Effects Of Cerium Oxide Nanoparticles Research Articles

Radioprotective Effect of Cerium Oxide Nanoparticles Against Genotoxicity Induced by Ionizing Radiation on Human Lymphocytes.

Ionizing radiation induces DNA damage on normal cell results in apoptosis and cell deaths. The radioprotective effects of cerium oxide nanoparticles (CNPs) on genotoxicity, apoptosis and necrosis induced by Ionizing Radiation (IR) in human healthy lymphocytes as highly radiosensitive cells were investigated. Lymphocytes were prepared from three volunteers and then treated with CNPs at different concentrations and exposed to IR at dose 1.5 Gy. The radioprotective effects of CNPs were assessed by micronucleus (MN) assay and flow cytometry. Interleukin-1 was quantified in treated samples. It was found that CNPs reduced the percentage of MN induced by IR in lymphocytes up to 73%. CNPs treatment significantly reduced IR-induced apoptotic and necrotic incidences in human lymphocytes. CNPs significantly reduced IL-1β produced in cell environment exposed to IR. The present study demonstrated that CNPs may be an effective radioprotector against DNA damage and apoptosis induced by IR mainly through mitigation of pro-inflammatory process in lymphocytes. This result provides a new potential indication of CNPs for protection of normal cells during radiation therapy in the treatment of cancer or unwanted radiation exposure.

Elucidating the Effects of Cerium Oxide Nanoparticles and Zinc Oxide Nanoparticles on Arsenic Uptake and Speciation in Rice ( Oryza sativa) in a Hydroponic System.

The accumulation of arsenic (As) in rice grains depends greatly on the redox chemistry in rice rhizosphere. Intentional or accidental introduction of strong oxidizing or reducing agents, such as metallic engineered nanoparticles (ENPs) into the plant-soil ecosystem, can change As speciation and plant uptake. However, investigation on the effects of ENPs on plant uptake of co-occurring redox sensitive heavy metals and their speciation in plant tissues is scarce. We investigated the mutual effects of two commonly encountered ENPs, cerium oxide nanoparticles (CeO2 NPs) and zinc oxide nanoparticles (ZnO NPs), and two inorganic species of As on their uptake and accumulation in rice seedlings in a hydroponic system. Rice seedlings were exposed to different combinations of 1 mg/L of As(III) or As(V) and 100 mg/L of CeO2 NPs and ZnO NPs for 6 days about 40 days after germination. ZnO NPs significantly reduced the accumulation of As(III) in rice roots by 88.1 and 96.7% and in rice shoots by 71.4 and 77.4% when the initial As was supplied as As(III) and As(V), respectively. ZnO NPs also reduced As(V) in rice roots by 68.3 and 52.3% when the As was provided as As(III) and As(V), respectively. However, the As(V) in rice shoots was unaffected by ZnO NPs regardless of the initial oxidation state of As. Neither the total As nor the individual species of As in rice tissues was significantly changed by CeO2 NPs. The co-presence of As(III) and As(V) increased Ce in rice shoots by 6.5 and 2.3 times but did not affect plant uptake of Zn. The results confirmed the active interactions between ENPs and coexisting inorganic As species, and the extent of their interactions depends on the properties of ENPs as well as the initial oxidation state of As.

Biophysical, docking, and cellular studies on the effects of cerium oxide nanoparticles on blood components: in vitro.

IntroductionThe application of nanoparticles (NPs) in medicine and biology has received great interest due to their novel features. However, their adverse effects on the biological system are not well understood.Materials and methodsThis study aims to evaluate the effect of cerium oxide nanoparticles (CNPs) on conformational changes of human hemoglobin (HHb) and lymphocytes by different spectroscopic (intrinsic and synchronous fluorescence spectroscopy and far and near circular dichroism [CD] spectroscopy), docking and cellular (MTT and flow cytometry) investigations.Results and discussionTransmission electron microscopy (TEM) showed that CNP diameter is ~30 nm. The infrared spectrum demonstrated a strong band around 783 cm−1 corresponding to the CNP stretching bond. Fluorescence data revealed that the CNP is able to quench the intrinsic fluorescence of HHb through both dynamic and static quenching mechanisms. The binding constant (Kb), number of binding sites (n), and thermodynamic parameters over three different temperatures indicated that hydrophobic interactions might play a considerable role in the interaction of CNPs with HHb. Synchronous fluorescence spectroscopy indicated that microenvironmental changes around Trp and Tyr residues remain almost unchanged. CD studies displayed that the regular secondary structure of HHb had no significant changes; however, the quaternary structure of protein is subjected to marginal structural changes. Docking studies showed the larger CNP cluster is more oriented toward experimental data, compared with smaller counterparts. Cellular assays revealed that CNP, at high concentrations (>50 µg/mL), initiated an antiproliferative response through apoptosis induction on lymphocytes.ConclusionThe findings may exhibit that, although CNPs did not significantly perturb the native conformation of HHb, they can stimulate some cellular adverse effects at high concentrations that may limit the medicinal and biological application of CNPs. In other words, CNP application in biological systems should be done at low concentrations.

Effect of cerium oxide nanoparticles coating on the electrodes of benthic microbial fuel cell

ABSTRACTBenthic microbial fuel cell is a power source for low-power devices. For enhancement of power, Cerium oxide (CeO2) nanoparticles (NPs) were coated on anode and cathode electrodes and compared separately. CeO2 NPs were synthesized by hydrothermal method and characterized by Dynamic light scattering. Polyvinylidene fluoride and graphite powder were used as a conductive matrix for binding CeO2 NPs. Coated electrodes were characterized by physical and electrochemical analysis. Maximum power densities generated by CeO2 coated cathode and anode were 60 and 43 mW/m3 respectively; whereas conductive matrix only produced 14 mW/m3. Results demonstrated that CeO2 at cathode performed better than at anode. NPs show their effectiveness as an oxygen reduction reaction catalyst in the sea water.

Cerium oxide nanoparticles as potential antibiotic adjuvant. Effects of CeO2 nanoparticles on bacterial outer membrane permeability

BackgroundTherapeutic options against Multi Drug Resistant (MDR) pathogens are limited and the overall strategy would be the development of adjuvants able to enhance the activity of therapeutically available antibiotics. Non-specific outer membrane permeabilizer, like metal-oxide nanoparticles, can be used to increase the activity of antibiotics in drug-resistant pathogens. The study aims to investigate the effect of cerium oxide nanoparticles (CeO2 NPs) on bacterial outer membrane permeability and their application in increasing the antibacterial activity of antibiotics against MDR pathogens. MethodsThe ability of CeO2 NPs to permeabilize Gram-negative bacterial outer membrane was investigated by calcein-loaded liposomes. The extent of the damage was evaluated using lipid vesicles loaded with FITC-dextran probes. The effect on bacterial outer membrane was evaluated by measuring the coefficient of permeability at increasing concentrations of CeO2 NPs. The interaction between CeO2 NPs and beta-lactams was evaluated by chequerboard assay against a Klebsiella pneumoniae clinical isolate expressing high levels of resistance against those antibiotics. ResultsCalcein leakage increases as NPs concentrations increase while no leakage was observed in FITC-dextran loaded liposomes. In Escherichia coli the outer membrane permeability coefficient increases in presence of CeO2 NPs. The antibacterial activity of beta-lactam antibiotics against K. pneumoniae was enhanced when combined with NPs. ConclusionsCeO2 NPs increases the effectiveness of antimicrobials which activity is compromised by drug resistance mechanisms. The synergistic effect is the result of the interaction of NPs with the bacterial outer membrane. The low toxicity of CeO2 NPs makes them attractive as antibiotic adjuvants against MDR pathogens.

Shifts in N and δ15N in wheat and barley exposed to cerium oxide nanoparticles

The effects of cerium oxide nanoparticles (CeO2-NPs) on 15N/14N ratio (δ15N) in wheat and barley were investigated. Seedlings were exposed to 0 and 500 mg CeO2-NPs/L (Ce-0 and Ce-500, respectively) in hydroponic suspension supplied with NH4NO3, NH4+, or NO3−. N uptake and δ15N discrimination (i.e. differences in δ15N of plant and δ15N of N source) were measured. Results showed that N content and 15N abundance decreased in wheat but increased in barley, and Ce-500 only induced whole-plant δ15N discrimination (−1.48‰, P ≤ 0.10) with a simultaneous decrease (P ≤ 0.05) in whole-plant δ15N (−3.24‰) compared to Ce-0 (−2.74‰) in wheat in NH4+. Ce-500 decreased (P ≤ 0.01) root δ15N of wheat in NH4NO3 and NH4+ (3.23 and −2.25‰, respectively) compared to Ce-0 (4.96 and −1.27‰, respectively), but increased (P ≤ 0.05) root δ15N of wheat in NO3− (3.27‰) compared to Ce-0 (2.60‰). Synchrotron micro-XRF revealed the presence of CeO2 in shoots of wheat and barley regardless of N source. Although the longer-term consequences of CeO2-NP exposure on N uptake and metabolism are unknown, the results clearly show the potential for ENMs to interfere with plant metabolism of critical plant nutrients such as N even when toxicity is not observed.

Embryo-Protective Effects of Cerium Oxide Nanoparticles against Gestational Diabetes in Mice.

Gestational diabetes is defined as carbohydrate intolerance with onset or first recognition during pregnancy. Diabetes during pregnancy increases the incidences of congenital anomalies, in a mother and her embryo. Oxidative stress has been implicated to be responsible in diabetic embryopathy. In this study, we used nanoceria as an antioxidant for amelioration of diabetic embryopathy in diabetic mice. The female mice were divided into 5 groups (6 mice per group). Diabetes was induced by a single dose of streptozotocin (60 mg/kg IP) that dissolved in citrate buffer (pH = 4.6). Blood glucose was checked in 0,5,10, and 15 days of pregnancy. The diabetic state was confirmed when the blood glucose concentration exceeded 200 mg/dL. On the day 16 of pregnancy, all animals were anesthetized with ether and embryos were excised; then oxidative stress, pathological parameters, number of implantations, miscarriage, and live embryo were assayed. Histological study showed that diabetes induced abortion; decrease in weight of mothers, embryo, and the number of embryos were observed. In diabetic mice, significant increase in lipid peroxidation (LPO), ROS formation, and protein carbonyl content were observed. Glutathione (GSH) concentration is found to be decreased in embryo tissue in diabetic mice. Nanoceria treatment significantly inhibited embryonic oxidative stress and also pathologic changes in diabetic mice. Our research showed that diabetes act as a teratogen agent for fetal development and nanoceria abrogated diabetes induced embryopathy via its antioxidant effects. So, early detection of diabetes in pregnancy and antioxidant administration can attenuate these complications.

Quantitative Cytotoxicity, Cellular Uptake and Radioprotection Effect of Cerium Oxide Nanoparticles in MRC-5 Normal Cells and MCF-7 Cancerous Cells

Optimal distribution of cerium oxide nanoparticles (CONPs) or nanoceria can have a significant impact on their cytotoxicity, cellular uptake, and radioprotection effects. In this study, two different distribution plans of CONPs were investigated. A scanner electron microscope (SEM) was used for chemical analysis and recording of CONP images. Using MTT assay, the non-toxic concentrations of nanoceria with two different distribution plans were determined in MRC-5 and MCF-7 cell lines. Nanoceria cellular uptake at 50, 150, and 250 I¼M with two different dispersion plans was determined by using the UV/VIS absorbance of cell culture medium after 24 h of incubation. In order to quantify radioprotection effect, cells treated with non-toxic concentrations of nanoceria were exposed to 10, 40, and 100 cGy of 6 MV photon beams. The diameter of the spherical CONPs was 29 nm. Energy dispersive spectroscopy analysis showed that the cerium element has the highest weight percentage in CONPs (97.9). Accumulation rate of filtered and non-filtered suspension were determined as 0.3608 and 14.2708 I¼g/ml/h, respectively. The 70 and 110 I¼M concentration of sustained nanoceria suspension did not have any toxicity for MRC-5 and MCF-7 cells, respectively. In both cell lines, 50, 150, and 250 I¼M of filtered nanoceria had a significant uptake than the non-filtered nanoceria. A total of results showed that the 70 I¼M of nanoceria have a significant radioprotection on normal cells in the radiation dose of 40 and 100 cGy, while the highest cellular uptake of nanoceria occurred in cancer cells. The results suggest that using of stable distribution of CONPs for radiation protection could be a good choice, knowing that these nanostructures will have selective protection in normal cells. © 2018, Springer Science+Business Media, LLC, part of Springer Nature.

An experimental study on the thermal conductivity of cerium oxide/ethylene glycol nanofluid: developing a new correlation

The main aim of this experimental study is to examine the effect of cerium oxide nanoparticles on the thermal conductivity of ethylene glycol. In this way, cerium oxide nanoparticles with the particle diameter of 10–30 nm have been used for making nanofluid samples. The samples were made in volume concentration range of 0.25–2.5% using a two-step method. Visual observation of nanofluid samples showed that they have acceptable stability. Transient hot wire method was used for measuring the thermal conductivity of the samples. Measurements were done for all samples at temperatures ranging from 25to 50°C. Measurements showed that the thermal conductivity of nanofluid enhanced with increasing temperature and solid volume fraction. The results also showed that the thermal conductivity of ethylene glycol could enhance by about 22% when the nanoparticles volume fraction reaches 2.5%. This enhancement occurred at 50°C. Finally, a mathematical correlation was presented to predict the thermal conductivity ratio of CeO2/EG using curve-fitting. This correlation, a two-variable function of temperature and volume fraction, showed a linear relationship between thermal conductivity ratio and these variables.

Nephroprotective effect of cerium oxide nanoparticles on cyclophosphamide-induced nephrotoxicity via anti-apoptotic and antioxidant properties in BALB/c mice

Nephroprotective effect of cerium oxide nanoparticles on cyclophosphamide-induced nephrotoxicity via anti-apoptotic and antioxidant properties in BALB/c mice

Protective effect of cerium oxide nanoparticle on sperm quality and oxidative damage in malathion-induced testicular toxicity in rats: An experimental study

Malathion is an organophosphorus pesticide that commonly used in many agricultural and non-agricultural processes. Previous studies have reported the effects of melatonin on the reproductive system. Cerium dioxide nanoparticles (CeNPs) due to their antioxidative properties are promising to impact on the development of male infertility. The aim of this study was to evaluate the effect of CeNPs on oxidative stress and sperm parameters after malathion exposure of male rats. 36 adult male Wistar rats were divided into 6 groups (n=6/each): Control, CeNPs -treated control (15 and 30 mg/kg/day), malathion (100 mg/ kg/day), and CeNPs -treated malathion groups (15 and 30 mg/ kg/day). At the end of the study (4 wk), the sperm counts, motility, and viability in the testis of rats were measured, also lipid peroxidation, total antioxidant capacity, and total thiol groups in homogenate testis were investigated. Malathion significantly reduced sperm count, viability, and motility than the control rats (p<0.001). Co-treatment of malathion with CeNPs 30 mg/kg had a protective effect on sperm counts (p=0.03), motility (p=0.01), and viability (p<0.001) compare to malathion group. Also, the results showed that malathion reduced testis total anti-oxidant capacity, the total thiol group, and increased testis malondialdehyde than the control rats (p<0.001). CeNPs 30 mg/kg are increased total antioxidant capacity (p<0.001) and total thiol group (p=0.03) compared to malathion group. CeNPs at both doses (15 and 30 mg/kg) improved malondialdehyde than the malathion group (p<0.001 and p=0.01 respectively). CeNPs 30 mg/kg administered considerably restored testicular changes induced by malathion. The improvement of oxidative stress by CeNPs may be associated with increased sperm counts, motility and viability in the testis.

Analysis of the antioxidant enzyme‐mimetic activity and neuroprotective effects of cerium oxide nanoparticles stabilized with varying ratios of citric acid and EDTA

Cerium oxide (CeO2) nanoparticles (nanoceria or CeNPs) are potent antioxidants that are being explored as a potential therapeutic for diseases featuring oxidative stress. However, both beneficial and toxic effects of CeNPs have been reported. We hypothesize that the method of synthesis as well as the choice of stabilizers coating the particles can lead to disparate biological effects. In the present study we tested the antioxidant enzyme‐mimetic properties of a series of custom‐synthesized CeNPs that differed in the citric acid (CA) and EDTA ratio (CA:EDTA) used to stabilize them. We first spun each type of CeNP at 100,000 RPM (434,513 xg) in order to separate it into supernatant (SUP) and pellet (PEL) fractions. We then used commercially available enzymatic assay kits to assess the catalase‐ and superoxide dismutase (SOD)‐mimetic activity of each fraction. The CeNPs stabilized with only CA (CA:EDTA ratio of 100:0) exhibited significantly higher catalase‐mimetic activity in both the SUP and PEL fractions compared to the other samples. Varying the CA:EDTA ratio had opposing effects in the SOD‐mimetic activity of the SUP and PEL fractions. For example, CeNPs stabilized with only CA (CA:EDTA ratio of 100:0 ) displayed most of the SOD‐mimetic activity in the PEL. In contrast, CeNPs stabilized with only EDTA (CA:EDTA ratio of 0:100) showed highest level of SOD‐mimetic activity in the SUP. Intermediate ratios (CA:EDTA of 40:60) showed intermediate levels of SOD‐mimetic activity in the SUP and PEL fractions. We then tested the effects of these CeNPs in a mouse hippocampal brain slice model of ischemia where cell death was assessed using the fluorescence indicator SYTOX green. Interestingly, no significant neuroprotection was observed in brain slices treated with CeNPs stabilized with the extreme ratios of CA:EDTA (100:0 and 0:100). However, slices treated with CeNPs stabilized with intermediate ratios of CA:EDTA (50:50, 40:60, 30:70) showed significantly reduced ischemic cell death. When the SUP and PEL fractions of the CA:EDTA 50:50 sample were tested separately, only the slices treated with the pellet fraction showed significantly reduced cell death. These results demonstrate that CeNPs varying in the ratio of CA:EDTA used for stabilization display different enzyme‐mimetic activity. More importantly, our data suggest that CeNPs synthesized with intermediate CA:EDTA stabilization ratios demonstrate the best neuroprotection profile in ischemic brain slices and that the neuroprotective activity resides in the PEL fraction of the CeNPs.Support or Funding InformationThis work was supported by St. Lawrence University and Cerion Advanced Materials.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Cardioprotective effect of cerium oxide nanoparticles in monocrotaline rat model of pulmonary hypertension: A possible implication of endothelin-1

AimsCerium oxide nanoparticles (CeO2NPs) have been recently introduced into the medical field for their antioxidant properties. The ability of CeO2NPs alone or in combination with spironolactone (SP) to attenuate monocrotaline (MCT)-induced pulmonary hypertension and associated right ventricular hypertrophy was studied in rats. A special emphasis was given to endothelin-1 pathway. Materials and methodsPulmonary hypertension was induced in albino rats by a single subcutaneous injection of MCT (60 mg/kg). Rats received either single CeO2NPs therapy or combined therapy with SP for 2 weeks. Key findingsCeO2NPs improved pulmonary function tests with concomitant decrease in serum endothelin-1 and pulmonary expression of endothelin-1 and its receptor ETAR. Besides, CeO2NPs diminished MCT-induced right ventricular hypertrophy and reduced cardiac oxidative stress and apoptosis. SignificanceCeO2NPs could improve pulmonary hypertension and associated right ventricular hypertrophy with no additive value for SP. Besides being an antioxidant, CeO2NPs work through endothelin-1 pathway to improve pulmonary hypertension.

Role of cerium oxide nanoparticle-induced autophagy as a safeguard to exogenous H2O2-mediated DNA damage in tobacco BY-2 cells.

The effect of cerium oxide nanoparticle (CeNP) in plants has elicited substantial controversy. While some investigators have reported that CeNP possesses antioxidant properties, others observed CeNP to induce reactive oxygen species (ROS). In spite of considerable research carried out on the effects of CeNP in metazoans, fundamental studies that can unveil its intracellular consequences linking ROS production, autophagy and DNA damage are lacking in plants. To elucidate the impact of CeNP within plant cells, tobacco BY-2 cells were treated with 10, 50 and 250 µg ml-1 CeNP (Ce10, Ce50 and Ce250), for 24 h. Results demonstrated concentration-dependent accumulation of Ca2+ and ROS at all CeNP treatment sets. However, significant DNA damage and alteration in antioxidant defence systems were noted prominently at Ce50 and Ce250. Moreover, Ce50 and Ce250 induced DNA damage, analysed by comet assay and DNA diffusion experiments, complied with the concomitant increase in ROS. Furthermore, to evaluate the antioxidant property of CeNP, treated cells were washed after 24 h (to minimise CeNP interference) and challenged with H2O2 for 3 h. Ce10 did not induce genotoxicity and H2O2 exposure to Ce10-treated cells showed lesser DNA breakage than cells treated with H2O2 only. Interestingly, Ce10 provided better protection over N-acetyl-L-cysteine against exogenous H2O2 in BY-2 cells. CeNP exposure to transgenic BY-2 cells expressing GFP-Atg8 fusion protein exhibited formation of autophagosomes at Ce10. Application of vacuolar protease inhibitor E-64c and fluorescent basic dye acridine orange, further demonstrated accumulation of particulate matters in the vacuole and occurrence of acidic compartments, the autophagolysosomes, respectively. BY-2 cells co-treated with CeNP and autophagy inhibitor 3-methyladenine exhibited increased DNA damage in Ce10 and cell death at all assessed treatment sets. Thus, current results substantiate an alternative autophagy-mediated, antioxidant and geno-protective role of CeNP, which will aid in deciphering novel phenomena of plant-nanoparticle interaction at cellular level.

Effects of cerium oxide nanoparticles on differentiated/undifferentiated human intestinal Caco-2 cells

Since ingestion constitute one of the main routes of nanoparticles (NPs) exposure, intestinal cells seems to be a suitable choice to evaluate their potential harmful effects. Caco-2 cells, derived from a human colon adenocarcinoma, have the ability to differentiate forming consistent cell monolayer structures. For these reasons Caco-2 cells, both in their undifferentiated or differentiated state, are extendedly used. We have used well-structured monolayers of differentiated Caco-2 cells, as a model of intestinal barrier, to evaluate potential harmful effects associated to CeO2NPs exposure via ingestion. Different parameters such as cell toxicity, monolayer integrity and permeability, cell internalization, translocation through the monolayer, and induction of DNA damage were evaluated. No toxic effects of CeO2NPs were observed, independently of the differentiated state of the Caco-2 cells. In the same way, no effects on the monolayer integrity/permeability were observed. Although important cell uptake was demonstrated in undifferentiated cells (by using confocal microscopy), CeO2NPs remained mostly attached to the apical membrane in the differentiated cells. In spite of this apparent lack of uptake in differentiated cells, translocation of CeO2NPs to the basolateral chamber was observed by using confocal microscopy. Finally no genotoxic effects were observed when the comet assay was used, although decreases in the levels of oxidized bases were observed, supporting the antioxidant role of CeO2NPs.

Antiamyloid Activity of Functionalized Cerium Oxide Nanoparticle on Lysozyme Fibrillation: Spectroscopic and Microscopic Investigation

Accumulation of amyloid fibrils of proteins in different organs is a pathological indication for various neurogenerative disorders. Recently nanotechnology is at the centre of interest to tackle with those disorders. In this study we have chosen hen egg white lysozyme as our model protein which is responsible for hereditary systemic Amyloidosis disease. Here we have reported effect of Cerium oxide nanoparticle (CeONP), folic acid functionalized CeONP (FA-CeONP) and polyacrylic acid functionalized CeONP (PAA-CeONP) (all of them having size ~18 nm) on fibrillation of hen egg white lysozyme (Lyz). The amyloid growth is monitored by Thioflavin T (ThT), Congo Red (CR), 8-anilinonapthalene-1-sulfonic acid (ANS) assay, time resolved fluorescence anisotropy, intrinsic fluorescence, circular dichroism, atomic force microscopy and fluorescence microscopy study. Results demonstrate that all nanoparticle (NP) shows antiamyloid activity by broadening lag phase and suppressing growth phase of Lyz amyloid growth, but PAA-CeONP shows maximum inhibitory effect. These bare and functionalized CeONP shows dose dependent antiamyloid activity. We have also demonstrated that such inhibition of amyloid formation is associated with reduction of s-sheet content of protein. The inhibition efficiency is quantified by half maximal inhibition concentration IC50 values. A mechanistic pathway is explained on the basis of electrostatic interaction between NP and Lyz by ζ- potential measurement. This interaction is also analyzed theoretically by docking analysis. Thus our study provides a basis for use of CeONP as a promising candidate in therapeutic application in amyloid related disorders.

Fabrication of Cerium Oxide Nanoparticles by Solution Combustion Synthesis and Their Cytotoxicity Evaluation

The diverse abilities such as the antioxidant effect of cerium oxide nanoparticles (CeO2-NPs) have encouraged researchers to pursue CeO2-NPs as a therapeutic agent to treat a number of diseases, including cancer and diabetes. The synthesis method of CeO2-NPs affected on its abilities. In this study, nanosize ceria powders were synthesized by combustion of aqueous containing corresponding cerium nitrate, ammonium nitrate, and glycine redox mixtures. Solution combustion synthesis is a fast and cost-efficient process with high purity product. The crystallite structures were characterized by various methods, including X-ray diffraction technique, high-resolution scanning electron microscopy, transmission electron microscopy, and UV–vis spectroscopy technique. The combustion was flaming and yields voluminous oxides with nano size (20–30 nm). In addition, no diffraction patterns that are characteristic of impurities were observed, indicating the purity of the CeO2-NPs. In vitro cytotoxicity studies on L929 cells, a non-toxic effect in all concentration (up to 1000 μg/mL) was indicated and it can be believed that this nanoparticle will have viable applications in different medical fields.

Experimental analysis of the effects of cerium oxide nanoparticles on a single-cylinder diesel engine using biofuel blended with diesel as fuel

ABSTRACTEnergy demand is the hot topic of all developing and developed countries. Energy demand has been increasing day by day at a high rate. So, it is necessary to find an alternative solution that is eco-friendly. Biodiesel can be the alternative solution for this problem. The main purpose of this paper is to test the engine performance and emission parameters of a diesel engine using pure cinnamon oil blended with diesel and using cerium oxide as a catalyst. The parameters measured are brake power, brake thermal efficiency, specific fuel conception, CO2, CO, NOx and HC.

Corrigendum: Intrinsic and Extrinsic Properties Affecting Innate Immune Responses to Nanoparticles: The Case of Cerium Oxide.

[This corrects the article on p. 970 in vol. 8, PMID: 28855907.].

Human hemoglobin adsorption onto colloidal cerium oxide nanoparticles: a new model based on zeta potential and spectroscopy measurements

The nanoparticle (NP)-induced conformational changes of protein and NP agglomeration have gained a remarkable interest in medical and biotechnological fields. Herein, the effect of human hemoglobin (Hb) on the colloidal stability of cerium oxide NP (CNP) was investigated by dynamic light scattering (DLS), zeta potential, and TEM analysis. In addition, the effect of CNP on the heme degradation and structural changes of Hb was studied using fluorescence, circular dichroism (CD), and UV–visible (UV–vis) spectroscopic methods. DLS and TEM analysis showed that the presence of Hb can increase the mean diameter of CNP. Zeta potential measurements revealed that CNP demonstrated a higher charge distribution relative to CNP/Hb complex. Besides, fluorescence studies indicated that two fluorescent heme degradation products are revealed during the interaction of CNP with Hb. Near UV-CD spectroscopy also showed that the microenvironmental changes of heme groups occur after interaction of Hb with CNP. The result of thermal behavior of Hb confirmed the structural changes of protein, which referred to decrease in the Hb stability in the presence of CNP. Indeed, the finding related to structural and functional changes of Hb induced by CNP may be crucial to obtain information regarding the side effects of NPs. Finally, this data reveal much insight into the effects of the interaction on protein structural changes and NP agglomeration, and can correlate the zeta potential of NP-protein complexes with the nature of the principle NP-protein interaction.