Use Of Nanoceria Research Articles

Nanoceria Anti-inflammatory and Antimicrobial Nanodrug: Cellular and Molecular Mechanism of Action.

Nanoceria is a well-known nanomaterial with various properties, including antioxidant, proangiogenic, and therapeutic effects. Despite its potential, there are still aspects that require further exploration, particularly its anti-inflammatory and antimicrobial activities. The global demand for novel anti-inflammatory and antimicrobial drugs underscores the significance of understanding nanoceria in both contexts. In this study, we evaluated the effect of nanoceria on macrophage polarization to better understand its anti-inflammatory effects. Additionally, we investigated the mechanism of action of nanoceria against Cryptococcus neoformans (ATCC 32045), Candida parapsilosis (ATCC 22019), Candida krusei (ATCC 6258), and Candida albicans. The results demonstrated that nanoceria can polarize macrophages toward an anti-inflammatory profile, revealing the cellular mechanisms involved in the anti-inflammatory response. Concerning the antimicrobial effect, it was observed that nanoceria have a more pronounced impact on Candida parapsilosis, leading to the formation of pronounced pores on the surface of this species. Finally, biochemical analysis revealed transitory alterations, mainly in liver enzymes. The data support the use of nanoceria as a potential anti-inflammatory and antimicrobial drug and elucidate some of the mechanisms involved, shedding light on the properties of this nanodrug.

Nanomaterials based on cerium oxide nanoparticles for wound regeneration: a literature review

Objective: to analyze data on the synthesis and properties of cerium oxide nanoparticles, as well as the prospects of its application in regenerative medicine for wound healing. Methodology. World literature was reviewed using PubMed, SCOPUS, ResearchGate, CyberLeninck, and Elibrary databases, as well as manual searches for authors and reference lists. Key search terms were «cerium oxide» AND nano* AND (healing OR regeneration OR repair) AND wound». The timeline was from the date of publication through August 2023. Results. The final analysis included 59 sources containing information on the synthesis and size of nanoparticles (and/or other physicochemical characteristics), methodology and results of in vivo and in vitro studies on the efficacy and/or safety of nanoceria for wound regeneration. It is shown that despite the progressive growth of research interest over the last 15 years, the actual use of nanoceria in practical medicine is still not widespread. This is due to a wide variety of non-standardized synthesis methods and conditions, resulting in the variability of physicochemical parameters of nanoparticles (size, form), thereby affecting the safety and biomedical efficacy of nanoceria. Regeneration mechanisms, including the antioxidant-prooxidant, anti-inflammatory and antimicrobial effects of nanoceria, which contribute to accelerated wound healing, are discussed. The severity of the regenerative effects depends on the method and conditions of synthesis, hence the resulting physicochemical characteristics of the nanoparticles. Therefore, after each batch, newly synthesized nanoceria needs physicochemical and biomedical experimental tests. Conclusion. Nanoceria has great potential in tissue engineering for regenerative medicine, particularly for healing of various kinds of wounds. Having developed a technology for standardized synthesis for effective and safe nanoceria (of the right form and size) on a production scale, it can be introduced in medicine, possibly improving the outcomes of treatment of many diseases and pathologies. The authors present conclusions on the results of the study of nanoceria for accelerating qualitative regeneration and the requirements for nanoparticles obtained during synthesis.

Chitosan-based multifunctional films reinforced with cerium oxide nanoparticles for food packaging applications

The current study discusses the use of nanoceria as a multifunctional filler in food packaging biopolymer films for the first time. Nanoceria was synthesized using co-precipitation method. Chitosan-based food packaging films incorporated with 1 wt% and 2 wt% nanoceria were prepared and characterized. The FTIR absorption spectra confirms the presence of hydrogen bonding between nanoceria and chitosan structure. The nanocomposite films displayed strong UV-A and UV-B blocking properties besides being mechanically strong, thermally stable and possessing high moisture barrier properties. Further, due to the switching of oxidation states by cerium between Ce3+ and Ce4+, nanoceria shows high photocatalytic activity. This results in strong antimicrobial activity against E. coli and L. monocytogenes, especially under visible light. Further, the nanocomposite films displayed ∼1.25 times and ∼2.3 times higher ABTS and DPPH free radical scavenging potential, respectively, compared to pristine chitosan films, which indicate their high antioxidant potential. Moreover, the films depicted good biocompatibility towards L929 cells indicating their safety for food contact applications. With all these properties, the nanoceria-added chitosan films display strong potential for use in active food packaging, especially for high fat food products such as nuts and meats.

CeO2 Nanoparticle Transformation to Nanorods and Nanoflowers in Acids with Boosted Oxidative Catalytic Activity

Nanoceria (CeO2 nanoparticle) with oxidase-like catalytic activity has been used for a diverse range of analytical, environmental, and nanomedicine applications. In this work, the use of nanoceria ...

Synthesis and Therapeutic Potential of Nanoceria against Cancer: An Update.

Applications of nanoceria in the biomedical field are quite promising, as previous data has shown potential use of nanoceria as therapeutics via radical scavenging and oxidative stress mitigating properties. But, still, there are contradicting reports regarding nanoceria activity, mode of action, and in vitro toxicity in the cell. There are different nanoceria synthesis methods and Ligands for functionalization and loading of nanoceria into drugs for targeted drug delivery. Redox chemistry of nanoceria exerts their anticancer properties through apoptosis and oxidative stress as it can switch between Ce3+ and Ce4+ and act as free radical scavengers. For breast cancer treatment, cerium oxide nanoparticles (CeONPs) can act as protectant for healthy cells against on-going radiotherapy. Similarly, CeONPs were used to make pancreatic cancer cells more sensitive to radiation damage setting them on the apoptotic pathway. Herein, the study reflects the use of nanoceria as a drug delivery system in chemotherapy due to its efficiency in acidic pH and oxidase activity in the microenvironment. A controlled drug delivery system was adapted using a nano-complexes of AMD-GCCNP-DOX, which were then employed against the retinoblastoma cells from the human eye to target the overexpressing chemokine receptor 4 (CXCR4). In radiotherapy, nanoceria acts as radioprotectants due to their free radical scavenging property and inhibit the proliferation and migration of gastric cancer. This paper summarizes the synthesis methods and application of nanoceria in cancer.

Nanoceria supported rhodium(0) nanoparticles as catalyst for hydrogen generation from methanolysis of ammonia borane

This work reports the preparation and catalytic use of nanoceria supported rhodium(0) nanoparticles, Rh(0)/nanoCeO2, as catalyst for hydrogen generation from the methanolysis of ammonia borane. Rh(0)/nanoCeO2 was in situ formed from the reduction of rhodium(II) octanoate on the surface of nanoceria during the catalytic methanolysis of ammonia borane at room temperature. The results of analysis using PXRD, TEM, STEM-EDS, XPS, SEM, SEM-EDX, N2 adsorption-desorption and ICP-OES reveal that rhodium(0) nanoparticles were well dispersed on the surface of nanoceria with an average size of 3.9 ± 0.6 nm. Rh(0)/nanoCeO2 shows high catalytic activity in the methanolysis of ammonia borane with a turnover frequency of 144 min−1. Note that hydrogen generation from the methanolysis of ammonia borane catalyzed by Rh(0)/nanoCeO2 is slightly less than 3.0 equivalent, due to the reduction of Ce4+ ions to Ce3+ ions on the surface of nanoceria during the methanolysis of ammonia borane. The reduction of Ce4+ ions leading to the formation of Ce3+ defects on the surface of nanoceria under the catalytic reaction conditions could be investigated by high resolution Ce 3d XPS analysis. Additionally, the formation kinetic of rhodium(0) nanoparticles could be studied by using the hydrogen generation from the methanolysis of ammonia borane as reporter reaction; thus, the rate constants for the slow nucleation, k1 and autocatalytic surface growth of rhodium(0) nanoparticles, k2 were determined. Our report also includes the results of kinetic study of the catalytic methanolysis of ammonia borane depending on rhodium concentration and temperature.

PH-Controlled Cerium Oxide Nanoparticle Inhibition of Both Gram-Positive and Gram-Negative Bacteria Growth

Here, the antibacterial activity of dextran-coated nanoceria was examined against Pseudomonas aeruginosa and Staphylococcus epidermidis by varying the dose, the time of treatment, and the pH of the solution. Findings suggested that dextran-coated nanoceria particles were much more effective at killing P. aeruginosa and S. epidermidis at basic pH values (pH = 9) compared to acidic pH values (pH = 6) due to a smaller size and positive surface charge at pH 9. At pH 9, different particle concentrations did cause a delay in the growth of P. aeruginosa, whereas impressively S. epidermidis did not grow at all when treated with a 500 μg/mL nanoceria concentration for 24 hours. For both bacteria, a 2 log reduction and elevated amounts of reactive oxygen species (ROS) generation per colony were observed after 6 hours of treatment with nanoceria at pH 9 compared to untreated controls. After 6 hours of incubation with nanoceria at pH 9, P. aeruginosa showed drastic morphological changes as a result of cellular stress. In summary, this study provides significant evidence for the use of nanoceria (+4) for a wide range of anti-infection applications without resorting to the use of antibiotics, for which bacteria are developing a resistance towards anyway.

A single use electrochemical sensor based on biomimetic nanoceria for the detection of wine antioxidants

We report the development and characterization of a disposable single use electrochemical sensor based on the oxidase-like activity of nanoceria particles for the detection of phenolic antioxidants. The use of nanoceria in the sensor design enables oxidation of phenolic compounds, particularly those with ortho-dihydroxybenzene functionality, to their corresponding quinones at the surface of a screen printed carbon electrode. Detection is carried out by electrochemical reduction of the resulting quinone at a low applied potential of −0.1V vs the Ag/AgCl electrode. The sensor was optimized and characterized with respect to particle loading, applied potential, response time, detection limit, linear concentration range and sensitivity. The method enabled rapid detection of common phenolic antioxidants including caffeic acid, gallic acid and quercetin in the µM concentration range, and demonstrated good functionality for the analysis of antioxidant content in several wine samples. The intrinsic oxidase-like activity of nanoceria shows promise as a robust tool for sensitive and cost effective analysis of antioxidants using electrochemical detection.

Catalytic Properties and Biomedical Applications of Cerium Oxide Nanoparticles.

Cerium oxide nanoparticles (Nanoceria) have shown promise as catalytic antioxidants in the test tube, cell culture models and animal models of disease. However given the reactivity that is well established at the surface of these nanoparticles, the biological utilization of Nanoceria as a therapeutic still poses many challenges. Moreover the form that these particles take in a biological environment, such as the changes that can occur due to a protein corona, are not well established. This review aims to summarize the existing literature on biological use of Nanoceria, and to raise questions about what further study is needed to apply this interesting catalytic material to biomedical applications. These questions include: 1) How does preparation, exposure dose, route and experimental model influence the reported effects of Nanoceria in animal studies? 2) What are the considerations to develop Nanoceria as a therapeutic agent in regards to these parameters? 3) What biological targets of reactive oxygen species (ROS) and reactive nitrogen species (RNS) are relevant to this targeting, and how do these properties also influence the safety of these nanomaterials?

266 BIOCOMPATIBILITY OF NANOCERIA IN RAM SPERM DURING 24 HOURS OF INCUBATION

In recent years, there has been increasing interest in nanoparticles, especially those widely present in our environment. Several studies have been performed to evaluate their potential toxic effect and their possible use for biomedical applications. Among others, cerium dioxide nanoparticles (nanoceria, CeO2 ENPs) have been recently investigated for their use in biomedicine, based on their potential antioxidant function, due to the presence of oxygen vacancies and redox transformations (Ce4+/Ce3+) occurring at the surface. However, little is known about the potential toxicity of nanoceria in the reproductive system and on gametes, and no information is available with regard to its biocompatibility and potential toxicity on male gametes. The aim of the present study was to investigate effects of increasing doses of CeO2 ENPs on ram spermatozoa during 24 h storage at 4°C, based on assessment of main kinematic parameters, membranes and DNA integrity, ROS production, mitochondrial activity, and CeO2 intracellular uptake. The ejaculates of 3 rams of proven fertility were pooled and incubated with increasing doses of nanoceria (0, 22, 44, and 220 µg mL–1) up to 24 h at 4°C. The experiment was conducted in 4 replicates. At 0, 2, and 24 h of incubation, the 4 groups were submitted to the following analyses: i) main kinematic parameters (total motility and progressive motility) through CASA (computer-assisted sperm analysis); ii) acrosome and membrane integrity (propidium iodide + Pisum sativum agglutinin staining, PI+PSA); iii) flow cytometry for sperm chromatin structure assay (SCSA, acridine orange staining), mitochondrial activity (Mitotracker Orange), and ROS production (H2DCFDA). Moreover, an aliquot of semen from each group in each time step was fixed and processed for transmission electron microscopy to assess intracellular uptake of CeO2 nanoparticles by spermatozoa. Increasing concentrations of nanoceria did not affect the main kinematic parameters of ram semen; there were no differences in total and progressive motility among groups at any time point during the 24 h of incubation (P > 0.05). Integrity of the acrosome and cytoplasmic membranes, assessed through PI+PSA staining, was not affected by nanoceria in any group (P > 0.05). Moreover, exposure to nanoparticles did not increase DNA fragmentation (P > 0.05), and there was no difference in the amount of ROS produced and mitochondrial activity within the 24 h of incubation with nanoceria (P > 0.05). Absence of internalization of the nanoparticles by spermatozoa and occasional interaction between the sperm surface and nanoceria were observed by transmission electron microscopy analysis. In the present study, exposure of ram spermatozoa to increasing doses of nanoceria was not cytotoxic; furthermore, high concentrations of these nanoparticles were well tolerated. These data open new perspectives on the biomedical use of nanoceria and provide more information about their impact on male gametes.

Ceria nanoparticles stabilized by organic surface coatings activate the lysosome-autophagy system and enhance autophagic clearance.

Cerium oxide nanoparticles (nanoceria) are widely used in a variety of industrial applications including UV filters and catalysts. The expanding commercial scale production and use of ceria nanoparticles have inevitably increased the risk of release of nanoceria into the environment as well as the risk of human exposure. The use of nanoceria in biomedical applications is also being currently investigated because of its recently characterized antioxidative properties. In this study, we investigated the impact of ceria nanoparticles on the lysosome-autophagy system, the main catabolic pathway that is activated in mammalian cells upon internalization of exogenous material. We tested a battery of ceria nanoparticles functionalized with different types of biocompatible coatings (N-acetylglucosamine, polyethylene glycol and polyvinylpyrrolidone) expected to have minimal effect on lysosomal integrity and function. We found that ceria nanoparticles promote activation of the transcription factor EB, a master regulator of lysosomal function and autophagy, and induce upregulation of genes of the lysosome-autophagy system. We further show that the array of differently functionalized ceria nanoparticles tested in this study enhance autophagic clearance of proteolipid aggregates that accumulate as a result of inefficient function of the lysosome-autophagy system. This study provides a mechanistic understanding of the interaction of ceria nanoparticles with the lysosome-autophagy system and demonstrates that ceria nanoparticles are activators of autophagy and promote clearance of autophagic cargo. These results provide insights for the use of nanoceria in biomedical applications, including drug delivery. These findings will also inform the design of engineered nanoparticles with safe and precisely controlled impact on the environment and the design of nanotherapeutics for the treatment of diseases with defective autophagic function and accumulation of lysosomal storage material.

Applications and implications of nanoceria reactivity: measurement tools and environmental impact

Cerium oxide nanoparticles or nanoceria have a unique structure and interesting and unusual redox and catalytic properties that vary with the size, shape, charge, surface coating and chemical reactivity. This paper highlights applications and environmental implications of nanoceria, and describes methodologies for the assessment of the reactivity and potential toxicological effects of these particles. The physical and chemical properties in the particle design that are responsible for their reactivity and transformation in environmental and biological conditions are described. Processes such as surface oxidation, formation of surface complexes and potential interaction with redox active components of the environment are discussed. An overview of analytical characterization methods for study of nanoceria properties, reactivity and impact, highlighting methodological challenges and limitations is presented. Examples discussed include strategies to determine physicochemical properties, cytotoxicity and antioxidant or pro-oxidant activity in various exposure environments. Development of new measurement tools to facilitate rapid assessment and accelerate screening of these particles for their reactivity and effects is discussed. Future research needs for environmental assessment of benefits and potential risks associated with the use of nanoceria are also provided.

Attaching DNA to Nanoceria: Regulating Oxidase Activity and Fluorescence Quenching

Cerium oxide nanoparticles (nanoceria) have recently emerged as a nanozyme with oxidase activity. In this work, we present a few important interfacial properties of nanoceria. First, the surface charge of nanoceria can be controlled not only by adjusting pH but also by adsorption of simple inorganic anions. Adsorption of phosphate and citrate gives negatively charged surface over a broad pH range. Second, nanoceria adsorbs DNA via the DNA phosphate backbone in a sequence-independent manner; DNA adsorption inhibits its oxidase activity. Other anionic polymers display much weaker inhibition effects. Adsorption of simple inorganic phosphate does not have the inhibition effect. Third, nanoceria is a quencher for many fluorophores. These discoveries provide an important understanding for further use of nanoceria in biosensor development, materials science, and nanotechnology.

Neuroprotective mechanisms of cerium oxide nanoparticles in a mouse hippocampal brain slice model of ischemia

Cerium oxide nanoparticles (nanoceria) are widely used as catalysts in industrial applications because of their potent free radical-scavenging properties. Given that free radicals play a prominent role in the pathology of many neurological diseases, we explored the use of nanoceria as a potential therapeutic agent for stroke. Using a mouse hippocampal brain slice model of cerebral ischemia, we show here that ceria nanoparticles reduce ischemic cell death by approximately 50%. The neuroprotective effects of nanoceria were due to a modest reduction in reactive oxygen species, in general, and ~ 15% reductions in the concentrations of superoxide (O 2 •−) and nitric oxide, specifically. Moreover, treatment with nanoceria markedly decreased (~ 70% reduction) the levels of ischemia-induced 3-nitrotyrosine, a modification to tyrosine residues in proteins induced by the peroxynitrite radical. These findings suggest that scavenging of peroxynitrite may be an important mechanism by which cerium oxide nanoparticles mitigate ischemic brain injury. Peroxynitrite plays a pivotal role in the dissemination of oxidative injury in biological tissues. Therefore, nanoceria may be useful as a therapeutic intervention to reduce oxidative and nitrosative damage after a stroke.

Nanoceria as antioxidant: Synthesis and biomedical applications

The therapeutic application of nanomaterials has been a focus of numerous studies in the past decade. Due to its unique redox properties, cerium oxide (ceria) is finding widespread use in the treatment of medical disorders caused by the reactive oxygen intermediates (ROI). The radical-scavenging role of ceria nanoparticles (nanoceria) have been established, as well as the autocatalytic ability of nanoceria to regenerate under various environmental conditions. The synthesis of nanoceria in biocompatible media has also been reported along with cell viability in order to determine the potential use of nanoceria in biomedical applications.