Visible Light-Activated Room Temperature NO2 Gas Sensing Based on the In2O3@ZnO Heterostructure with a Hollow Microtube Structure.

The persistent challenge of poor recovery characteristics of NO2 sensors operated at room temperature remains significant. However, the development of In2O3-based gas sensing materials provides a promising approach to accelerate response and recovery for sub-ppm of NO2 detection at room temperature. Herein, we propose a simple two-step method to synthesize a one-dimensional (1D) In2O3@ZnO heterostructure material with hollow microtubes, by coupling metal-organic frameworks (MOFs) (MIL-68 (In)) and zinc ions. Meanwhile, the In2O3@ZnO composite-based gas sensor exhibits superior sensitivity performance to NO2 under visible light activation. The response value to 5 ppm of NO2 at room temperature is as high as 1800, which is 35 times higher than that of the pure In2O3-based sensor. Additionally, the gas sensor based on the In2O3@ZnO heterostructure demonstrates a significantly reduced response/recovery time of 30 s/67 s compared to the sensor based on pure In2O3 (74 s/235 s). The outstanding gas sensing properties of the In2O3@ZnO heterostructure-based sensors can be attributed to the enhanced photogenerated charge separation efficiency resulting from the heterostructure effect, and the improved receptor function toward NO2, which can increase the reactive sites and gas adsorption capacity. In summary, this work proposes a low-cost and efficient method to synthesize a 1D heterostructure material with microtube structures, which can serve as a fundamental technique for developing high-performance room-temperature gas sensors.

Poly-vinyl-pyrrolidone capped luminescent zinc oxide nanocomposites as excellent tools for germicidal and photo-catalytic performances.

Alternate antibiotics developed through the involvement of nanomaterials are gaining interest due to their economical and lower toxicity concerns. A newly developed biopolymer-based polyvinylpyrrolidone/zinc oxide (PVP/ZnO) nanocomposite (NCs) was efficiently synthesized by an environment-friendly approach, utilizing onion and garlic peel extract as a bio-surfactant, zinc acetate as the source, PVP as the stabilizing agent, and sodium hydroxide as the precipitant. Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) investigations verified the crystalline properties of ZnO, PVP, and PVP/ZnO-based NCs. The structure of the biopolymer-linked ZnO particles interpolated inside the PVP array was seen to have a layered and flaky structure, as validated by field emission scanning electron microscopy (FE-SEM) analysis, which revealed its occurrence in the nanometer range. The XRD examination verified that the surface topographical image of PVP/ZnO NCs had an average thickness of 21 nm. The PVP/ZnO nanocrystals demonstrated exceptional photocatalytic efficacy, with a breakdown rate of 88% and almost 92% for the methylene blue dye. Therefore, the PVP/ZnO matrix exhibits superior antibacterial activity compared to other extracts, resulting in greater microbial suppression. The results above indicate that the ZnO-intercalated PVP array has a stronger reinforcing effect than other components. Hence, PVP/ZnO nanocrystals exhibit enormous potential as a favorable substance for environmental and biomedical intentions.

Examining the quaternary ammonium chitosan Schiff base-ZnO nanocomposite's potential as protective therapy for rats' cisplatin-induced hepatotoxicity.

BACKGROUND: Despite cisplatin's long history as a cornerstone in cancer therapy, both acquired chemoresistance and significant impacts on healthy tissues limit its use. Hepatotoxicity is one of its side effects. Adjunct therapies have shown promise in not only attenuating liver damage caused by cisplatin but also in enhancing the efficacy of chemotherapy. In this context, a new quaternary ammonium chitosan Schiff base (QACSB) was synthesized and applied as an encapsulating agent for the in-situ synthesis of QACSB-ZnO nanocomposite. MATERIAL AND METHODS: Thirty male albino rats were classified into Group 1 (control) distilled water, Group 2 (Cisplatin-treated) (12 mg/kg, i.p), and Group 3 (QACSB-ZnO NCs/cisplatin-treated) (150 mg/kg/day QACSB-ZnO NCs, i.p) for 14 days + a single dose of cisplatin. Liver functions, tissue TNF-α, MDA, and GSH were measured as well as histopathological and immunohistochemical studies were performed. RESULTS: The QACSB-ZnO NCs significantly restore liver functions, tissue TNF-α, MDA, and GSH levels (p < 0.001). Histopathological examination showed patchy necrosis in the cisplatin-treated group versus other groups. The QACSB-ZnO NCs showed a weak TGF-ß1 (score = 4) and a moderate Bcl-2 immunohistochemistry expression (score = 6) versus the CP group. CONCLUSIONS: QACSB-ZnO NCs have been shown to protect the liver from cisplatin-induced hepatotoxicity.

Duo photoprotective effect via silica-coated zinc oxide nanoparticles and Vitamin C nanovesicles composites.

OBJECTIVE: Zinc Oxide nanoparticles (ZnO NPs) are used widely in nowadays personal care products, especially sunscreens, as a protector against UV irradiation. Yet, they have some reports of potential toxicity. Silica is widely used to cage ZnO NPs to reduce their potential toxicity. Vitamin C derivative, Magnesium Ascorpyl Phosphate (MAP), is a potent antioxidant that can efficiently protect human skin from harmful impacts of UV irradiation and oxidative stress. The combination of silica coated ZnO NPs and MAP nanovesicles could have potential synergistic protective effect against skin photodamage. METHODS: Silica coated ZnO NPs and MAP nanovesicles (ethosomes and niosomes) were synthesized, formulated, and evaluated as topical gels. These gel formulations were evaluated in mice for their photoprotective effect against UV irradiation through histopathology and immuno-histochemistry study. Split-face clinical study was conducted to compare the effect of application of silica coated ZnO NPs either alone or combined with MAP nanovesicles. Their photoprotective action was evaluated, using Antera 3D® camera, for melanin level, roughness index and wrinkles depth. RESULTS: Silica coated ZnO NPs when combined with MAP nanovesicles protected mice skin from UV irradiation and decreased the expression of the proinflammatory cytokines, NF-κB. Clinically, silica coated ZnO NPs, alone or combined with MAP nanovesicles, could have significant effect to decrease melanin level, roughness index and wrinkles depth with higher effect for the combination. CONCLUSION: A composite of silica coated ZnO NPs and MAP nanovesicles could be a promising cosmetic formulation for skin protection against photodamage signs such as hyperpigmentation, roughness, and wrinkles.

Compatibility and performance study of electrohydrodynamic printing using zinc oxide inkjet ink.

The demand for modern electronics and semiconductors has increased throughout the years, which has enabled the innovation and exploration of solution-processed deposition. Solution-based processes have gained a lot of interest due to the low-cost fabrication and the large fabrication areas without the need for high-vacuum equipment. In this study, we utilized the ZnO ink for inkjet printer ink to fabricate a thin film via Electrohydrodynamic printing. Three different ink solutions were prepared for experimentation. The EHD printing technique demonstrated the ink's compatibility with and without the modifications. The outcomes of the EHD printed materials were comparable with the spin-coated thin films. The EHD-printed films demonstrated better results in comparison to spin-coated films. Ra and Rq of the EHD film measured at 3.651 nm and 4.973 nm, respectively. It improved the absorbance up to two-fold at 360 nm wavelength and electrical conductivity up to 40% compared to the spin-coated films. Furthermore, the optimization of the printing parameters can lead to the improved morphology and thickness of the EHD thin films.

Enhancing zinc biofortification and mitigating cadmium toxicity in soil-earthworm-spinach systems using different zinc sources.

Cadmium (Cd) pollution poses significant threats to soil organisms and human health by contaminating the food chain. This study aimed to assess the impact of various concentrations (50, 250, and 500 mg·kg-1) of zinc oxide nanoparticles (ZnO NPs), bulk ZnO, and ZnSO4 on morphological changes and toxic effects of Cd in the presence of earthworms and spinach. The results showed that Zn application markedly improved spinach growth parameters (such as fresh weight, plant height, root length, and root-specific surface area) and root morphology while significantly reducing Cd concentration and Cd bioconcentration factors (BCF-Cd) in spinach and earthworms, with ZnO NPs exhibiting the most pronounced effects. Earthworm, spinach root, and shoot Cd concentration decreased by 82.3 %, 77.0 %, and 75.6 %, respectively, compared to CK. Sequential-step extraction (BCR) analysis revealed a shift in soil Cd from stable to available forms, consistent with the available Cd (DTPA-Cd) results. All Zn treatments significantly reduced Cd accumulation, alleviated Cd-induced stress, and promoted spinach growth, with ZnO NPs demonstrating the highest Cd reduction and Zn bioaugmentation efficiencies compared to bulk ZnO and ZnSO4 at equivalent concentrations. Therefore, ZnO NPs offer a safer and more effective option for agricultural production and soil heavy metal pollution management than other Zn fertilizers.

Enhanced third-order nonlinear optical properties of ZnO@C-N composite microspheres.

We report the third-order nonlinear optical (NLO) properties of ZnO@C-N composite microspheres and pure ZnO which have been investigated with the Z-scan technique under continuous wave laser. ZnO@C-N composite microspheres have been hydrothermally synthesized at two different precursor concentrations to have structures at different impurity levels. Moreover, pure ZnO is prepared under the annealing process. The nonlinear optical absorption of samples was measured by using the open-aperture Z-scan technique and was evaluated relating to the two-photon absorption (TPA) mechanism. Moreover, both ZnO@C-N and ZnO microstructures exhibited a negative nonlinear refractive index (NLR) referring to the self-defocusing effect. The order of the (NLR) value, is about 10-10(cm2/W) and, the NLA coefficients of specimens are in the order of 10-5(cm/W). The NLA coefficient has a similar behavior as the NLR versus increasing incident intensity of the laser. The results show that the nonlinearity response of ZnO@C-N composites is higher than the pure ZnO and ZnO@C-N at higher precursor concentrations exhibits the maximum amount of NLA and NLR coefficients compared to other samples. This observation which is attributed to the change in optical and structural properties of material due to impurity presence, underscores the presence of impurity for engineering materials to improve the nonlinearity properties.

Transiently controlled emission from ZnO surface.

We report on a photon (~3.08 eV equivalent to 402 nm) controlled optical emission from ZnO (10-10). Under below band gap excitation (~2.33 eV equivalent to ~532 nm), significant photoluminescence (PL) overlapped with Raman response is observed. The broad PL consists of three bands (629 (A), 690 (B), and 751 (C) nm) attributed to the defects arising due to excess zinc and charged oxygen vacancy. By employing a second excitation source at 402 nm, we demonstrate about 50% reduction in the overall PL. We utilize the doubly positive oxygen vacancy state to control the PL emission while transiently reducing its density. .

Antibacterial Size Effect of ZnO Nanoparticles and Their Role as Additives in Emulsion Waterborne Paint.

Nosocomial infections, a prevalent issue in intensive care units due to antibiotic overuse, could potentially be addressed by metal oxide nanoparticles (NPs). However, there is still no comprehensive understanding of the impact of NPs' size on their antibacterial efficacy. Therefore, this study provides a novel investigation into the impact of ZnO NPs' size on bacterial growth kinetics. NPs were synthesized using a sol-gel process with monoethanolamine (MEA) and water. X-ray diffraction (XRD), transmission electron microscopy (TEM), and Raman spectroscopy confirmed their crystallization and size variations. ZnO NPs of 22, 35, and 66 nm were tested against the most common nosocomial bacteria: Escherichia coli, Pseudomonas aeruginosa (Gram-negative), and Staphylococcus aureus (Gram-positive). Evaluation of minimum inhibitory and bactericidal concentrations (MIC and MBC) revealed superior antibacterial activity in small NPs. Bacterial growth kinetics were monitored using optical absorbance, showing a reduced specific growth rate, a prolonged latency period, and an increased inhibition percentage with small NPs, indicating a slowdown in bacterial growth. Pseudomonas aeruginosa showed the lowest sensitivity to ZnO NPs, attributed to its resistance to environmental stress. Moreover, the antibacterial efficacy of paint containing 1 wt% of 22 nm ZnO NPs was evaluated, and showed activity against E. coli and S. aureus.

Tunable Hydrogen-Related Defects in ZnO Nanowires Using Oxygen Plasma Treatment by Ion Energy Adjustment.

The chemical bath deposition (CBD) process enables the deposition of ZnO nanowires (NWs) on various substrates with customizable morphology. However, the hydrogen-rich CBD environment introduces numerous hydrogen-related defects, unintentionally doping the ZnO NWs and increasing their electrical conductivity. The oxygen-based plasma treatment can modify the nature and amount of these defects, potentially tailoring the ZnO NW properties for specific applications. This study examines the impact of the average ion energy on the formation of oxygen vacancies (VO) and hydrogen-related defects in ZnO NWs exposed to low-pressure oxygen plasma. Using X-ray photoelectron spectroscopy (XPS), 5 K cathodoluminescence (5K CL), and Raman spectroscopy, a comprehensive understanding of the effect of the oxygen ion energy on the formation of defects and defect complexes was established. A series of associative and dissociative reactions indicated that controlling plasma process parameters, particularly ion energy, is crucial. The XPS data suggested that increasing the ion energy could enhance Fermi level pinning by increasing the amount of VO and favoring the hydroxyl group adsorption, expanding the depletion region of charge carriers. The 5K CL and Raman spectroscopy further demonstrated the potential to adjust the ZnO NW physical properties by varying the oxygen ion energy, affecting various donor- and acceptor-type defect complexes. This study highlights the ability to tune the ZnO NW properties at low temperature by modifying plasma process parameters, offering new possibilities for a wide variety of nanoscale engineering devices fabricated on flexible and/or transparent substrates.

In-Situ Hydrothermal Fabrication of ZnO-Loaded GAC Nanocomposite for Efficient Rhodamine B Dye Removal via Synergistic Photocatalytic and Adsorptive Performance.

In this work, zinc oxide (ZnO)/granular activated carbon (GAC) composites at different ZnO concentrations (0.25M-ZnO@GAC, 0.5M-ZnO@GAC, and 0.75M-ZnO@GAC) were prepared by an in-situ hydrothermal method and demonstrated synergistic photocatalytic degradation and adsorption of rhodamine B (RhB). The thermal stability, morphological structure, elemental composition, crystallographic structure, and textural properties of developed catalysts were characterized by thermal gravimetric analysis (TGA/DTG), scanning electron microscopy equipped with energy dispersive-x-ray (SEM-EDS), X-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) analysis. The successful loading of ZnO onto GAC was confirmed by SEM-EDS and XRD analysis. The BET surface areas of GAC, 0.25M-ZnO@GAC, 0.5M-ZnO@GAC, and 0.75M-ZnO@GAC were 474 m2/g, 450 m2/g, 453 m2/g, and 421 m2/g, respectively. The decrease in GAC could be attributed to the successful loading of ZnO on the GAC surface. Notably, 0.5M-ZnO@GAC exhibited the best photocatalytic degradation efficiency of 82% and 97% under UV-A and UV-C light over 120 min, attributed to improved crystallinity and visible light absorption. The photocatalytic degradation parameters revealed that lowering the RhB concentration and raising the catalyst dosage and pH beyond the point of zero charge (PZC) would favor the RhB degradation. Photocatalytic reusability was demonstrated over five cycles. Scavenger tests revealed that the hydroxyl radicals (•OH), superoxide radicals (O2-•), and photoinduced hole (h+) radicals play a major role during the RhB degradation process. Based on the TOC results, the RhB mineralization efficiency of 79.1% was achieved by 0.5M-ZnO@GAC. Additionally, GAC exhibited a strong adsorptive performance towards RhB, with adsorption capacity and the RhB removal of 487.1 mg/g and 99.5% achieved within 90 min of equilibrium time. The adsorption characteristics were best described by pseudo-second-order kinetics, suggesting chemical adsorption. This research offers a new strategy for the development of effective photocatalyst materials with potential for wider wastewater treatment applications.

Carica Papaya leaf-infused metal oxide nanocomposite: a green approach towards water treatment and antibacterial applications.

This study successfully synthesized ZnO-CuO nanocomposite using the hydrothermal method with Carica papaya leaf extract. The incorporation of the leaf extract significantly enhanced the nanocomposite properties, a novel approach in scientific research. Characterization techniques, including X-ray diffraction, Fourier Transmission Infrared spectroscopy, and Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis, confirmed a cubic crystal structure with an average size of 22.37 nm. The Fourier Transmission Infrared spectrum revealed distinctive vibrations at 627, 661, and 751 cm-1 corresponding to ZnO-CuO nanocomposite corresponding to stretching and vibration modes. SEM images confirmed a cubic-like and irregular structure. The nanocomposite exhibited outstanding photocatalytic activity, degrading methylene blue dye by 96.73% within 120 min under visible light. Additionally, they showed significant antimicrobial activity, inhibiting Staphylococcus aureus (20 mm) and Klebsiella pneumonia (17 mm). The results highlight the efficiency of Carica papaya leaf-derived ZnO-CuO nanocomposite for environmental and health challenges.

Removal of bisphenol a micropollutants released from plastic waste using Pt-ZnO photocatalyst.

Plastic pollution is becoming increasingly severe and is attracting global attention. One of its consequences is the recent discovery of micropollutant discharge into water, with Bisphenol A (BA-MP) being a typical example. This study utilizes an advanced oxidation process based on Pt-doped ZnO photocatalyst to remove BA-MP. Health concerns related to the release of BA-MP from plastic waste are discussed. Besides, the results of the photodegradation experiment show that the Pt-ZnO photocatalyst can remove 94.1% of BA-MP within 60 min when exposed to solar light. Moreover, after five reuse cycles, Pt-ZnO retains a high BA-MP removal efficiency of 71.2%, and its structure remains largely unchanged compared to the original material. The removal efficiency of BA-MP leaching from plastic waste was measured at 98.8%, confirming the suitability of Pt-ZnO for the treatment of micropollutants. Furthermore, this study also highlights the prospects and challenges of using Pt-ZnO for the treatment of micropollutants discharged from plastic waste.

Designing copper-doped zinc oxide nanoparticle by tobacco stem extract-mediated green synthesis for solar cell efficiency and photocatalytic degradation of methylene blue.

This study presents the green synthesis of copper-doped zinc oxide (Cu-doped ZnO) nanoparticles using tobacco stem (TS) extract. The environmentally friendly synthesis method ensures distinct features, high efficiency, and applicability in various fields, particularly in solar cell technology and photocatalytic applications. ZnO nanostructures are investigated due to their unique properties, cost-effectiveness, and broad range of applications. The nanoparticles are synthesized with varying Cu concentrations, and their structural, morphological, and compositional characteristics are thoroughly analyzed. The Cu-doped ZnO nanoparticles exhibit improved properties, such as increased surface area and reduced particle size, attributed to the incorporation of Cu dopants. The green synthesis approach using TS extract serves as a stabilizing agent and avoids the toxicity associated with chemical methods. Characterization techniques including SEM, TEM, EDX, FTIR, and XRD confirm the successful synthesis of the nanoparticles. Photocatalytic degradation studies reveal that the 5% Cu-doped ZnO exhibits the highest photocatalytic activity against methylene blue, attributed to synergistic effects between Cu and ZnO, including oxygen vacancy and electron-hole pair recombination rate suppression. The photocatalytic mechanism involves the generation of superoxide and hydroxyl radicals, leading to methylene blue degradation. Furthermore, the Cu-doped ZnO nanoparticles demonstrate promising photovoltaic performance, with the optimal efficiency observed at a 5% Cu concentration. The study suggests that Cu-doped ZnO has the potential to enhance solar cell efficiency and could serve as an alternative material in solar cell applications. Future research should focus on refining Cu-doped ZnO for further improvements in solar energy conversion efficiency.

The successful synthesis of Cu-doped ZnO nanoparticles from tobacco stem extract suggests an environmentally friendly approach. The photocatalytic degradation studies demonstrate the superior activity of 5% Cu-doped ZnO against methylene blue, attributed to synergistic effects between Cu and ZnO. Cu-doped ZnO has the potential to significantly enhance solar cell efficiency. The demonstrated photocatalytic and photovoltaic activities of Cu-doped ZnO open avenues for further research in optimizing their performance for practical applications in solar energy technologies and sustainable energy production.

Exploring the multi-faceted potential: Synthesized ZnO nanostructure - Characterization, photocatalysis, and crucial biomedical applications.

This research describes the methodology for synthesizing zinc oxide nanoparticles (ZnO-NPs). It demonstrates a unique, cost-effective, and non-toxic chemical technique for producing ZnO-NPs using the precipitation method with NaOH as reducing and capping agents. The formed nanoparticles have been characterized and analyzed using numerous techniques such as; Fluorescence emission spectroscopy (FL), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray Spectroscopy (EDX), ultraviolet-visible optical absorption (UV-Vis), Fourier transform infrared spectroscopy (FTIR), and Thermal gravimetric analysis (TGA). Also, the analytical technique X-ray diffraction studies has been used which showed that the ZnO-NPs had a Wurtzite hexagonal crystal structure with an average crystallite size of 34.27 nm. The form and the size of the synthesized ZnO-NPs have been seen in SEM and TEM photographs. Using J-image, particle size has been obtained at 13.33 nm, and the grain boundaries were all approximately spherical. Peaks in the FT-IR spectrum of the NPs indicate the presence of carboxylate (COO) and hydroxyl (O-H) functional groups. According to these findings, Zn interstitial defects are responsible for the 380 nm emission peak. Since EDX could not identify any impurities below the detection threshold, we may be sure that Zn and O are the principal components of the synthesized sample. ZnO-NPs cause an absorption band at 350.34 nm in the UV-Vis spectrum and a band gap of 3.24 eV. The catalytic activity of the synthesized ZnO nanoparticles (NPs) was evaluated by investigating their effectiveness in degrading crystal violet (CV) and methylene blue (MB) dyes, along with assessing the degradation rates. The results demonstrated a high degradation efficiency, with ZnO NPs achieving approximately 96.72 % degradation for CV and 97.169 % for MB dyes, underscoring their remarkable efficacy in the degradation process. As for antimicrobial activity assessment, the results revealed that the ZnO-NPs had negligible impact on Gram-negative bacteria, whereas they exhibited a discernible effect on Gram-positive bacteria. Additionally, it showed anti-cancer potential against colon (SW480), breast (MDA-231), and cervix (HELA) lines cells as seen by (MTT) assay. Hence, due to its simplified processes and cheaper chemicals, our synthesis technique may use in industrial settings for various applications.

Real-Time Ultraviolet Monitoring System with Low-Temperature Solution-Processed High-Transparent p-n Junction Photodiode with a Fast Responsive and High Rectification Ratio.

We introduce an enhanced performance organic-inorganic hybrid p-n junction photodiode, utilizing poly[bis(4-phenyl) (2,4,6-trimethylphenyl)amine] (PTAA) and ZnO, fabricated through a solution-based process at a low temperature under 100 °C. Improved interfacial electronic structure, characterized by shallower Gaussian standard deviation of the density-of-state distribution and a larger interface dipole, has resulted in a remarkable fold increase of ∼102 in signal-to-noise ratio for the device. This photodiode exhibits a high specific detectivity (2.32 × 1011 Jones, cm×Hz×W-1) and exceptional rectification ratio (5.47 × 104 at ±1 V). The primary light response, concentrated in the optimal thickness of the PTAA layer, contributes to response over the entire UVA region and rapid response speed, with rise and fall times of 0.24 and 0.64 ms, respectively. Furthermore, this work demonstrates immense potential of our device for health monitoring applications by enabling real-time and continuous measurements of UV intensity.

Zno nanoparticles: improving photosynthesis, shoot development, and phyllosphere microbiome composition in tea plants.

BACKGROUND: Nanotechnology holds revolutionary potential in the field of agriculture, with zinc oxide nanoparticles (ZnO NPs) demonstrating advantages in promoting crop growth. Enhanced photosynthetic efficiency is closely linked to improved vigor and superior quality in tea plants, complemented by the beneficial role of phyllosphere microorganisms in maintaining plant health. However, the effects of ZnO NPs on the photosynthesis of tea plants, the sprouting of new shoots, and the community of phyllosphere microorganisms have not been fully investigated. RESULTS: This study investigated the photosynthetic physiological parameters of tea plants under the influence of ZnO NPs, the content of key photosynthetic enzymes such as RubisCO, chlorophyll content, chlorophyll fluorescence parameters, transcriptomic and extensive targeted metabolomic profiles of leaves and new shoots, mineral element composition in these tissues, and the epiphytic and endophytic microbial communities within the phyllosphere. The results indicated that ZnO NPs could enhance the photosynthesis of tea plants, upregulate the expression of some genes related to photosynthesis, increase the accumulation of photosynthetic products, promote the development of new shoots, and alter the content of various mineral elements in the leaves and new shoots of tea plants. Furthermore, the application of ZnO NPs was observed to favorably influence the microbial community structure within the phyllosphere of tea plants. This shift in microbial community dynamics suggests a potential for ZnO NPs to contribute to plant health and productivity by modulating the phyllosphere microbiome. CONCLUSION: This study demonstrates that ZnO NPs have a positive impact on the photosynthesis of tea plants, the sprouting of new shoots, and the community of phyllosphere microorganisms, which can improve the growth condition of tea plants. These findings provide new scientific evidence for the application of ZnO NPs in sustainable agricultural development and contribute to advancing research in nanobiotechnology aimed at enhancing crop yield and quality.

Neuroprotective Effects of Zinc Oxide Nanoparticles in a Rotenone-Induced Mouse Model of Parkinson's Disease.

Goals of the investigation: This work aimed to evaluate the neuroprotective effects of zinc oxide (ZnO) nanoparticles in an experimental mouse model of rotenone-induced PD and investigate the therapeutic effects of ZnO, cobalt ferrite nanoparticles, and their combination. Methods: The levels of dopamine, norepinephrine, epinephrine, and serotonin were assessed using ELISA in the control and experimental model of PD mice. The dopa-decarboxylase expression level was assayed by real-time PCR. The expression level of tyrosine hydroxylase (TH) was assessed by western blot analysis. Results: Our data showed that levels of dopamine decreased in PD mice compared to normal. ZnO NP increased dopamine levels in normal and PD mice (37.5% and 29.5%; respectively, compared to untreated mice). However, ZnO NP did not cause any change in norepinephrine and epinephrine levels either in normal or in PD mice. Levels of serotonin decreased by 64.0%, and 51.1% in PD mice treated with cobalt ferrite and dual ZnO- cobalt ferrite NPs; respectively, when compared to PD untreated mice. The mRNA levels of dopa-decarboxylase increased in both normal and PD mice treated with ZnO NP. Its level decreased when using cobalt ferrite NP and the dual ZnO-cobalt ferrite NP when compared to untreated PD mice. A significant decrease in TH expression by 0.25, 0.68, and 0.62 folds was observed in normal mice treated with ZnO, cobalt ferrite, and the dual ZnO-cobalt ferrite NP as compared to normal untreated mice. In PD mice, ZnO administration caused a non-significant 0.15-fold decrease in TH levels while both cobalt ferrite and the dual ZnO-cobalt ferrite NP administration caused a significant 0.3 and 0.4-fold decrease respectively when compared to untreated PD mice. Principal conclusion: This study reveals that ZnO NPs may be utilized as a potential intervention to elevate dopamine levels to aid in PD treatment.

Fabrication of alcohol sensor using undoped and Al doped ZnO nanostructure film with polymer electrolyte gating.

We report the fabrication of two terminal and three terminal gas sensor using Al-doped ZnO nanostructured-films and polymer electrolyte gate dielectric on glass substrate using vacuum free chemical method. The Al doped ZnO films are characterized by UV-vis Spectrometer, SEM, EDX and XRD. The characterization results have revealed the polycrystalline structure of both undoped and doped ZnO; with loosely packed, porous, and spherical granny nanostructure with mean grain size 20-10 nm and bandgap of the films is within the range of 3.12-3.16 eV. The conductivity of the ZnO film is tuned by Al concentration and the maximum value of conductivity was observed in 3 % Al doped ZnO films. Similarly, the best performance index of TFT such as current ON/OFF ratio, high transconductance and low threshold voltage was observed in 3 % Al doping concentration. The ordinary (two-terminal) sensor and three-terminal (FET) sensors' responses towards three different concentrations 50, 250, 500 ppm of ethanol and methanol vapors have been studied. The sensitivity of the film is modulated by Al concentration and higher value of sensitivity was achieved at 3 % Al doped ZnO films. The use of polymer electrolyte enhanced the sensitivity of the device which is more effective in methanol vapor. The Response-Recovery time of the sensor is significantly improved in three terminal devices than the two terminal devices.

Ca-doped ZnO nanoparticles for MB dye degradation and adsorptive removal of tinidazole.

Industrial dye degradation involves several processes by which dyes are broken down, ideally into innocuous products. Methylene blue (MB) is one of the most commonly employed dyes in the textile industry and is released into water in routine industry processes. These discharges lead to creating a nocuous nature for humans and animals. Drugs are also discharged into water bodies from various pharmaceutical industries. In these two contexts, in the present work, the green synthesis of calcium-doped zinc oxide nanoparticles (Ca-doped ZnO NPs) is achieved using the aqueous peel extract of Citrus limetta by the solution combustion technique. The structural, morphological, and optical properties of the synthesized Ca-doped ZnO NPs are investigated using XRD, FTIR, SEM, EDX, and UV-visible spectroscopy. The prepared NPs were subjected to photocatalytic degradation of MB dye under visible-light illumination, which shows ~ 95% dye degradation. The synthesized Ca-doped ZnO NPs were also employed to adsorb tinidazole (TDZ), a nitroimidazole antibiotic, from water samples. An excellent adsorptive capacity of the NPs was observed for selectively adsorbing the TDZ ~ 96.2%. The drug TDZ was found to have pseudo-second-order kinetics. The catalyst recycling proved its repeatability; removal of the dye reached up to 92% after three successive usages. Therefore, using waste Citrus limetta peel extract, the multifunctional Ca-doped ZnO NPs were synthesized, which maintained effective adsorption potential and photocatalytic abilities and could be used as an effective material for environmental remediation.