Biofabrication and Characterization of Zinc Oxide Nanoparticles Using Staphylococcus aureus

Zinc oxide (ZnO) nanoparticles have wide-ranging applications in a diverse array of industrial and consumer products, from ceramic manufacture and paint formulation to sunscreens and haircare products. Hence, it is imperative to rigorously characterize the health and safety aspects of human exposure to ZnO nanoparticles. This study therefore evaluated the cellular association, cytotoxic and inflammatory potential of spherical and sheet-shaped ZnO nanoparticles (of approximately the same specific surface area ≈30 cm²/g) on mouse and human cell lines (RAW-264.7 and BEAS-2B respectively), as well as with primary cultures of mouse bone marrow-derived dendritic cells (DC). The WST-8 assay demonstrated dose-dependent effects on the cytotoxicity of spherical and sheet-shaped ZnO nanoparticles on both RAW-264.7 and BEAS-2B cells, even though there was no significant effect of shape on the cytotoxicity of ZnO nanoparticles. There was however higher cellular association of spherical versus sheet-shaped ZnO nanoparticles. Measurement of reactive oxygen species (ROS) with the 2',7'-dichlorfluorescein-diacetate (DCFH-DA) assay indicated up to 4-folds increase in ROS level upon exposure to ZnO nanoparticles, but there was again no significant difference between both ZnO nanoparticle shapes. Exposure of primary dendritic cells to ZnO nanoparticles upregulated expression of CD80 and CD86 (well-known markers of DC activation and maturation) and stimulated release of pro-inflammatory cytokines--IL-6 and TNF-α, thus pointing to the potential of ZnO nanoparticles in inducing inflammation. Hence, our study indicated that ZnO nanoparticles can have potential detrimental effects on cells even at dosages where there are little or no observable cytotoxic effects.

This study was conducted to evaluate the effects of adding cinnamon nanoparticles (NPs), Zinc oxide (ZnO) nanoparticles (NPs), and Copper oxide (CuO) NPs on the antibacterial property of a luting and lining glass ionomer cement (GIC) that was used for the cementation of orthodontic bands to the tooth. Cinnamon NPs, ZnO NPs, and CuO NPs were added into a luting and lining GIC in weight percentages of 1%, 2%, and 4%, respectively while a non-modified GIC was considered as the control group. Agar disc diffusion test was applied to assess the antimicrobial property of samples against Streptococcus mutans (S. mutans). The cytotoxicity of the nanoparticles was examined through the MTT assay for gingival fibroblasts. Data showed that GIC containing cinnamon and ZnO NPs displayed a larger inhibition zone diameter and greater antibacterial activity against S. mutans than CuO NPs. Meanwhile, there were no significant differences in the inhibition zone diameter of cinnamon NPs and ZnO NPs. The cytotoxicity assessment revealed the lower cytotoxicity of cinnamon NPs and the higher cytotoxicity of CuO NPs while the cytotoxicity of ZnO NPs was observed to be higher than cinnamon NPs and lower than CuO NPs. GIC containing cinnamon NPs exhibited noticeable antibacterial activity against S. mutans and cinnamon NPs revealed less cytotoxicity and it is can be labeled as a favorable option for further assessment to be applied in fixed orthodontic treatments for the cementation of bands to teeth.

Synthesis, characterization and cytotoxicity of zinc oxide nanoparticles by green synthesis method

Comparative analysis of biological activities of green-synthesized silver and zinc oxide nanoparticles using <i>Pogonatherum crinitum</i> extracts

The present study was aimed to investigate the dose-dependent effect of zinc oxide (ZnO) nanoparticles on antioxidant enzyme activities and messenger RNA (mRNA) expression in the cocultured C2C12 and 3T3-L1 cells. Coculturing experiments are 3D and more reliable compared to mono-culture (2D) experiment. Even though, there are several studies on ZnO nanoparticle-mediated cytotoxicity, but there are no studies on the effect of ZnO nanoparticle on antioxidant enzyme activities and mRNA expression in the cocultured C2C12 and 3T3-L1 cells. A cytotoxicity assay was carried out to determine the effect of ZnO nanoparticles on the C2C12 and 3T3-L1 cell viability. At higher concentration of ZnO nanoparticles, C2C12 and 3T3-L1 cells almost die. ZnO nanoparticles increased reactive oxygen species (ROS) and lipid peroxidation and reduced glutathione (GSH) levels in a dose-dependent manner in the C2C12 and 3T3-L1 cells. In addition, ZnO nanoparticles increased antioxidant enzyme activities and their mRNA expression in the C2C12 and 3T3-L1 cells. In conclusion, the present study showed that ZnO nanoparticles increased oxidative stress, antioxidant enzyme activities, and their mRNA expression in the cocultured C2C12 and 3T3-L1 cells.

In vitro cytotoxicity of hydrothermally synthesized ZnO nanoparticles on human periodontal ligament fibroblast and mouse dermal fibroblast cells

Phosphate-enhanced cytotoxicity of zinc oxide nanoparticles and agglomerates

Zinc oxide (ZnO) nanoparticles (NPs) are utilized as a zinc (Zn) fortifier in processed foods where diverse food additives can be present. Among them, additive solvents may strongly interact with ZnO NPs by changing the dispersion stability in food matrices, which may affect physico-chemical and dissolution properties as well as the cytotoxicity of ZnO NPs. In this study, ZnO NP interactions with representative additive solvents (methanol, glycerin, and propylene glycol) were investigated by measuring the hydrodynamic diameters, solubility, and crystallinity of ZnO NPs. The effects of these interactions on cytotoxicity, cellular uptake, and intestinal transport were also evaluated in human intestinal cells and using in vitro human intestinal transport models. The results revealed that the hydrodynamic diameters of ZnO NPs in glycerin or propylene glycol, but not in methanol, were significantly reduced, which is probably related to their high dispersion and increased solubility under these conditions. These interactions also caused high cell proliferation inhibition, membrane damage, reactive oxygen (ROS) generation, cellular uptake, and intestinal transport. However, the crystal structure of ZnO NPs was not affected by the presence of additive solvents. These findings suggest that the interactions between ZnO NPs and additive solvents could increase the dispersion and solubility of ZnO NPs, consequently leading to small hydrodynamic diameters and different biological responses.

Plant-mediated synthesis of zinc oxide (ZnO) nanoparticles using Alnus nepalensis D. Don for biological applications

< p>The Aim of this study is to examine the in vitro antibacterial and cytotoxicity activities of green synthesized Zinc Oxide (ZnO) nanoparticles using leaf aqueous extract of Allamanda cathartica (L). Zinc nitrate acts as a precursor and aqueous leaf extract chemical reducing agent. Green synthesized ZnO nanoparticles are verified by an analysis of the powder X-ray diffraction. The FTIR study indicates the presence of different functional groups in the leaf extract as well as in the ZnO nanoparticles. The UV absorption wavelength was measured at a high of 360 nm. The crystalline size, shape and surface morphology of ZnO nanoparticles are measured using Field Emission Scanning Electron Microscopy (FE-SEM). The EDAX spectrum conform that zinc and oxygen were present in the ZnO nanoparticles. Green synthesized ZnO nanoparticles exhibited attractive antibacterial activity against clinical bacillus sp. The anticancer activity of ZnO nanoparticles is also tested against Human breast cancer MCF7 cell and were significantly reduced the proliferation of MCF7 cell comparison with the control cell viability.

This study aimed to assess the efficacy of starch-based zinc oxide nanoparticles (ZnO-NPs) against methicillin-resistant Staphylococcus aureus (MRSA) isolates from clinical specimens in Basrah, Iraq. In this cross-sectional study, 61 MRSA were collected from different clinical specimens of patients in Basrah city, Iraq. MRSA isolates were identified using standard microbiology tests, cefoxitin disc diffusion and oxacillin salt agar. ZnO-NPs were synthesized in three different concentrations (0.1 M, 0.05 M, 0.02 M) by the chemical method using starch as the stabilizer. Starch-based ZnO-NPs were characterized using ultraviolet–visible spectroscopy (UV-Vis), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). The antibacterial effects of particles were investigated by the disc diffusion method. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the most effective starch-based ZnO-NPs were determined using a broth microdilution assay. The UV-Vis of all concentrations of starch-based ZnO-NPs exhibited a strong absorption band at 360 nm which was characteristic of the ZnO-NPs. XRD assay confirmed the representative hexagonal wurtzite phase of the starch-based ZnO-NPs, and their purity and high crystallinity. The spherical shape with a diameter of 21.56 ± 3.42 and 22.87 ± 3.91 was revealed for the particles by FE-SEM and TEM, respectively. EDS analysis confirmed the presence of zinc (Zn) (61.4 ± 0.54%) and oxygen (O) (36 ± 0.14%). The 0.1 M concentration had the highest antibacterial effects (mean ± SD of inhibition zone = 17.62 ± 2.65 mm) followed by the 0.05 M concentration (16.03 ± 2.24 mm) and the 0.02 M concentration (12.7 ± 2.57 mm). The MIC and the MBC of the 0.1 M concentration were in the range of 25–50 µg/mL and 50–100 µg/mL, respectively. Infections caused by MRSA can be treated with biopolymer-based ZnO-NPs as effective antimicrobials.

Fabrication of heterojunction semiconductors for the photodegradation of toxic organic dyes under sunlight exposure has earned significant recognition from researchers nowadays. On that account, we have synthesized and explored a comparative photodegradation study of ZnO/CuO nanocomposite with ZnO and CuO nanoparticles. ZnO and CuO nanoparticles have been synthesized by biosynthesis methods usingFicus benghalensisleaf extract. As-synthesized ZnO and CuO nanoparticles have been further utilized for the synthesis of ZnO/CuO nanocomposite by the mortar pestle crushing/milling method. Both biosynthesis methods and mortar pestle crushing/milling methods are simple, low-cost, and environmentally friendly. Structural, optical, and morphological analysis of all the synthesized nanomaterials havebeen doneby powder X-ray diffraction (PXRD), scanning electron microscopy (SEM),transmission electron microscopy (TEM),Brunauer-Emmett-Teller (BET),field emission scanning electron microscopy (FESEM), energy-dispersive spectroscopy (EDS), fourier transform infrared spectroscopy (FTIR), and UV-visible spectroscopy.PXRD data reveal that synthesized ZnO nanoparticles are in the hexagonal wurtzite phase, CuO nanoparticles in the monoclinic phase, and ZnO/CuO nanocomposite in the hexagonal wurtzite as well as in monoclinic phase. FE-SEM and TEM images of ZnO/CuO nanocomposite reveal the nanorod-shaped morphology along with micro-sized and nano-sized flakes. The BET analysis shows the surface areas 18.128 m2/g for ZnO nanoparticles, 16.653 m2/g for CuO nanoparticles, and 19.580 m2/g for ZnO/CuO nanocomposite, respectively. Theenergyband gap values of ZnO/CuO nanocomposite are obtained 3.13eV for ZnO and 2.76eV for CuO, respectively. The photocatalytic behaviors of all the synthesized nanomaterialsareexamined against aqueous dye solutions of methylene blue (MB), rhodamine B (RhB), and methyl orange (MO) under sunlight irradiation. The results reveal that the photocatalytic degradation efficiency of ZnO/CuO nanocompositehasbeen found higher than with ZnO and CuO nanoparticles for all the dyes. Also, all the synthesized nanomaterialsindicatehigher photocatalytic degradation efficiency for methylene blue dye among allthreedyes. The kinetics of photodegradation of all the dye solutions has also been investigated in the presence of ZnO, CuO, and ZnO/CuO photocatalysts separately. The results exhibit that rate constant values for all the dyes are higher with ZnO/CuOnanocompositethan with ZnO and CuOnanoparticles.ZnO/CuO nanocomposite demonstrates degradation efficiency for MB dye99.13%, for RhB80.21%, and for MO67.22%after 180min of sunlight exposure.ZnO/CuO nanocomposite and ZnO and CuO nanoparticles also show thebestreusability and stability up to three cycles for photocatalytic degradation of MB dyes amongall the dyes.Therefore, green synthesized ZnO/CuO nanocomposite could be used asan efficientphotocatalyst for the degradation of various toxic dyes.The mineralization of different dyes using ZnO/CuO nanocomposite has been examined by FTIR analysis. Furthermore, the mineralizationof MB dye has been done by total organic carbon (TOC)measurements.

Effect of humic acids and sunlight on the cytotoxicity of engineered zinc oxide and titanium dioxide nanoparticles to a river bacterial assemblage

Nanostructured particles offer outstanding diversities of applications in the fields of nanotechnology, nano-engineering, nano-biotechnology, etc. Morphological structure, size distribution, electronic behavior including intrinsic characteristics of nanoparticles depend on the source and synthesis methods. Here, an eco-friendly approach using microwave irradiation for the synthesis of zinc oxide (ZnO) nanoparticles has been reported. Zinc nitrate was used as a precursor whereas starch and D-glucose were used as capping and reducing agent, respectively. The synthesized nanoparticles were characterized by different instrumental methods including Ultraviolet-Visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), and field emission scanning electron microscopy (FE-SEM). The characteristic λmax at 373 nm for ZnO nanoparticles was recorded from UV-Vis absorption spectrum in aqueous system. FT-IR spectrum showed a very sharp peak at 476.62 cm-1 which confirmed the presence of Zn-O bond. The prepared ZnO was highly crystalline having wurtzite structure and the crystallite size was calculated to be 24.41 nm obtained from XRD analysis. FE-SEM images showed that the synthesized ZnO nanoparticles had near- spherical morphology and particle size was found in the range of 40–90 nm. The antibacterial and anti-biofilm application of ZnO nanoparticles were studied and inhibition zones of Gram negative Salmonella typhi (S. typhi), Klebsiella spp., Escherichia coli (E. coli) and Gram positive Staphylococcus aureus (S. aureus)- 8a were found to be 11 mm, 12 mm, 11.5 mm and 13.5 mm, respectively. Besides, ZnO nanoparticles also showed excellent photocatalytic activity against methylene blue dye solution. The easy and eco-friendly fabrication method would play vital role in other nanoparticles synthesis to meet the demand in textile industry, agriculture and medical sectors.

Extracellular biosynthesis of zinc oxide nanoparticles using Rhodococcus pyridinivorans NT2: Multifunctional textile finishing, biosafety evaluation and in vitro drug delivery in colon carcinoma