "smart" nanoparticle-enabled biofertilizers with controlled release properties. This innovative approach contributes to environmentally friendly farming practices, potentially enhancing global food security and supporting sustainable agriculture transitions. The integration of bioslurry and biogenic nanoparticles presents a promising solution to soil degradation and agricultural sustainability challenges.

Molecular mechanisms of zinc oxide nanoparticles neurotoxicity.

Zinc oxide nanoparticles (ZnONPs) are widely used in industry and biomedicine. A growing body of evidence demonstrates that ZnONPs exposure may possess toxic effects to a variety of tissues, including brain. Therefore, the objective of the present review was to summarize existing evidence on neurotoxic effects of ZnONPs and discuss the underlying molecular mechanisms. The existing laboratory data demonstrate that both in laboratory rodents and other animals ZnONPs exposure results in a significant accumulation of Zn in brain and nervous tissues, especially following long-term exposure. As a result, overexposure to ZnONPs causes oxidative stress and cell death, both in neurons and glial cells, by induction of apoptosis, necrosis and ferroptosis. In addition, ZnONPs may induce neuroinflammation through the activation of nuclear factor kappa B (NF-κB), extracellular signal-regulated kinase (ERK), p38 mitogen-activated protein kinase (MAPK), and lipoxygenase (LOX) signaling pathways. ZnONPs exposure is associated with altered cholinergic, dopaminergic, serotoninergic, as well as glutamatergic and γ-aminobutyric acid (GABA)-ergic neurotransmission, thus contributing to impaired neuronal signal transduction. Cytoskeletal alterations, as well as impaired autophagy and mitophagy also contribute to ZnONPs-induced brain damage. It has been posited that some of the adverse effects of ZnONPs in brain are mediated by altered microRNA expression and dysregulation of gut-brain axis. Furthermore, in vivo studies have demonstrated that ZnONPs exposure induced anxiety, motor and cognitive deficits, as well as adverse neurodevelopmental outcome. At the same time, the relevance of ZnONPs-induced neurotoxicity and its contribution to pathogenesis of neurological diseases in humans are still unclear. Further studies aimed at estimation of hazards of ZnONPs to human brain health and the underlying molecular mechanisms are warranted.

Rational Design and Fine Fabrication of Passive Daytime Radiative Cooling Textiles Integrate Antibacterial, UV-Shielding, and Self-Cleaning Characteristics.

Passive daytime radiative cooling (PDRC) textiles hold substantial potential for localized outdoor cooling of the human body without additional energy consumption, but their limited multifunctional integration severely hinders their practical application. Herein, aluminum-doped zinc oxide (AZO) nanoparticles were purposefully introduced into poly(vinylidene fluoride) (PVDF) nanofibers via a facile electrospinning process, forming a large-scale and flexible PDRC textile with the desired antibacterial, UV-shielding, and self-cleaning capabilities. These prepared PDRC textiles present a weighted sunlight reflection rate of 92.3% and a weighted emissivity of 89.5% in the mid-infrared region. Furthermore, outdoor tests with an average solar intensity of ∼715 W/m2 demonstrated that a skin simulator temperature could be cooled by ∼16.1 °C below the ambient temperature, outperforming cotton fabric by ∼6.3 °C. Owing to the outstanding photocatalytic properties of the AZO nanoparticles, these prepared PVDF textiles exhibit antibacterial properties (Escherichia coli: 99.99%), UV-shielding performance (UPF > 50+), and superior self-cleaning capabilities, providing a cost-effective and eco-friendly avenue for daytime personal thermal management.

Enhanced Photocatalytic Performance under Ultraviolet and Visible Light Illumination of ZnO Thin Films Prepared by Modified Sol-Gel Method.

Semiconductor oxides are frequently used as active photocatalysts for the degradation of organic agents in water polluted by domestic industry. In this study, sol-gel ZnO thin films with a grain size in the range of 7.5-15.7 nm were prepared by applying a novel two-step drying procedure involving hot air treatment at 90-95 °C followed by conventional furnace drying at 140 °C. For comparison, layers were made by standard furnace drying. The effect of hot air treatment on the film surface morphology, transparency, and photocatalytic behavior during the degradation of Malachite Green azo dye in water under ultraviolet or visible light illumination is explored. The films treated with hot air demonstrate significantly better photocatalytic activity under ultraviolet irradiation than the furnace-dried films, which is comparable with the activity of unmodified ZnO nanocrystal powders. The achieved percentage of degradation is 78-82% under ultraviolet illumination and 85-90% under visible light illumination. Multiple usages of the hot air-treated films (up to six photocatalytic cycles) are demonstrated, indicating improved photo-corrosion resistance. The observed high photocatalytic activity and good photo-corrosion stability are related to the hot air treatment, which causes a reduction of oxygen vacancies and other defects and the formation of interstitial oxygen and/or zinc vacancies in the films.

One-Dimensional ZnO Nanorod Array Grown on Ag Nanowire Mesh/ZnO Composite Seed Layer for H2 Gas Sensing and UV Detection Applications.

Photodetectors and gas sensors are vital in modern technology, spanning from environmental monitoring to biomedical diagnostics. This paper explores the UV detection and gas sensing properties of a zinc oxide (ZnO) nanorod array (ZNA) grown on silver nanowire mesh (AgNM) using a hydrothermal method. We examined the impact of different zinc acetate precursor concentrations on their properties. Results show the AgNM forms a network with high transparency (79%) and low sheet resistance (7.23 Ω/□). A sol-gel ZnO thin film was coated on this mesh, providing a seed layer with a hexagonal wurtzite structure. Increasing the precursor concentration alters the diameter, length, and area density of ZNAs, affecting their performance. The ZNA-AgNM-based photodetector shows enhanced dark current and photocurrent with increasing precursor concentration, achieving a maximum photoresponsivity of 114 A/W at 374 nm and a detectivity of 6.37 × 1014 Jones at 0.05 M zinc acetate. For gas sensing, the resistance of ZNA-AgNM-based sensors decreases with temperature, with the best hydrogen response (2.71) at 300 °C and 0.04 M precursor concentration. These findings highlight the potential of ZNA-AgNM for high-performance UV photodetectors and hydrogen gas sensors, offering an alternative way for the development of future sensing devices with enhanced performance and functionality.

Zinc oxide nanoparticles reduce cadmium accumulation in hydroponic lettuce (Lactuca sativa L.) by increasing photosynthetic capacity and regulating phenylpropane metabolism.

Due to the continuous production of industrial wastes and the excessive use of chemical fertilizers and pesticides, severe cadmium (Cd) pollution in soil has occurred globally. This study investigated the impacts of incorporating zinc oxide nanoparticles (ZnONPs) into hydroponically grown lettuce (Lactuca sativa) under cadmium stress conditions, to seek effective methods to minimize Cd buildup in green leafy vegetables. The results showed that 1 mg/L of Cd significantly inhibited lettuce growth, decreasing in leaves (29 %) and roots (33 %) biomass. However, when lettuce was exposed to 2.5 mg/L ZnONPs under cadmium stress, the growth, chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), actual photochemical efficiency of PSII (φPSII), and activity of key enzymes in photosynthesis were all significantly enhanced. Furthermore, ZnONPs significantly decreased the accumulation of Cd in lettuce leaves (36 %) and roots (13 %). They altered the subcellular distribution and chemical morphology of Cd in lettuce by modifying the composition of cell walls (such as pectin content) and the levels of phenolic compounds, resulting in a reduction of 27 % in Cd translocation from roots to leaves. RNA sequencing yielded 45.9 × 107 and 53.4 × 107 clean reads from plant leaves and roots in control (T0), Cd (T1), Cd+ZnONPs (T2), and ZnONPs (T3) treatment groups respectively, and 3614 and 1873 differentially expressed genes (DEGs) were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis identified photosynthesis, carbon fixation, and phenylpropanoid metabolism as the main causes of ZnONPs-mediated alleviation of Cd stress in lettuce. Specifically, the DEGs identified included 12 associated with photosystem I, 13 with photosystem II and 23 DEGs with the carbon fixation pathway of photosynthesis. Additionally, DEGs related to phenylalanine ammonia-lyase, caffeoyl CoA 3-O-methyltransferase, peroxidase, 4-coumarate-CoA ligase, hydroxycinnamoyl transferase, and cytochrome P450 proteins were also identified. Therefore, further research is recommended to elucidate the molecular mechanisms by which ZnONPs reduce Cd absorption in lettuce through phenolic acid components in the phenylpropanoid metabolism pathway. Overall, treatments with ZnONPs are recommended to effectively reduce Cd accumulation in the edible portion of lettuce.

In vitro and in vivo efficacy of zinc oxide green nanoparticles against multidrug-resistant Salmonella Typhi.

Antibiotic resistance is an increasing threat, requiring novel therapeutic solutions. Metal nanoparticles e.g., zinc oxide nanoparticles (ZnO NPs) exhibited the potential against many bacterial pathogens. Strains of Salmonella enterica serovar Typhi resistant to ceftriaxone were reported first from Pakistan in 2016. Since then, S. Typhi is a pathogen of concern globally owing to its rapidly emerging resistance potential against many last resort antibiotics. In the present study, in vitro and in vivo antimicrobial activity of ZnO NPs against multidrug resistant (MDR) and extensively drug resistant (XDR) Salmonella Typhi strains from Pakistan was evaluated. Zinc oxide green nanoparticles (ZnO GNPs), synthesized from Aloe vera, were characterized by SEM, XRD, UV-vis and Raman spectroscopy. In vitro antibacterial activity of two different concentrations of ZnO GNPs (7 and 15%) was checked using agar well diffusion method. Further, broth microdilution and time kill assays were performed using the ZnO GNPs. In vivo assays were conducted in BALB/c mice sepsis models. In all the three methods, agar well diffusion assay broth microdilution and time kill assay, different zinc oxide dihydrate precursor concentrations had shown the antibacterial activity. The minimum inhibitory concentration (MIC) of ZnO GNPs nanoparticles against MDR and XDR S. Typhi strains was found as 16 to 64 µg/ml. In vivo experiment has shown a significant decrease in CFU/ml in the mice treated with ZnO GNPs as compared to the control group. Our findings have revealed that ZnO GNPs have significant antibacterial activity against MDR and XDR S. Typhi, both in vitro and in vivo.

A human acellular dermal matrix coated with zinc oxide nanoparticles accelerates tendon repair in patients with hand flexor tendon injuries in zone 5 of the hand.

Introduction: Flexor tendon injuries are common and require surgery. Acellular dermal matrix (ADM) is a natural graft used to repair tissues, though infections represent the primary cause of its therapeutic failure. In this study, zinc oxide nanoparticles (ZnO-NPs) were coated on the ADM in order to add antibacterial potential as well as enhance healing properties. Also, the produced ADM/ZnO-NPs graft was applied to accelerate fifth zone flexor tendon repair following the reconstructive surgery. Methods: Morphological, mechanical, cell viability, and antibacterial tests were performed to evaluate the physical and biological properties of the fabricated ADM/ZnO-NPs graft. For clinical evaluations, 20 patients with a flexor tendon injury in zone 5 were randomly divided into control and treatment with ADM/ZnO-NPs groups (n=10 each). The control group had routine reconstructive surgery, while the other group received the ADM/ZnO- NPs graft during their surgery. Postoperative functional outcomes were evaluated 4, 6, and 8 weeks following the tendon repair surgery according to the Buck-Gramcko II criteria. Results: The ADM/ZnO-NPs had natural derm specifications as well as dense and integrated morphology with intermediate antibacterial properties. According to the Buck- Gramcko II criteria, the postoperative functional outcome scores were significantly higher in the ADM/ZnO-NPs group in comparison with the control group at 4 (P<0.01), 6 (P<0.01), and 8 (P<0.001) weeks after the surgery. Conclusion: The present findings revealed that the ADM/ZnO-NPs graft can accelerate the healing of the damaged tendon without common post-operative functional complications and adhesions following the tendon repair surgery. However, more comprehensive clinical trials are still needed.

Green synthesis of silver and gold-doped zinc oxide nanocomposite with propolis extract for enhanced anticancer activity.

Metal and metal oxide nanocomposites have unique properties and are promising for antibacterial and anticancer applications. In this work, we aimed to highlight the relationship between the biosynthesis ways of silver and gold-doped zinc oxide nanocomposites and their functions as anticancer on cell lines (MCF-7 and HepG2). The propolis was used to biosynthesize four different nanoparticles with the same components, including zinc, gold and silver. The nanocomposites were characterized using various techniques, including ultraviolet-visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy Dispersive X-ray analysis (EDX) and cytotoxicity assays. The result of this study showed that formed nanocomposites have a similar level of Zn, Au, and Ag, ranging from 23-34%, 2-6%, and 2-3%, respectively. In addition, adding the components simultaneously produces the fastest color change, and the fabricated nanoparticles have spherical shapes with different layers. In addition, the prepared nanoparticles influenced the cell viability of the cancer cell lines, with the most effective one when Zn, Au, and Ag were added spontaneously to form a nanocomposite called (All) with IC50 of 24.5 µg/mL for MCF7 cells and 29.1 µg/mL for HepG2 cells. Thus, the study illustrates that the preparation of nanocomposite generated through green synthesis with different methods significantly affects the structure and function and may improve the synthesis of nanocomposite to be developed into an efficacious therapeutic agent for cancers. In addition, this study opens the door toward a novel track in the field of nanocomposites as it links the synthesis with structure and function. Further anti-cancer properties, as well as animal testing are needed for those nanocomposites.

Effects of Dietary Supplementation of Zinc Oxide Quantum Dots on Growth Performance and Gut Health in Broilers.

This study aims to investigate the effect of different levels of zinc oxide quantum dots (ZnO-QDs) on the growth performance and gut health in broilers. A total of 1125 1-day-old Ross 308 broilers were randomly divided into five groups with 15 replicates of 15 chicks each. The broilers were fed basal diets supplemented with 0, 40, 80, 120, or 160 mg Zn/kg as ZnO-QDs for 6 weeks. The results showed that dietary 80 and 120 mg Zn/kg ZnO-QD supplementation increased (P < 0.05) average daily gain (1.4-1.7%) and reduced feed conversion ratio (1.3%) compared to the basal diet group during various experimental periods. Meanwhile, 80 mg Zn/kg ZnO-QD supplementation increased (P < 0.05) trypsin activity (25.4%), villus height, and the ratio of villus height to crypt depth in the jejunum. Moreover, 80 mg Zn/kg ZnO-QD supplementation increased (P < 0.05) the activities of glutathione reductase (47.7%) and superoxide dismutase (30.9%), while 120 mg Zn/kg ZnO-QD supplementation decreased (P < 0.05) glutathione peroxidase activity (27.1%) in the jejunum. Furthermore, 40 mg Zn/kg ZnO-QD supplementation down-regulated (P < 0.05) the expression of genes; interleukin-2, transforming growth factor ß (TGF-ß), Cathelicidin-1, Cathelicidin-2, Cathelicidin-3, and Occludin, while 80-160 mg Zn/kg ZnO-QD supplementation up-regulated (P < 0.05) Claudin-2 expression in the jejunum. In conclusion, dietary ZnO-QD supplementation improved growth performance of broilers potentially by enhancing their intestinal health status. Based on nonlinear regression analysis, the appropriate level of ZnO-QD supplementation would be from 98.2 to 102.5 mg Zn/kg.

Poly(vinyl chloride) Films Incorporated with Antioxidant ZnO-Flavonoid Nanoparticles: A Strategy for Food Preservation.

Antioxidant films were prepared using poly(vinyl chloride) (PVC) incorporated with 0.5% or 1.0% zinc oxide (ZnO)-flavonoid (quercetin or morin) nanoparticles (NPZnO-Q% or NPZnO-M%) via the casting method. NP incorporation within the polymer matrix influenced the structural, morphological, optical, and thermal properties of the PVC-based films, as well as their antioxidant activity as assessed using the DPPH radical scavenging method. Our results indicated that increasing ZnO-flavonoid NP concentration increased films thickness, while reducing ultraviolet light (UV) transmittance but conserving transparency. The presence of NPZnO-Q% or NPZnO-M% improved the surface uniformity and thermal stability of the active films. In terms of antioxidant activity, there was an enhancement in the DPPH radical scavenging capacity (PVC/ZnO-Q1.0% > PVC/ZnO-Q0.5% > PVC/ZnO-M0.5% > PVC/ZnO-M1.0% > PVC), suggesting that the packaging can help protect food from oxidative processes. Therefore, these antioxidant films represent an innovative strategy for using as active food packaging material, especially intended for aiding in quality preservation and extending the shelf life of fatty foods.

Biogenic Zinc Oxide Nanoparticles as a Promising Antibacterial Agent: Synthesis and Characterization.

Nanotechnology has gained popularity in recent years due to its wide-ranging applications within the scientific community. The three main methods for synthesizing nanoparticles are physical, chemical, and biological. However, the adverse effects associated with physical and chemical methods have led to a growing interest in biological methods. Interestingly, green synthesis using plants has gained prominence in developing new treatments for bacterial infections. Zinc oxide nanoparticles (ZnO NPs) produced using environmentally friendly methods are more biocompatible and have potential applications as antibacterial agents in the biomedical field. As a result, this review discusses the green synthesis of ZnO NPs, factors influencing optimal synthesis, characterization techniques, and the antibacterial activity of some plant-mediated ZnO NPs. It also provides a comprehensive and analytical exploration of ZnO NP biosynthesis, the role of phytochemical compounds as reducing and stabilizing agents, the mechanism of action of their antibacterial properties and further highlights the challenges and prospects in this innovative research area.

Utilizing green zinc oxide nanoparticles as a sensing platform for ascorbic acid.

We prepared zinc oxide nanoparticles (ZnO NPs) via a green synthesis and used them for the fluorescence sensing of ascorbic acid (AA). For obtaining these nanoparticles, we used an extract from Batavia lettuce as a reducing agent for zinc acetate in a simple, fast, and environmentally friendly synthesis. The ZnO NPs were characterized by X-ray diffractometry (XRD), ultraviolet-visible spectroscopy (UV-vis), Fourier Transform Infrared spectroscopy (FTIR), scanning electron microscopy (SEM), dynamic light scattering (DLS), thermogravimetric analysis (TGA), photoluminescence, point of zero-charge (pHpzc), and chromaticity studies. We verified that the ZnO NPs had an average diameter of 6 nm, with a wurtzite crystalline structure, and when excited at 320 nm emitted radiation in the blue region. The methodology for AA detection is based on the observed increase in fluorescence of the molecule complex formed on the ZnO NPs surface after 20 min of interaction. The results indicated that the proposed technique of analysis is fast, simple, and highly sensitive, with a detection limit for AA of 5.15 µM. Furthermore, the nanoparticles presented excellent photostability for at least 30 days, and low sensitivity to other biological organic molecules. The green ZnO NPs also exhibited an efficient response to the presence of AA in actual complex samples, suggesting that the platform here proposed can find use in clinical analysis protocols.

Hybrid Zinc Oxide Nanocoating on Titanium Implants: Controlled Drug Release for Enhanced Antibacterial and Osteogenic Performance in Infectious Conditions.

Implant-associated bacterial infections are a primary cause of complications in orthopedic implants, and localized drug delivery represents an effective mitigation strategy. Drawing inspiration from the morphology of desiccated soil, our group has developed an advanced drug-delivery system augmented onto titanium (Ti) plates. This system integrates zinc oxide (ZnO) nanorod arrays with a vancomycin drug layer along with a protective Poly(lactic-co-glycolic acid) (PLGA) coating. The binding between the ZnO nanorods and the drug results in attached drug blocks, isolated by desiccation-like cracks, which are then encapsulated by PLGA to enable sustained drug release. Additionally, the release of zinc ions and the generation of reactive oxygen species (ROS) from the ZnO nanorods enhance the antibacterial efficacy. The antibacterial properties of ZnO nanorod-drug-PLGA system have been validated through both in vitro and in vivo studies. Comprehensive investigations were conducted on the impact of bacterial infections on bone defect regeneration and the role of this drug-delivery system in the healing process. Furthermore, the local immune response was analyzed and the immunomodulatory function of the system was demonstrated. Overall, the findings underscore the superior performance of the ZnO nanorod-drug-PLGA system as an efficient and safe approach to combat implant-associated bacterial infections. STATEMENT OF SIGNIFICANCE: Implant-associated bacterial infections pose a significant clinical challenge, particularly in orthopedic procedures. To address this, we developed an innovative ZnO nanorod-drug-PLGA system for local antibiotic delivery on conventional titanium implants. This system is biodegradable and features a unique desiccation-like structure that enables sustained drug release, along with the active substances released from the ZnO nanorods. In a rat calvarial defect model challenged with S. aureus, our system demonstrated remarkable antibacterial efficacy, significantly enhanced bone defect regeneration, and exhibited local immunomodulatory effects that support both infection control and osteogenesis. These breakthrough findings highlight the substantial clinical potential of this novel drug delivery system and introduce a transformative coating strategy to enhance the functionality of traditional metallic biomaterials.

Effects of Zinc Oxide Nanoparticles (ZnO NPs) on Growth, Immune Responses and Histopathological Alterations in Asian Seabass (Lates calcarifer, Bloch 1790) under Low-Salinity Conditions.

In the present study, Asian seabass (Lates calcarifer, Bloch) fingerings were used as an animal model to investigate the toxicological effects of zinc oxide nanoparticles (ZnO NPs) under 5 ppt estuarine conditions. The fish were exposed to 0, 1, 5 or 50 ppm ZnO NPs for 8 weeks. It was found that ZnO NP concentrations of 5-50 ppm negatively affected several growth rate parameters, such as the weight and total length of the fish. Additionally, 5 and 50 ppm ZnO NPs led to 32.55% and 100% mortality, respectively, after 8 weeks after exposure (WAE). Furthermore, compared with the control, exposure to 1-50 ppm ZnO NPs strongly affected hematological indices, such as total blood cells, red blood cells, leukocytes and hematocrit, and suppressed lysozyme activity, superoxide anion production and bactericidal activity. High Zn concentrations accumulated in the head kidney, gills and liver, whereas low levels were detected in the gut, skin and muscle. Expression analysis of immune-related genes via quantitative real-time RT-PCR revealed that 5 and 50 ppm ZnO NPs significantly upregulated the cc and cd4 genes at 1 WAE. In contrast, 50 ppm ZnNPs downregulated the expression levels of the cd8, cc, hsp70, hsp90, tcrα, lyz and igmh genes at 1 WAE (p < 0.05). Finally, at 8 WAE, histopathological analysis revealed that 5 and 50 ppm ZnO NPs severely induced alterations in the head kidney, gills and liver.

Novel Synthesis of Zinc Oxide on Cotton Fabric by Cathodic Cage Plasma Deposition for Photocatalytic and Antibacterial Performance.

Cotton fabrics with zinc oxide (ZnO) coating are of significant interest due to their excellent antibacterial performance. Thus, they are widely in demand in the textile industry due to their medical and hygienic properties. However, conventional techniques used to deposit ZnO on fabric require long processing times in deposition, complex and expensive equipment, and multiple steps for deposition, such as a separate process for nanoparticle synthesis and subsequent deposition on fabric. In this study, we proposed a new method for the deposition of ZnO on fabric, using cathodic cage plasma deposition (CCPD), which is commonly used for coating deposition on conductor materials and is not widely used for fabric due to the temperature sensitivity of the fabric. The effect of gas composition, including argon and a hydrogen-argon mixture, on the properties of ZnO deposition is investigated. The deposited samples are characterized by XRD, SEM, EDS, photocatalytic, and antibacterial performance against Staphylococcus aureus and Pseudomonas aeruginosa bacteria. It is observed that ZnO-deposited cotton fabric exhibits excellent photocatalytic degradation of methylene blue and antibacterial performance, specifically when a hydrogen-argon mixture is used in CCPD. The results demonstrate that CCPD can be used effectively for ZnO deposition on cotton fabric; this system is already used in industrial-scale applications and is thus expected to be of significant interest to garment manufacturers and hospitals.

Cu-ZnO Embedded in a Polydopamine Shell for the Generation of Antibacterial Surgical Face Masks.

A new easy protocol to functionalize the middle layer of commercial surgical face masks (FMs) with Zn and Cu oxides is proposed in order to obtain antibacterial personal protective equipment. Zinc and copper oxides were synthesized embedded in a polydopamine (PDA) shell as potential antibacterial agents; they were analyzed by XRD and TEM, revealing, in all the cases, the formation of metal oxide nanoparticles (NPs). PDA is a natural polymer appreciated for its simple and rapid synthesis, biocompatibility, and high functionalization; it is used in this work as an organic matrix that, in addition to stabilizing NPs, also acts as a diluent in the functionalization step, decreasing the metal loading on the polypropylene (PP) surface. The functionalized middle layers of the FMs were characterized by SEM, XRD, FTIR, and TXRF and tested in their bacterial-growth-inhibiting effect against Klebsiella pneumoniae and Staphylococcus aureus. Among all functionalizing agents, Cu2O-doped-ZnO NPs enclosed in PDA shell, prepared by an ultrasound-assisted method, showed the best antibacterial effect, even at low metal loading, without changing the hydrophobicity of the FM. This approach offers a sustainable solution by prolonging FM lifespan and reducing material waste.

Ternary TiO2/MoS2/ZnO hetero-nanostructure based multifunctional sensing devices.

Novel sensing applications benefit from multifunctional nanomaterials responsive to various external stimuli such as mechanics, electricity, light, humidity, or pollution. While few such materials occur naturally, the careful design of synergized nanomaterials unifies the cross-coupled properties which are weak or absent in single-phase materials. In this study, 2D MoS2 integrated with ultrathin dielectric oxide layers forms hetero-nanostructures with significant impacts on carrier transport. The ternary TiO2/MoS2/ZnO hetero-nanostructures, along with their individual properties, improve the performance of multifunctional sensing devices. The synthesized hetero-nanostructure exhibits a responsivity of up to 16 mA/W to 700 nm light and responds to 5 ppm ammonia gas at room temperature. These enhancements are attributed to interface charge transfer and photogating effects. The ternary TiO2/MoS2/ZnO hetero-nanostructure is compatible with existing semiconductor fabrication technologies, making it feasible to integrate into flexible, lightweight semiconductor devices and circuits. These results may inspire new photodetectors and sensing devices based on two-dimensional (2D) layered materials for IoT applications.