Spherical ZnO NPs Research Articles

Exploring the physicochemical properties and antifungal activity of zinc oxide nanoparticles

ABSTRACT In this study, zinc oxide nanoparticles were synthesized using the chemical precipitation method with zinc acetate dihydrate and sodium hydroxide as precursors. UV-Vis spectroscopy confirmed the formation of ZnONPs, showing a characteristic absorption peak at around 360–370 nm, corresponding to a band gap energy of approximately 3.2 eV. XRD analysis indicated the crystalline nature of ZnONPs with a hexagonal wurtzite structure. FTIR and EDS analyses confirmed the presence of ZnONPs in the component. TEM revealed nearly spherical ZnONPs with average particle sizes of 26.1 nm for bare ZnONPs and 24.6 nm for PVP-capped ZnONPs. BET measurements showed a higher specific surface area for PVP-capped ZnONPs. The antifungal efficacy of ZnONPs was tested against Phytophthora capsici at concentrations ranging from 20 to 100 ppm. Results demonstrated significant inhibition of fungal growth, especially with PVP-capped ZnONPs, with complete inhibition at concentrations ≥60 ppm after 12 to 48 hours of incubation.

Calotropis Gigantea Latex-Derived Zinc Oxide Nanoparticles: Biosynthesis, Characterization, and Biofunctional Applications

Latex of C. gigantea was used to synthesize zinc oxide nanoparticles (ZnO NPs) by the green chemistry approach. The crystalline size, shape, and purity of as-synthesized ZnO NPs were characterized through scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction analysis, and Fourier-transform infrared spectroscopy techniques. Crystalline, spherical ZnO NPs with an average size of 21.8 nm were formed. In addition, the biological properties of the ZnO NPs, such as antioxidant and antibacterial activity, were evaluated by 2,2-diphenyl-1-picrylhydrazyl assay and the agar well-diffusion method. The highest free radical scavenging activities of 83.11 ± 1.89 % were observed at a concentration of 350 μg/mL of C. gigantea latex-mediated ZnO NPs. The latex in the C. gigantea latex-mediated ZnO NPs inhibited the growth of pathogenic bacteria. The maximum zone of inhibition was found in P. aeruginosa and S. aureus. C. gigantea latex-mediated ZnO NPs have significant biocompatibility and broad-spectrum antibacterial properties against wound-causing bacteria and, therefore, can be suggested for use in the formulation of novel creams or gels for healing applications.

MnCo3O4–ZnO heterojunctions for extremely effective photoreduction of Cr6+ ions in aqueous solution utilizing visible illumination

The utilization of the manufactured MnCo3O4–ZnO heterojunctions for the accelerated conversion of Cr6+ ions to Cr3+ via photoreduction under visible illumination is reported in this work. Sol-gel approach was applied to generate mesoporous ZnO with the aid of a surfactant. MnCo3O4 NPs were incorporated into the manufactured ZnO with the percentages of 1, 2, 3, and 4 wt%. The analyses performed to identify the phase composition and microstructure of the manufactured materials (XRD, XPS and TEM) affirmed the creation of greatly distributed MnCo3O4 NPs over spherical ZnO NPs with particle diameters of 10.2 and 40.2 nm, respectively. The photocatalytic performance of the manufactured materials was compared to that of P25. Bandgap energy of the produced MnCo3O4–ZnO heterojunction with 3 wt% MnCo3O4 was lower than the value of pure ZnO, which cooperated significantly with the absorption advancement in the visible region. If the amount of generated MnCo3O4–ZnO photocatalyst was maintained at 2.4 gL-1, the Cr6+ photocatalytic reduction progressed satisfactorily in 45 min at a rate of 286.9 μmol min-1. Subsequent to five trials of the Cr6+ photoreduction, optimized photocatalyst demonstrated excellent recyclability. Photocurrent and photoluminescence experiments showed that the increased photocatalytic reduction rate could be attributable to excellent interfacial charge separation among the photo-created charges inside the produced heterojunction. The finding showed the produced nanocomposite as an impressive photocatalyst for heavy metal ions elimination employing visible illumination.

Anti-cancer effects of biosynthesized zinc oxide nanoparticles using Artemisia scoparia in Huh-7 liver cancer cells

This study is aimed to synthesize zinc oxide nanoparticles (ZnO NPs) by Artemisia scoparia extract and explore their cytotoxic behavior against Huh-7 liver cancer cells. The green-synthesized ZnO NPs were investigated using UV–Vis, FT-IR, XRD, TEM, FESEM, EDX, DLS, and Zeta potential. The anti-cancer activity of ZnO NPs and plant extract against cancer cells was evaluated by MTT assay and flow cytometry. The expression of apoptotic genes was assessed by qPCR. The average size of the ZnO NPs was 9.00 ± 4.00 nm. The A. scoparia extract and spherical ZnO NPs both inhibited cell growth and induced apoptosis in Huh-7 cancer cells in a time- and dose-dependent manner. The IC50 values of ZnO NPs and extract were 10.26 and 310.24 µg/mL, respectively. The ZnO NPs also upregulated pro-apoptotic genes while downregulating anti-apoptotic genes. Considering the anti-cancer features of the ZnO NPs, it seems that the green-synthesized ZnO NPs have strong anti-cancer potential.

Synthesis and growth of spherical ZnO nanoparticles using different amount of plant extract

The use of plant extracts has become an interesting ecofriendly method to synthesize and stabilize the different structures nanoparticles (NPs). This work investigated the effect of plant extract as a reducing and stabilizing agent on the growth and morphology of ZnO nanoparticles (ZnO-NPs). Green synthesis and growth of spherical ZnONPs was carried out by co-precipitation method using a Zinc acetate salt and various amounts of Azadirachta indica seed husk extract (20 ml and 40 ml). The synthesized ZnO-NPs were characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM-EDX), and transmission electron microscopy (TEM). The FTIR analyses revealed the presence of Phenolic alcohol, amines and carboxylic acid groups and ZnO in synthesized NPs with more intense peaks at higher amount (40 ml) of A. indica extract. Also, structural morphology analyses using SEM revealed uniform spherical shaped particles with diameter from 25 to 60 nm (20 ml of extract) and 19 to 35 nm (40 ml of extract) for ZnO-NPs. The EDX spectral revealed that the required phase of Zn and O was present 69.54% (Zn) and 30.46% (O) at 20 ml of extract, also 73.71% (Zn), 26.26% (O) at 40 ml of extract respectively and confirmed high purity for the synthesized ZnO NPs. TEM revealed spherical shaped NPs with diameter ranging from 28 to 52 nm (20 ml of extract) and 8.2 to 11.9 nm (40 ml of extract) respectively, with a trend reduction in particle size of NPs at higher amount of A. indica seed extract (40 ml) and growth of more uniform particles with no agglomeration. The study showed successful growth of spherical ZnO-NPs with required properties at a higher amount of extract.

Eco-friendly Mycogenic Synthesis of ZnO and CuO Nanoparticles for In Vitro Antibacterial, Antibiofilm, and Antifungal Applications.

Mycogenic synthesis of medically applied zinc oxide (ZnO) and copper oxide (CuO) nanoparticles (NPs) were exploited using Penicillium chrysogenum. The biogenesis and capping processes of the produced nano-metals were conducted by functional fungal extracellular enzymes and proteins. The obtained ZnO-NPs and CuO-NPs were characterized. Also, the antibacterial activity and minimum inhibitory concentration (MIC) values of ZnO-NPs and CuO-NPs were determined. Also, antibiofilm and antifungal activities were investigated. Results have demonstrated the ability of the bio-secreted proteins to cape and reduce ZnO and CuO to hexagonal and spherical ZnO-NPs and CuO-NPs with particle size at 9.0-35.0nm and 10.5-59.7nm, respectively. Both ZnO-NPs and CuO-NPs showed high antimicrobial activities not only against Gram-positive and Gram-negative bacteria but also against some phytopathogenic fungal strains. Besides this, those NPs showed varied antibiofilm effects against different microorganisms. Quantitative and qualitative analyses indicated that CuO-NPs had an effective antibiofilm activity against Staphylococcus aureus and therefore can be applied in diverse medical devices. Thus, the mycogenic green synthesized ZnO-NPs and CuO-NPs have the potential as smart nano-materials to be used in the medical field to limit the spread of some pathogenic microbes.

Radiosensitization effect of ZnO nanoparticles in lung cancer cells at clinically relevant megavoltage energy

Introduction: Radiation therapy is one of the major modalities that have long been used in cancer treatment. Radiotherapy is often accompanied by early and late toxicity and side effects and narrow therapeutic window. Similarity in radiation absorption properties of tumors and neighboring healthy tissues is often the reason for low specificity of radiation therapy. Development of nanomaterials for localized energy deposition under irradiation can increases radiation absorption by cancer tissue, expanding the therapeutic window and, thus, increasing specificity and efficacy of the treatment. ZnO nanoparticle is a wide band gap semiconductor with photo-oxidizing capacity under uv radiation. Recent studies have investigated photo-oxidizing under kilovoltage x-ray energy named as radiosensitization. The purpose of this study was to assess ZnO radiosensitization at clinically relevant MV X-ray energy. Materials and Methods: ZnO nanoparticles with mean size of 10 nm were synthetized by a chemical precipitation method. The size, morphology and crystalline structure of the nanoparticles were characterized using transmission electron microscopy (TEM) and X-ray diffraction (XRD), respectively. The cytotoxicity of ZnO nps was evaluated on SKLC-6 lung cancer cell line by cell proliferation assay. The effect of ZnO nps on cell radiosensitivity under 6MV energy x-ray irradiation was evaluated using colonogenic assay. Mode of cell death was evaluated by flow cytometry. Results: TEM images showed spherical ZnO NPs with narrow size distributions were synthesized. XRD pattern of purely synthesized NPs exhibited seven reflection peaks that can be indexed to the ZnO wurtzite structure. ZnO NPs were cytotoxic to the SKLC-6 cells in a dose-dependent manner as cell viability was decrease with the increase concentrations of ZnO nps. When comparing the radiation effects between the nanoparticle-containing and nanoparticle-free samples, the calculated radiation enhancement ratio of about 1.35-fold was achieved. FLow cytometry analysis confirmed that ZnO NPs, irradiation and combination of two induce apoptosis in SKLC-6 cells. Conclusion: The potential of the ZnO nanoparticles for radiosensitization at MV energy was demonstrated in human lung cancer cell line (SKLC-6). Nanoparticle-mediated Enhancement Ratio was 1.35. Radiosensitizing effect can be attributed to X-ray-induced radiocatalysis by the nanoparticles at MV energy. Further development of ZnO nps might provide a new useful tool for research and clinical therapy in the field of oncology.

The impact of morphology and size of zinc oxide nanoparticles on its toxicity to the freshwater microalga, Raphidocelis subcapitata.

Microalgae are key test organisms to assess the effects of chemicals on aquatic ecosystems. Zinc oxide nanoparticles (ZnO NPs) as a widely used metal oxide is considered a potential threat to these primary producers at the base of the food chain. This study investigates the toxicity of ZnO NPs, bulk ZnO, and Zn2+ to the representative of freshwater microalgae, Raphidocelis subcapitata. To examine the effect of shape and size of nanoparticles, two types of spherical ZnO NPs with different sizes (20 and 40nm) and two types of rod-shaped ZnO NPs with different lengths (100 and 500nm) were synthesized. Microalgal cells were exposed to eight concentrations of each ZnO NP type from 0.01 to 0.7mg/L for 96h. The results showed that 0.7mg/L of ZnO NP could completely inhibit algal growth. Size did not interfere with toxicity in spherical ZnO NPs, but the toxicity decreased by increasing the size of rod-shaped ZnO NPs. Spherical ZnO NPs acted more destructive to microalgal cells than nanorod shape. The addition of 0.7mg/L of ZnO nanorods to samples caused 30% cell death, while 50% cell death was observed by adding the same concentration of nanospherical ZnO. Nano ZnO revealed to be more toxic than bulk ZnO and Zn2+. The Zn2+ released from dissolution of ZnO NPs was one of the sources of toxicity, but the ZnO nanostructures were also an important factor in the toxicity.

Cytotoxicity, antibacterial and antifungal activities of ZnO nanoparticles prepared by the Artocarpus gomezianus fruit mediated facile green combustion method

Abstract Spherical nanoparticles of zinc oxide (ZnO NPs) were synthesized by an eco-friendly green combustion method using citrate containing Artocarpus gomezianus fruit extract as a fuel. The morphology, compositions and structure of the product were characterized by Powder X-ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Fourier Transform Infra-red (FTIR), UV–Visible (UV–Vis) and Raman Spectroscopy. Highly uniform spherical zinc oxide NPs were subjected to cytotoxicity, antifungal and antibacterial activities. PXRD patterns show that the product formed belongs to a hexagonal wurtzite system. SEM micrographs reveal that the particles are agglomerated. The TEM images demonstrate that the particles are highly uniform spherical in shape and loosely agglomerated. Scherrer's method and W H plots were used to calculate the average crystallite sizes, yielding 39, 35, 31 and 40, 37, 32 nm for ZnO NPs prepared with 5, 10 and 15 mL of 10% Artocarpus gomezianus fruit extract, respectively. These results were confirmed by the TEM observations. Breast cancer cell lines (MCF-7) were subjected to in vitro anticancer activity. MTT assay revealed a good anticancer activity of ZnO NPs against MCF-7. Zone of the inhibition method shows that the spherical ZnO NPs also exhibit significant antibacterial activity against staphylococcus aureus and antifungal activity against Aspergillus niger. The synthesized ZnO NPs can find plausible biological applications.

Biosynthesis of ZnO nanoparticles using barberry (Berberis vulgaris) extract and assessment of their physico-chemical properties and antibacterial activities

AbstractZinc oxide nanoparticles (ZnO NPs) were synthesized using barberry (Berberis vulgaris) extract via heating method. The effects of the amount of barberry extract (15–35 ml) and the reaction time (30–90 min) on the antibacterial (clear zone diameter, mm) and antioxidant (%) activities of the synthesized ZnO NPs were investigated by response surface methodology. Main reducing and stabilizing compounds of barberry extract were identified by gas chromatography and Fourier transform infrared spectroscopy. Spherical ZnO NPs with an average size of 20 nm were successfully fabricated at optimal synthesis conditions using 35 ml of barberry extract and 30 min reaction time. ZnO NPs were determined to have a zeta potential of –15.3 mV and an antioxidant activity of 28.8%. The antibacterial activity of fabricated ZnO NPs was tested againstStaphylococcus aureusand found to possess significant (p<0.05) inhibitory effect against this microorganism.

Biofabrication of zinc oxide nanoparticles using fruit extract of Rosa canina and their toxic potential against bacteria: A mechanistic approach

The use of plant extract in the biosynthesis of nanoparticles (NPs) can be an eco-friendly approach and have been suggested as a possible alternative to classic methods namely physical and chemical procedures. In this study, the biosynthesis of zinc oxide (ZnO) NPs by both “conventional heating” (CH) and “microwave irradiation” (MI) methods has been reported. Stable and spherical ZnONPs were produced using zinc nitrate and flesh extract of Rosa canina fruit (rosehip) which was used as a precursor. The flesh extract acts as a reducing and capping agent for generation of ZnONPs. The structural, morphological and colloidal properties of the as-synthesized NPs have been confirmed by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX), Fourier transform Infrared (FT-IR) and Dynamic Light Scattering (DLS). In comparison with the CH method, the MI method has some advantages such as significantly short reaction time (within 8min) owing to the high heating rate and thus the accelerated reaction rate. Both methods led to the synthesis of nearly identical NPs with respect to shape and size according to the results of DLS, XRD and SEM techniques. The possible mechanism for synthesis pathway has been proposed based on FT IR results, XRD patterns, potentiometric data and antioxidant activity. In addition, the antibacterial activity of as-prepared ZnONPs was investigated against several bacteria such as Listeria monocytogenes, Escherichia coli, Salmonella typhimurium. Moreover, the efficacy of ZnONPs to treat cancer cell lines were measured by means of cell viability test via MTT assay in which concentrations of 0.05 and 0.1mg/mL of ZnONPs induced a very low toxicity. Thus, the present investigation reveals that ZnONPs have the potential for various medical and industrial applications.

Honey-based synthesis of ZnO nanopowders and their cytotoxicity effects

The use of food and bio-derived products for the synthesis of different nanomaterials is of enormous interest to modern nanobiotechnology. We have developed a simple, novel, “greener”, bio-directed, and low cost method for the synthesis of zinc oxide nanopowders (ZnO–NPs) by using honey as a food and bio-derived product. The prepared ZnO–NPs were characterized by UV–visible spectroscopy (UV–vis), field emission scanning electron microscopy (FESEM), thermogravimetric analysis and differential thermal analysis (TGA/DTA), and powder X-ray diffraction (PXRD). Spherical ZnO–NPs were synthesized at different calcination temperatures and FESEM images and its corresponding particle size distributions showed the formation of nanopowders in size of about 30nm. The PXRD analysis revealed wurtzite hexagonal ZnO with preferential orientation at (101) reflection plane. In vitro cytotoxicity studies on neuro2A cells showed a dose dependent toxicity with non-toxic effect of a concentration up to 7.8μg/mL.