Bioinspired Synthesis and Characterization of Dual-Function Zinc Oxide Nanoparticles from Saccharopolyspora hirsuta: Exploring Antimicrobial and Anticancer Activities.

Microbial synthesis offers a sustainable and eco-friendly approach for nanoparticle production. This study explores the biogenic synthesis of zinc oxide nanoparticles (ZnO-NPs) utilizing the actinomycete Saccharopolyspora hirsuta (Ess_amA6) isolated from Tapinoma simrothi. The biosynthesized ZnO-NPs were characterized using various techniques to confirm their formation and properties. UV-visible spectroscopy revealed a characteristic peak at 372 nm, indicative of ZnO-NPs. X-ray diffraction (XRD) analysis confirmed the crystalline structure of the ZnO-NPs as hexagonal wurtzite with a crystallite size of approximately 37.5 ± 13.60 nm. Transmission electron microscopy (TEM) analysis showed the presence of both spherical and roughly hexagonal ZnO nanoparticles in an agglomerated state with a diameter of approximately 44 nm. The biogenic ZnO-NPs exhibited promising biomedical potential. They demonstrated selective cytotoxic activity against human cancer cell lines, demonstrating higher efficacy against Hep-2 cells (IC50 = 73.01 µg/mL) compared to MCF-7 cells (IC50 = 112.74 µg/mL). Furthermore, the biosynthesized ZnO-NPs displayed broad-spectrum antimicrobial activity against both Pseudomonas aeruginosa and Staphylococcus aureus with clear zones of inhibition of 12.67 mm and 14.33 mm, respectively. The MIC and MBC values against P. aeruginosa and S. aureus ranged between 12.5 and 50 µg/mL. These findings suggest the potential of S. hirsuta-mediated ZnO-NPs as promising biocompatible nanomaterials with dual applications as antimicrobial and anticancer agents.

Changes in the Aggregation Behaviour of Zinc Oxide Nanoparticles Influenced by Perfluorooctanoic Acid, Salts, and Humic Acid in Simulated Waters.

The increasing utilization of zinc oxide nanoparticles (ZnO-NPs) in many consumer products is of concern due to their eventual release into the natural environment and induction of potentially adverse impacts. The behaviour and environmental impacts of ZnO-NPs could be altered through their interactions with environmentally coexisting substances. This study investigated the changes in the behaviour of ZnO-NPs in the presence of coexisting organic pollutants (such as perfluorooctanoic acid [PFOA]), natural organic substances (i.e., humic acid [HA]), and electrolytes (i.e., NaCl and CaCl2) in simulated waters. The size, shape, purity, crystallinity, and surface charge of the ZnO-NPs in simulated water after different interaction intervals (such as 1 day, 1 week, 2 weeks, and 3 weeks) at a controlled pH of 7 were examined using various characterization techniques. The results indicated alterations in the size (such as 162.4 nm, 1 day interaction to >10 µm, 3 weeks interaction) and zeta potential (such as -47.2 mV, 1 day interaction to -0.2 mV, 3 weeks interaction) of the ZnO-NPs alone and when PFOA, electrolytes, and HA were present in the suspension. Different influences on the size and surface charge of the nanoparticles were observed for fixed concentrations (5 mM) of the different electrolytes. The presence of HA-dispersed ZnO-NPs affected the zeta potential. Such dispersal effects were also observed in the presence of both PFOA and salts due to their large aliphatic carbon content and complex structure. Cation bridging effects, hydrophobic interactions, hydrogen bonding, electrostatic interactions, and van der Waals forces could be potential interaction forces responsible for the adsorption of PFOA. The presence of organic pollutants (PFOA) and natural organic substances (HA) can transform the surface characteristics and fate of ZnO-NPs in natural and sea waters.

Highly Transmittance, Mechanical, Thermally Stable Silver Nanowires Network Using ZnO Nanoparticles.

This research addresses challenges with silver nanowires (Ag NWs) as transparent conductive electrodes (TCEs) and heaters in commercial devices. Here, zinc oxide nanoparticles (ZnO NPs) are first reported as a protective layer for Ag NWs. Multi-physics simulations confirm enhanced thermal stability due to improved heat dissipation, temperature distribution, and thermal conductivity from ZnO. When Ag NWs are surrounded by air, heat transfers mainly through convection and radiation because of air's low conduction coefficient. Encasing Ag NWs in ZnO enhances heat transfer to the ZnO surface, accelerating cooling and dissipating more heat into the atmosphere via convection. The results show composite's efficiency in the Joule effect, maintaining a consistent temperature of 78 °C for 700 s after 500 bending cycles, a significant improvement over Ag NWs operating for only 5 s at 80 °C. Additionally, the composite film exhibited exceptional performance, including a sheet resistance of 9.8 Ω sq-1 and an optical transmittance of 96.96 %, outperforming Ag NWs, which have a sheet resistance of 12 Ω sq-1 and a transmittance of 94.11%. The combination of enhanced electrical, thermal, and mechanical stability, along with impressive optical properties, makes Ag NWs/ZnO NPs a promising candidate for transparent conductive electrode materials in various applications.

Low-dose zinc oxide nanoparticles trigger the growth and biofilm formation of Pseudomonas aeruginosa: a hormetic response.

INTRODUCTION: Hormesis describes an inverse dose-response relationship, whereby a high dose of a toxic compound is inhibitory, and a low dose is stimulatory. This study explores the hormetic response of low concentrations of zinc oxide nanoparticles (ZnO NPs) toward Pseudomonas aeruginosa. METHOD: Samples of P. aeruginosa, i.e. the reference strain, ATCC 27,853, together with six strains recovered from patients with cystic fibrosis, were exposed to ten decreasing ZnO NPs doses (0.78-400 µg/mL). The ZnO NPs were manufactured from Peganum harmala using a chemical green synthesis approach, and their properties were verified utilizing X-ray diffraction and scanning electron microscopy. A microtiter plate technique was employed to investigate the impact of ZnO NPs on the growth, biofilm formation and metabolic activity of P. aeruginosa. Real-time polymerase chain reactions were performed to determine the effect of ZnO NPs on the expression of seven biofilm-encoding genes. RESULT: The ZnO NPs demonstrated concentration-dependent bactericidal and antibiofilm efficiency at concentrations of 100-400 µg/mL. However, growth was significantly stimulated at ZnO NPs concentration of 25 µg/mL (ATCC 27853, Pa 3 and Pa 4) and at 12.5 µg/mL and 6.25 µg/mL (ATCC 27853, Pa 2, Pa 4 and Pa 5). No significant positive growth was detected at dilutions < 6.25 µg/mL. similarly, biofilm formation was stimulated at concentration of 12.5 µg/mL (ATCC 27853 and Pa 1) and at 6.25 µg/mL (Pa 4). At concentration of 12.5 µg/mL, ZnO NPs upregulated the expression of LasB ( ATCC 27853, Pa 1 and Pa 4) and LasR and LasI (ATCC 27853 and Pa 1) as well as RhII expression (ATCC 27853, Pa 2 and Pa 4). CONCLUSION: When exposed to low ZnO NPs concentrations, P. aeruginosa behaves in a hormetic manner, undergoing positive growth and biofilm formation. These results highlight the importance of understanding the response of P. aeruginosa following exposure to low ZnO NPs concentrations.

Comparative Evaluation of Cytotoxicity of Zinc Oxide Nanoparticles Mixed With Herbal Extract as an Intracanal Medicament: A Zebrafish Model Study.

Objective In this study, zebrafish embryos are used to study the cytotoxic effects of a novel intracanal medication (ICM) based on zinc oxide nanoparticles (ZnO NPs) loaded with polyherbal extracts (Azadirachta indica and Solanum xanthocarpum). Material and methods In the present study, a green and sustainable method was employed for the synthesis of ZnO NPs mixed with bark and seed extracts of Azadirachta indica and Solanum xanthocarpum to be used as a polyherbal ICM. Formulation of ZnO NPs was confirmed with color change in mixture produced upon dissolving zinc acetate dihydrate in distilled water followed by slow addition of sodium hydroxide solution and herbal extracts. The effects of these green synthesized ZnO NPs were evaluated through a zebrafish embryo toxicity test. Embryos were exposed to different concentrations (25, 50, and 100 µg/mL) of synthesized experimental doses of ZnO NP and compared with the control embryos. Toxicological endpoints, such as the zebrafish embryo's survival rate, hatching rate, and heart rate, were noted and described. Results A concentration-dependent increase in mortality rate and hatching delay followed by declined heart rate was observed in green synthesized ZnO NP-treated embryos. The maximum toxicity was observed with an increase in the concentration of 100 µg/mL of the experimental dose, and at a low concentration of 25 µg/mL, it does not effectively show any developmental alteration in zebrafish embryos. Conclusion A novel polyherbal ICM loaded with ZnO NPs exhibited a dose-dependent effect on the heart rate, hatching, and mortality rate of the embryos. At optimal concentrations, the medication demonstrated minimal developmental malformations and cytotoxic effects, indicating its safety for use. However, increasing concentrations of the medication resulted in severe developmental malformations.

Acrylamide-targeting renal miR-21a-5p/Fibrotic and miR122-5p/ inflammatory signaling pathways and the role of a green approach for nano-zinc detected via in silico and in vivo approaches.

Introduction: Any disruption in renal function can have cascading effects on overall health. Understanding how a heat-born toxicant like acrylamide (ACR) affects kidney tissue is vital for realizing its broader implications for systemic health. Methods: This study investigated the ACR-induced renal damage mechanisms, particularly focusing on the regulating role of miR-21a-5p/fibrotic and miR-122-5p/inflammatory signaling pathways via targeting Timp-3 and TP53 proteins in an In silico preliminary study. Besides, renal function assessment, oxidative status, protein profile, and the expression of renal biomarkers (Timp-1, Keap-1, Kim-1, P53, TNF-α, Bax, and Caspase3) were assessed in a 60-day experiment. The examination was additionally extended to explore the potential protective effects of green-synthesized zinc oxide nanoparticles (ZNO-MONPs). A four-group experiment including control, ZNO-MONPs (10 mg/kg b.wt.), ACR (20 mg/kg b.wt.), and ZNO-MONPs + ACR was established encompassing biochemical, histological, and molecular levels. The study further investigated the protein-binding ability of ZNO and MONPs to inactivate caspase-3, Keap-1, Kim-1, and TNFRS-1A. Results: ZNO-MONPs significantly reduced ACR-induced renal tissue damage as evidenced by increased serum creatinine, uric acid, albumin, and oxidative stress markers. ACR-induced oxidative stress, apoptosis, and inflammationare revealed by biochemical tests, gene expression, and the presence of apoptotic nuclei microscopically. Also, molecular docking revealed binding affinity between ACR-BCL-2 and glutathione-synthetase, elucidating the potential mechanisms through which ACR induces renal damage. Notably, ZNO-MONPs revealed a protective potential against ACR-induced damage. Zn levels in the renal tissues of ACR-exposed rats were significantly restored in those treated with ACR + ZNO-MONPs. In conclusion, this study establishes the efficacy of ZNO-MONPs in mitigating ACR-induced disturbances in renal tissue functions, oxidative stress, inflammation, and apoptosis. The findings shed light on the potential renoprotective activity of green-synthesized nanomaterials, offering insights into novel therapeutic approaches for countering ACR-induced renal damage.

Ferula latisecta gels for synthesis of zinc/silver binary nanoparticles: antibacterial effects against gram-negative and gram-positive bacteria and physicochemical characteristics.

This study explores the potential antibacterial applications of zinc oxide nanoparticles (ZnO NPs) enhanced with silver (Ag) using plant gel (ZnO-AgO NPs). The problem addressed is the increasing prevalence of pathogenic bacteria and the need for new, effective antimicrobial agents. ZnO NPs possess distinctive physicochemical properties that enable them to selectively target bacterial cells. Their small size and high surface area-to-volume ratio allow efficient cellular uptake and interaction with bacterial cells. In this study, the average size of the synthesized ZnO-Ag nanoparticles was 77.1 nm, with a significant standard deviation of 33.7 nm, indicating a wide size distribution. The nanoparticles demonstrated remarkable antibacterial efficacy against gram-negative and gram-positive bacteria, with inhibition zones of 14.33 mm for E. coli and 15.66 mm for B. subtilis at a concentration of 300 µg/ml. Minimum inhibitory concentrations (MIC) were determined to be 100 µg/ml for E. coli and 75 µg/ml for S. saprophyticus. Additionally, ZnO-Ag NPs exhibited excellent biocompatibility, making them appropriate for various pharmacological uses. This study utilizes Ferula latisecta gels, offering a sustainable and eco-friendly approach to nanoparticle synthesis. Incorporating of Ag into ZnO NPs significantly enhances their antimicrobial properties, with the combined results showing great inhibition effects on pathogenic microbes. The findings suggest that ZnO-Ag NPs could be a promising candidate for addressing the challenges posed by drug-resistant bacterial infections and enhancing antimicrobial treatments.

Toxicity of zinc oxide nanoparticles: Cellular and behavioural effects.

Due to their extensive use, the release of zinc oxide nanoparticles (ZnO NP) into the environment is increasing and may lead to unintended risk to both human health and ecosystems. Access of ZnO NP to the brain has been demonstrated, so their potential toxicity on the nervous system is a matter of particular concern. Although evaluation of ZnO NP toxicity has been reported in several previous studies, the specific effects on the nervous system are not completely understood and, particularly, effects on genetic material and on organism behaviour are poorly addressed. We evaluated the potential toxic effects of ZnO NP in vitro and in vivo, and the role of zinc ions (Zn2+) in these effects. In vitro, the ability of ZnO NP to be internalized by A172 glial cells was verified, and the cytotoxic and genotoxic effects of ZnO NP or the released Zn2+ ions were addressed by means of vital dye exclusion and comet assay, respectively. In vivo, behavioural alterations were evaluated in zebrafish embryos using a total locomotion assay. ZnO NP induced decreases in viability of A172 cells after 24 h of exposure and genetic damage after 3 and 24 h. The involvement of the Zn2+ ions released from the NP in genotoxicity was confirmed. ZnO NP exposure also resulted in decreased locomotor activity of zebrafish embryos, with a clear role of released Zn2+ ions in this effect. These findings support the toxic potential of ZnO NP showing, for the first time, genetic effects on glial cells and proving the intervention of Zn2+ ions.

An In Vitro Study of Antioxidant, Anti-inflammatory, and Cytotoxic Effects of Echinacea-Mediated Zinc Oxide Nanoparticles.

Background Plant extracts, such as Echinacea, are preferred in the pharmaceutical industry for their natural availability and minimal adverse effects. Echinacea is known for its anti-inflammatory and other biological properties. Zinc oxide nanoparticles (ZnONPs) are cost-effective, safe, and easily synthesized, making them prominent in nanoparticle research. This study aims to determine the anti-inflammatory, cytotoxic, and antioxidant properties of ZnONPs synthesized using Echinacea. Methodology In this study, 5 mg of powdered Echinacea was mixed with 100 mL of distilled water, heated at 44°C until vaporization, cooled, and filtered twice. The extract was mixed with 0.1 g of zinc oxide and exposed to sunlight for two weeks for nanoparticle synthesis. After centrifugation at 3,500 rpm for eight minutes, nanoparticles were collected. Scanning electron microscope analysis was done to determine nanoparticle formation. Cytotoxicity analysis was conducted using the brine shrimp method, with surviving nauplii counted after exposure to different nanoparticle concentrations. Antioxidant activity was assessed via 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric-reducing antioxidant power (FRAP) assay. Anti-inflammatory activity was assessed using membrane stabilization assay and bovine serum albumin (BSA) assay. Using SPSS Statistics Version 23 (IBM Corp., Armonk, NY, USA), the mean and standard deviation between the prepared extract and the standard were compared for all assays. Results In the cytotoxicity assessment, at 5 µL, the mortality of nauplii remained unchanged from the control. However, at 10 and 20 µL, a 10% increase in mortality was observed, which then stabilized at 40 and 80 µL with 20%. Regarding antioxidant activity, as nanoparticle concentration increased from 10 to 50 µL in the DPPH and FRAP assays, their effectiveness also increased accordingly. According to the anti-inflammatory assay, the membrane stabilization and BSA assay showed an increase in activity with increasing concentrations of 10 to 50 µL extract against similar concentrations of standard diclofenac sodium. Conclusions Echinacea-based ZnONPs demonstrated effective antioxidant and anti-inflammatory properties with low cytotoxicity, suggesting their potential use in future pharmaceutical or therapeutic applications.

Incorporation of Nano-Zinc Oxide as a Strategy to Improve the Barrier Properties of Biopolymer-Suberinic Acid Residues Films: A Preliminary Study.

Finishing coatings in the wood-based composites industry not only influence the final appearance of the product but also serve to protect against fungi and molds and reduce the release of harmful substances, particularly formaldehyde and volatile organic compounds (VOCs). Carbon-rich materials, such as those derived from birch bark extraction, specifically suberin acids, can fulfill this role. Previous research has demonstrated that adding suberin acid residues (SAR) at 20% and 50% by weight significantly enhances the gas barrier properties of surface-finishing materials based on poly(lactide) (PLA) and polycaprolactone (PCL), particularly in terms of total VOC (TVOC) and formaldehyde emissions. This study aims to explore whether these properties can be further improved through the incorporation of nano-zinc oxide (nano-ZnO). Previous research has shown that these nanoparticles possess strong resistance to biological factors and can positively affect the characteristics of nanofilms applied as surface protection. The study employed PLA and PCL finishing layers blended with SAR powder at 10% w/w and included 2% and 4% nano-zinc oxide nanoparticles. The resulting blends were milled to create a powder, which was subsequently pressed into 1 mm-thick films. These films were then applied to raw particleboard surfaces. TVOC and formaldehyde emission tests were conducted. Additionally, the fungal resistance of the coated surfaces was assessed. The results showed that PLA/SAR and PCL/SAR composites with the addition of nano-zinc oxide nanoparticles exhibited significantly improved barrier properties, offering a promising avenue for developing biodegradable, formaldehyde-free coatings with enhanced features in the furniture industry. Furthermore, by utilizing SAR as a post-extraction residue, this project aligns perfectly with the concept of upcycling.

The effect of the combined application of elicitors to Salvia virgata Jacq. under salinity stress on physiological and antioxidant defense.

Salinity stress is one of the most important stress barriers to crop production worldwide. Developing and implementing new strategies against salinity stress is critical for increasing agricultural productivity and supporting sustainable farming. Elicitors such as nanoparticles and Salicylic acid have recently been used potentially for better product yield. Therefore, in our research the Salvia virgata plant was exposed to salinity (NaCl) stress, and zinc oxide nanoparticles (ZnONP), salicylic acid (SA), and the ZnONP + SA combination were applied to plants divided into different groups. While salinity stress decreased the amount of chlorophyll a, chlorophyll b, and carotenoid pigments, SA, ZnONP, and SA + ZnONP elicitors combined with salinity stress enhanced the content of all three pigments. While salt stress raised MDA, H2O2, total phenolic, total flavonoid, soluble sugar and proline content, elicitor applications enhanced proline, soluble sugar, total phenolic and total flavonoid content more. Additionally, the application of NaCl + SA + ZnONP increased proline content by 21.55% and sugar content by 15.73% compared to NaCl application, while decreasing MDA content by 42.28% and H2O2 levels by 42.34%, thereby alleviating the plant's salt stress. It was revealed that DPPH, ABTS, and CUPRAC antioxidant activity sequence used to determine the total antioxidant activity displayed similarities, and it was found as NaCI + ZnONP > NaCI + SA > NaCI + SA + ZnONP > NaCI > Control. Furthermore, all elicitor applications increased CAT, GR, APX, and SOD enzyme activities while reducing oxidative stress in S. virgata plants. When all the data were evaluated, it was confirmed that SA and ZnONP had a synergistic effect and that SA and ZnONP have the potential to support plant development and growth under salinity. SA and ZnONP applications may have the capacity to least the detrimental impacts of salinity stress on plants. However, further research is needed to investigate the effectiveness of SA and ZnONPs in ameliorating salinity or different stress factors in various other plants.

Formulation, preparation of niosome loaded zinc oxide nanoparticles and biological activities.

In this study, zinc oxide nanoparticles (Zn-NPs) were prepared by the green synthesis method and loaded inside niosomes as a drug release system and their physicochemical and biological properties were determined. Zn-NPs were prepared by the eco-friendly green strategy, the structure, and morphological properties were studied and loaded into niosomes. Subsequently, different formulations of niosomes containing Zn-NPs were prepared and the optimal formulation was used for biological studies. Scanning electron microscope (SEM) and dynamic light scattering (DLS) were used to investigate the morphology and size of nanoparticles. Fourier transform infrared spectroscopy (FTIR) and UV-Vis were used to confirm the synthesis of Zn-NPs. Energy dispersive X-ray spectrometer (EDS) determined the elemental analysis of the Zn-NPs synthesis solution and the crystalline structure of Zn-NPs was analysed by XRD (X-Ray diffraction). Furthermore, Zn-NPs were loaded inside the niosomes, and their structural characteristics, entrapment efficiency (EE%), the release profile of Zn-NPs, and their stability also were assessed. Moreover, its antimicrobial properties against some microbial pathogens, its effect on the expression of biofilm genes, and its anticancer activity on the breast cancer cell lines were also determined. To study the cytocompatibility, exposure of niosomes against normal HEK-293 cells was carried out. In addition, the impact of niosomes on the expression of genes involved in the apoptosis (Bcl2, Casp3, Casp9, Bax) at the mRNA level was measured. Our findings revealed that the Zn-NPs have a round shape and an average size of 27.60 nm. Meanwhile, UV-Vis, FTIR, and XRD results confirmed the synthesis of Zn-NPs. Also, the EE% and the size of the optimized niosomal formulation were 31.26% and 256.6 ± 12 nm, respectively. The release profile showed that within 24 h, 26% of Zn-NPs were released from niosomes, while in the same period, 99% of free Zn-NPs were released, which indicates the slow release of Zn-NPs from niosomes. Antimicrobial effects exhibited that niosomes containing Zn-NPs had more significant antimicrobial and anti-biofilm effects than Zn-NPs alone, the antimicrobial and anti-biofilm effects increased 2 to 4 times. Cytotoxic effects indicated that when Zn-NPs are loaded into niosomes, the anticancer activity increases compared to Zn-NPs alone and has low cytotoxicity on cancer cells. Niosomes containing ZnNPs increased the apoptosis-related gene expression level and reduced the Bcl2 genes. In general, the results show that niosomes can increase the biological effects of free Zn-NPs and therefore can be a suitable carrier for targeted delivery of Zn-NPs.

Zinc Oxide Nanoparticles Attenuated Neurochemical and Histopathological Alterations Associated with Aluminium Chloride Intoxication in Rats.

The present investigation explored the potential neuroprotective role of zinc oxide nanoparticles (ZnONPs) on aluminum chloride (AlCl3)-mediated Alzheimer's disease (AD)-like symptoms. Rats were distributed into four treatment groups equally: control, ZnONPs (4 mg/kg b.wt.), AlCl3 (100 mg/kg b.wt.), and ZnONPs + AlCl3 groups. Rats were treated for 42 consecutive days. ZnONPs injection into AlCl3-treated rats suppressed the development of oxidative challenge in the cortical and hippocampal tissues, as demonstrated by the decreased neuronal pro-oxidants (malondialdehyde and nitric oxide), and the increased glutathione and catalase levels. Additionally, ZnONPs injection showed anti-inflammatory potency in response to AlCl3 by decreasing levels of tumor necrosis factor-α and interleukin-1ß. Moreover, pretreatment with ZnONPs prevented neuronal cell loss by decreasing the level of pro-apoptotic caspase-3 and enhancing the anti-apoptotic B cell lymphoma 2. Furthermore, ZnONPs ameliorated the disturbed acetylcholinesterase activity, monoamines (norepinephrine, dopamine, and serotonin), excitatory (glutamic and aspartic acids), and inhibitory amino acids (GABA and glycine) in response to AlCl3 exposure. These findings indicate that ZnONPs may have the potential as an alternative therapy to minimize or prevent the neurological deficits in AD model by exhibiting antioxidative, anti-inflammation, anti-apoptosis, and neuromodulatory effects.

Green reduction of ZnO nanoparticles using cationic dialdehyde cellulose (cDAC) for efficient Congo red dye removal.

More sustainable materials have been becoming an important concern of worldwide scientists, and cellulosic materials are one alternative in water decontamination. An efficient strategy to improve removal capacity is functionalizing or incorporating nanomaterials in cellulose-based materials. The new hybrid cDAC/ZnONPs was produced by green synthesis of zinc oxide nanoparticles (ZnONPs), promoting the in situ reduction and immobilization on the cationic dialdehyde cellulose microfibers (cDAC) surface to remove Congo red dye from water. cDAC/ZnONPs was characterized by scanning electron microscopy (SEM-EDS) and infrared spectroscopy (FTIR), which showed efficient nanoparticles reduction. Adsorption efficiency on cationic cellulose surface was investigated by pH, contact time, initial concentration, and dye selectivity tests. The material followed the H isotherm model, which resulted in a maximum adsorption capacity of 1091.16 mg/g. Herein, was developed an efficient and ecologically correct new adsorbent, highly effective in Congo red dye adsorption even at high concentrations, suitable for the remediation of contaminated industrial effluents.

[Effect of zinc oxide nanoparticles on hypoxia and pyroptosis of rat neutrophils].

Objective: To investigate the effects of zinc oxide nanoparticles (ZnO-NPs) on neutrophil hypoxia and pyroptosis through nucleotide binding of oligomeric domain-like receptor protein 3 (NLRP3) inflammasome, and to analyze the role of pyroptosis on respiratory tract inflammotion induced by ZnO-NPs. Methods: In October 2022, primary cultured neutrophils were obtained from the abdominal aortic blood of SPF adult healthy SD rats. The neutrophils were treated with ZnO-NPs solution (0, 5, 10, 20 µg/ml) at different concentrations, and hypoxia group (5% O(2)) was set up. Hypoxia and reactive oxygen species (ROS) levels were detected by flow cytometry, and the expression levels of NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), cleaved Caspase-1 were measured by Western blot. The activity of lactic dehydrogenase (LDH) in the cell supernatant was measured by coloration, and the content of interleukin-1 beta (IL-1ß) in cell culture supernatant was detected by enzyme-linked immunosorbent assay (ELISA) . Results: Compared with the control group, hypoxia and ROS levels of neutrophils in hypoxia group and ZnO-NPs groups were significantly increased (P<0.05), and NLRP3, ASC, cleaved Caspase-1 protein expression levels, LDH activity and IL-1ß content were significantly increased (P<0.05). Compared with hypoxia group, hypoxia and ROS levels of neutrophils in 5 µg/ml and 10 µg/ml ZnO-NPs groups were significantly decreased (P<0.05), NLRP3, ASC, cleaved Caspase-1 protein expression levels, LDH activity, and IL-1ß content were decreased significantly (P<0.05). There were no significant differences in hypoxia, ROS levels, ASC, cleaved Caspase-1 protein expression levels, LDH activity, and IL-1ß content between the 20 µg/ml ZnO-NPs group and the hypoxia group (P>0.05) . Conclusion: ZnO-NPs treatment may activate the NLRP3 inflammasome to induce pyroptosis of neutrophils which may be related to ROS and hypoxia.

Zinc oxide nanoparticles derived from Penicillium griseofulvum mitigate DMBA/TPA-promoted mice skin carcinogenesis by modulating NF-ĸB associated signalling.

This study investigates the synthesis of zinc oxide nanoparticles using Penicillium griseofulvum (ZnONPs-PG) and their potential role in preventing DMBA/TPA-induced skin cancer. The synthesis process involved using a 1-mM zinc acetate dihydrate as a precursor in P. griseofulvum. Various analytical techniques, including FTIR spectroscopy, UV-Vis, TEM, XRD, and DLS, were utilized to characterize the ZnONPs. The efficacy of ZnONPs-PG was then evaluated in a DMBA/TPA-induced skin cancer model. Mice were treated topically with DMBA/TPA in acetone (200 µL) over 2 weeks, with treatments continuing for 20 weeks. Results showed 100% tumor occurrence, histological changes, elevated lipid peroxidation (LPO) levels, and decreased antioxidant levels in DMBA/TPA-treated mice. However, topical application of ZnONPs magnificently reverted the tumor occurrence, histological changes, elevated malanoldehyde and hydrogen peroxide levels; decreased antioxidant levels in DMBA/TPA-treated mice. ZnONPs-PG treatment suppressed the increased levels of inflammatory markers (COX-2, iNOS and NF-κB,) and cell proliferation markers (Cyclin-E1, Cyclin D1, VEGF, TGF-ß1) exposed mice. In addition, ZnONPs-PG treatment decreased the DMBA/TPA-induced anti-apoptotic Bcl-2 protein and increasing the expression of pro-apoptotic markers (Bax and caspase 3) in skin tissues. Thus, ZnONPs-PG may prevent skin carcinogenesis through its potent antioxidant properties and inhibiting NF-κB-mediated inflammatory and proliferation pathways.

Effects of foliar spraying different sizes of zinc fertilizer on the growth and cadmium accumulation in rice.

BACKGROUND: Nanotechnology has been widely applied in agricultural science. During the process of reducing metal toxicity and accumulation in rice, nanomaterials exhibit size effects. However, there is limited knowledge regarding these size effects. We aim to explore the impact of fertilizer with various sizes of ZnO nanoparticles (ZnO-NPs) on rice growth and cadmium (Cd) accumulation and to elucidate the potential mechanism of Cd reduction in rice. Foliar applications of different concentrations (0.5 and 2 mmol L-1) and different sizes (30 and 300 nm ZnO-NPs) of zinc (Zn) fertilizer (Zn(NO3)2) were performed to investigate the effects on rice growth, Cd accumulation and subcellular distribution, and the expression of Zn-Cd transport genes. RESULTS: The results suggested that all the foliar sprayings can significantly reduce the Cd concentrations in rice grains by 41-61% with the highest reduction in the application of ZnO-NPs with large size and low concentration. This is related to the enhancement of Cd fixation in leaf cell walls and downregulation of Cd transport genes (OsZIP7, OsHMA2, OsHMA3) in stem nodes. Foliar ZnO-NPs applications can increase the Zn concentration in grains by 9-21%. Foliar applications of Zn(NO3)2 and small-sized ZnO-NPs promoted plant growth and rice yield, while the application of large-sized ZnO-NPs significantly reduced rice growth and yield. CONCLUSION: The study suggests that the rice yield and Cd reduction are dependent on the size and concentration of foliar spraying and the use of large-sized ZnO-NPs is the most effective strategy when considering both yield and Cd reduction comprehensively. © 2024 Society of Chemical Industry.

Comparative Effect of Antioxidant and Antibacterial Potential of Zinc Oxide Nanoparticles from Aqueous Extract of Nepeta nepetella through Different Precursor Concentrations.

Antibiotic resistance is a global health crisis caused by the overuse and misuse of antibiotics. Accordingly, bacteria have developed mechanisms to resist antibiotics. This crisis endangers public health systems and medical procedures, underscoring the urgent need for novel antimicrobial agents. This study focuses on the green synthesis of ZnO nanoparticles (NPs) using aqueous extracts from Nepeta nepetella subps. amethystine leaves and stems, employing different zinc sulfate concentrations (0.5, 1, and 2 M). NP characterization included transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD), along with Fourier transform infrared spectroscopy (FTIR) analysis. This study aimed to assess the efficacy of ZnO NPs, prepared at varying concentrations of zinc sulfate, for their capacity to inhibit both Gram-positive and Gram-negative bacteria, as well as their antioxidant potential using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method. SEM and TEM results showed predominantly spherical NPs. The smallest size (18.5 ± 1.3 nm for leaves and 18.1 ± 1.3 nm for stems) occurred with the 0.5 M precursor concentration. These NPs also exhibited remarkable antibacterial activity against both Gram-positive and Gram-negative bacteria at 10 µg/mL, as well as the highest antioxidant activity, with an IC50 (the concentration of NPs that scavenge 50% of the initial DPPH radicals) of 62 ± 0.8 (µg/mL) for the leaves and 35 ± 0.6 (µg/mL) for the stems. NPs and precursor concentrations were modeled to assess their impact on bacteria using a 2D polynomial equation. Response surface plots identified optimal concentration conditions for antibacterial effectiveness against each species, promising in combating antibiotic resistance.

Evaluation of Antibacterial Effect of Hybrid Nano-coating of Stainless Steel Orthodontic Brackets on Streptococcus Mutans - An In vitro Study.

Nano-coating of orthodontic brackets with a combination or hybrid of metals and metal oxides may reduce the streptococcus mutans count and incidence of enamel decalcification seen around brackets in patients undergoing fixed orthodontic treatment. In total, 255 orthodontic brackets (3M Unitek, Monrovia, California, USA) were divided into one control group (group I) of 60 and three experimental groups of 65 each (groups II, III, and IV). The experimental group brackets were coated with a combination of silver-zinc oxide, copper oxide -zinc oxide, and silver-copper oxide nanoparticles using physical vapour deposition method. The two nanoparticles used for each group were mixed in the ratio of 1:1 by weight for providing a uniform hybrid coating. Sixty brackets from each group were used for microbiological evaluation of antibacterial activity against Streptococcus mutans in blood agar medium, and the remaining five brackets from each experimental group were used for SEM analysis to check the uniformity of the coating. Nano-coated brackets demonstrated better antibacterial properties than uncoated brackets. Copper oxide-zinc oxide nanoparticles coated brackets demonstrated better antibacterial properties than the silver-zinc oxide and silver- copper oxide coated brackets.

Green Synthesis and Characterization of Zinc Oxide Nanoparticles Using Catharanthus roseus Extract: A Novel Approach.

BACKGROUND: Nanotechnology enables precise manipulation of matter at the molecular level, with nanoparticles offering diverse applications in medicine and beyond. Green synthesis methods, utilizing natural sources like plant extracts, are favored for their eco-friendliness. Zinc oxide (ZnO) nanoparticles are recognized for their ability to combat microbes and reduce inflammation, which holds promise for biomedical applications. Catharanthus roseus, renowned for its medicinal properties, warrants further exploration in oral health management due to its anti-inflammatory and antioxidant attributes. AIM: The current study aimed to synthesize Catharanthus roseus-mediated ZnO nanoparticles and to evaluate their anti-inflammatory and antioxidant activity. MATERIALS AND METHODS: Catharanthus roseus powder (1 g) was dissolved in distilled water (100 ml), heated at 60°C for 15-20 minutes, and filtered to obtain 20 ml extract. ZnO nanoparticles were synthesized by adding 0.594 g ZnO powder to 50 ml water, mixed with plant extract, and stirred for 72 hours, and the resulting solution was centrifuged. Nanoparticles were collected and analyzed for Fourier-transform infrared spectroscopy (FTIR) using Bruker's Alpha II FTIR spectrometer (Bruker, Billerica, Massachusetts, United States), antioxidant, and anti-inflammatory activities. RESULTS: FTIR analysis revealed characteristic peaks indicative of functional groups present in Catharanthus roseus-mediated ZnO nanoparticles, including O-H, N-O, C-O, C=C, and C≡C-H. Anti-inflammatory activity evaluation showed inhibition ranging from 48% to 89%, with the maximum inhibition at 50 µL concentration. Similarly, antioxidant activity ranged from 62% to 88%, with the maximum inhibition also seen at 50 µL concentration. CONCLUSION: Both assays effectively showcased the superior anti-inflammatory and antioxidant activity of the Catharanthus roseus-incorporated ZnO nanoparticles extract compared to the control. This suggests their potential as a viable therapeutic agent for further evaluation.