The in vivo kinetics of nanoparticles is an essential to understand the hazard of nanoparticles. Here, the absorption, distribution, and excretion patterns of titanium dioxide (TiO2) and zinc oxide ...(ZnO) nanoparticles following oral administration were evaluated.
Nanoparticles were orally administered to rats for 13 weeks (7 days/week). Samples of blood, tissues (liver, kidneys, spleen, and brain), urine, and feces were obtained at necropsy. The level of Ti or Zn in each sample was measured using inductively coupled plasma-mass spectrometry.
TiO₂ nanoparticles had extremely low absorption, while ZnO nanoparticles had higher absorption and a clear dose-response curve. Tissue distribution data showed that TiO₂ nanoparticles were not significantly increased in sampled organs, even in the group receiving the highest dose (1041.5 mg/kg body weight). In contrast, Zn concentrations in the liver and kidney were significantly increased compared with the vehicle control. ZnO nanoparticles in the spleen and brain were minimally increased. Ti concentrations were not significantly increased in the urine, while Zn levels were significantly increased in the urine, again with a clear dose-response curve. Very high concentrations of Ti were detected in the feces, while much less Zn was detected in the feces.
Compared with TiO₂ nanoparticles, ZnO nanoparticles demonstrated higher absorption and more extensive organ distribution when administered orally. The higher absorption of ZnO than TiO₂ nanoparticles might be due to the higher dissolution rate in acidic gastric fluid, although more thorough studies are needed.
•ZnO nanoparticles are an emerging novel nanomaterial.•It exhibits effects by inducing ROS generation and causing apoptosis.•It shows synergistic and enhanced therapeutic efficacy when combined with ...other therapeutic agents.•ZnO nanoparticles have also been explored as drug carriers for anti-cancer drugs.•Toxicity concern needs to be explored before clinical applications.
Zinc oxide (ZnO) nanoparticles (NPs) are a promising platform for use in biomedical research, especially given their anticancer and antimicrobial activities. These activities are associated with the ability of ZnO NPs to generate reactive oxygen species (ROS) and induce apoptosis. In addition, ZnO NPs have been successfully exploited as drug carriers for loading and transporting drugs to target sites, thereby reducing unwanted toxicity and off-target effects, and resulting in amplified synergistic effects. Here, we discuss the synthesis and biomedical applications of ZnO NPs.
The study aimed to find an effective method for fungal-mediated synthesis of zinc oxide nanoparticles using endophytic fungal extracts and to evaluate the efficiency of synthesized ZnO NPs as ...antimicrobial and anticancerous agents.
Zinc oxide nanoparticles (ZnO NPs) were produced from zinc nitrate hexahydrate with fungal filtrate by the combustion method. The spectroscopy and microscopy techniques, such as ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM) with selected area electron diffraction (SAED), were used to characterize the obtained product. Antibacterial activity on Gram-positive (
and
) and Gram-negative (
and
) samples was tested by broth microplate dilution technique. ZnO NPs antifungal activity was determined against plant pathogenic and regular contaminating fungi using the food-poison method. The anticancerous assay of the synthesized ZnO NPs was also investigated by cell uptake, MTT assay, and apoptosis assay.
The fungal synthesized ZnO NPs were pure, mainly hexagonal in shape and size range of 34-55 nm. The biosynthesized ZnO NPs could proficiently inhibit both Gram-positive and Gram-negative bacteria. ZnO NPs synthesized from fungal extract exhibited antifungal activity in a dose-dependent manner with a high percentage of mycelial inhibition. The cell uptake analysis of ZnO NPs suggests that a significant amount of ZnO NPs (1 μg/mL) was internalized without disturbing cancer cells' morphology. As a result, the synthesized ZnO NPs showed significant anticancer activity against cancer cells at 1 μg/mL concentration.
This fungus-mediated synthesis of ZnO NPs is a simple, eco-friendly, and non-toxic method. Our results show that the synthesized ZnO NPs are an excellent novel antimicrobial and anticancer agent. Further studies are required to understand the mechanism of the antimicrobial, anticancerous action of ZnO NPs and their possible genotoxicity.
Zinc oxide (ZnO) is an attractive semiconductor material for photocatalytic applications, owing to its opto-electronic properties. Its performances are, however, strongly affected by the surface and ...opto-electronic properties (i.e., surface composition, facets and defects), in turn related to the synthesis conditions. The knowledge on how these properties can be tuned and how they are reflected on the photocatalytic performances (activity and stability) is thus essential to achieve an active and stable material. In this work, we studied how the annealing temperature (400 °C vs. 600 °C) and the addition of a promoter (titanium dioxide, TiOsub.2) can affect the physico-chemical properties of ZnO materials, in particular surface and opto-electronic ones, prepared through a wet-chemistry method. Then, we explored the application of ZnO as a photocatalyst in COsub.2 photoreduction, an appealing light-to-fuel conversion process, with the aim to understand how the above-mentioned properties can affect the photocatalytic activity and selectivity. We eventually assessed the capability of ZnO to act as both photocatalyst and COsub.2 adsorber, thus allowing the exploitation of diluted COsub.2 sources as a carbon source.
The synthesis of metal oxide nanoparticles with the use of plant extract is a promising alternative to the conventional chemical method. This work aimed to synthesize zinc oxide nanoparticles ...(ZnONPs) using plant extract of chamomile flower (Matricaria chamomilla L.), olive leave (Olea europaea) and red tomato fruit (Lycopersicon esculentum M.). The synthesized ZnONPs were characterized by UV-Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) with EDS profile. The XRD studies confirmed the presence of pure crystalline shapes of ZnO nanoparticles. The ZnONPs synthesized by Olea europaea had the least size range of 40.5 to 124.0 nm as revealed by the SEM observation while XRD revealed a dominant average size of 48.2 nm in the sample which is similar to the size distribution analysis obtained from TEM. The antibacterial effect of ZnONPs synthesized by Olea europaea on Xanthomonas oryzae pv. oryzae (Xoo) strain GZ 0003 had an inhibition zone of 2.2 cm at 16.0 µg/ml which was significantly different from ZnONPs synthesized by Matricaria chamomilla and Lycopersicon esculentum. Also, the bacterial growth, biofilm formation, swimming motility and bacterial cell membrane of Xoo strain GZ 0003 were significantly affected by ZnO nanoparticle. Overall, zinc oxide nanoparticles are promising biocontrol agents that can be used to combat bacterial leaf blight diseases of rice.
Colorectal cancer is a common malignancy occurring in the digestive system and ranks second in cancer mortality worldwide. In colorectal cancer, hydrogen sulfide (H
S) is selectively upregulated, ...resulting in the further exacerbation of the disease. Therefore, the clearance of H
S and the regulation of the enzymes on the H
S pathways are of great significance for colorectal cancer therapy.
Here, we investigated the H
S content in various clinical tumor tissues from patients and confirmed that overproduced concentration of H
S in colorectal cancer. Accordingly, we developed an H
S-responsive nanoplatform based on zinc oxide coated virus-like silica nanoparticles (VZnO) for the therapy of colorectal cancer.
Owing to its excellent H
S scavenging ability, VZnO could effectively reduce H
S content in colorectal cancer to prohibit the growth of CT26 and HCT116 colorectal cancer cells. Moreover, the removal of H
S in colorectal cancer also leads to tumor inhibition through activating ferroptosis, a non-apoptotic form of cell death. The biosafety-related toxicological and pathological analysis confirmed the low toxicity and high safety of VZnO in colorectal cancer treatment. Furthermore, as an H
S-responsible nanosystem, VZnO appears to have no therapeutic effect on other non H
S rich cancers, such as the 4T1 breast cancer model.
We anticipate that the H
S-depletion-induced ferroptosis strategy using zinc oxide-based nanomaterials would provide insights in designing nanomedicines for colorectal cancer-target theranostics and may offer clinical promise.
Zinc oxide nanoparticles (ZnO NPs) are nanomaterials that are widely used in many fields. ZnO NPs are ion-shedding particles, and zinc ions produce important and potent effects that differ from those ...of other metal or metal oxide NPs. Several studies have reported the toxicological effects of ZnO NPs administered via several different routes, including orally, dermally, by pulmonary absorption, intraperitoneally, and intravenously. Some potential routes for human exposure have produced various toxic effects in animal models. Moreover, several in vitro studies using a range of cell lines have reported the mechanisms underlying ZnO NP toxicity. Zinc ions play a very important role in ZnO NP toxicity, although the effects of the particulate form cannot be excluded. A crucial determinant of toxicity is the solubility of ZnO NPs, which is influenced by various factors, including the pH of the environment in tissues, cells, and organelles. In addition to the inflammatory responses and oxidative stress known to be induced by ZnO NPs, these NPs also exhibit some positive anti-inflammatory, anti-diabetic, and pro-coagulant effects at sub-toxic doses; these effects are probably induced by zinc ions, which are an essential element in cell homeostasis. It is highly likely that there are additional distinct mechanisms at sub-toxic doses and concentrations, which may be concealed or altered by the toxic effects observed at higher levels of ZnO NPs. Furthermore, many signaling pathway molecules associated with necrosis and apoptosis can be activated, leading to cell death. This review presents the status of ZnO NP toxicology and highlights areas requiring further investigation.
Background: To overcome some of the disadvantages of the current primary root canal obturating materials, there is a continued interest in search for chemical compounds with broader and more ...effective antibacterial action and less cytotoxicity. Aim: This study aimed to evaluate and compare in vivo the clinical and radiographic success of mixtures of zinc oxide-Ocimum sanctum extract, zinc oxide-ozonated oil, and zinc oxide-eugenol (ZOE) as obturating materials in pulpectomy of primary molars. Settings and Design: This was an in vivo randomized controlled clinical trial. Materials and Methods: Ninety primary molars selected were randomly divided into three groups. Group A was obturated with zinc oxide-O. sanctum extract, Group B with zinc oxide-ozonated oil, and Group C with ZOE. All the groups were evaluated for success or failure based on clinical and radiographic criteria at the end of 1, 6, and 12 months. Statistical Analysis Used: The intra- and inter-examiner reliability of the first and the second co-investigators was calculated by Cohen's kappa statistic. The data were analyzed using Chi-square test, P ≤ 0.05 (indicates statistical significance). Results: By the end of 12 months, the overall clinical success rate was 88%, 95.7%, and 90.9% in Groups A, B, and C, respectively; whereas the radiographic success rate was found to be 80%, 91.3%, and 86.4% in Groups A, B, and C, respectively. Conclusion: On the basis of the overall success rates of all the three obturating materials, the following order of performance can be concluded: zinc oxide-ozonated oil > ZOE > zinc oxide-O. sanctum extract.
Our current mechanistic understanding on the effects of engineered nanoparticles (NPs) on cellular physiology is derived mainly from 2D cell culture studies. However, conventional monolayer cell ...culture may not accurately model the mass transfer gradient that is expected in 3D tissue physiology and thus may lead to artifactual experimental conclusions. Herein, using a micropatterned agarose hydrogel platform, the effects of ZnO NPs (25 nm) on 3D colon cell spheroids of well‐defined sizes are examined. The findings show that cell dimensionality plays a critical role in governing the spatiotemporal cellular outcomes like inflammatory response and cytotoxicity in response to ZnO NPs treatment. More importantly, ZnO NPs can induce different modes of cell death in 2D and 3D cell culture systems. Interestingly, the outer few layers of cells in 3D model could only protect the inner core of cells for a limited time and periodically slough off from the spheroids surface. These findings suggest that toxicological conclusions made from 2D cell models might overestimate the toxicity of ZnO NPs. This 3D cell spheroid model can serve as a reproducible platform to better reflect the actual cell response to NPs and to study a more realistic mechanism of nanoparticle‐induced toxicity.
Cellular nanotoxicological responses are largely dependent on the cell dimensionality. Cells in a 3D configuration possess similar cell–cell and cell–extracellular matrix interactions as the actual tissue, making it a useful platform to assess any potential toxicological effects of the nanoparticles to the biological system. In this 3D spheroid model, outer layer of cells acts as sacrificial layer to protect the unexposed inner cells from the direct toxic effects of ZnO nanoparticles.
Zinc oxide nanoparticles (ZnO NPs) were synthesized using Ziziphus nummularia leaf extract. The characterization was done by various spectral analysis and antifungal (anti-candidal) activity against ...multidrug resistant clinical isolates and their cytotoxic potential was evaluated. The ZnO NPs were 17.33 nm in size and were spherical/irregular in shape. The antifungal activity of ZnO NPs was better than four standard azole antibiotics and they also showed potent cytotoxic effect against HeLa cancer cell line. The results strongly suggest the applicability of green synthesized ZnO NPs as antifungal agent and also its use in cancer diagnosis and treatment.
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