CeO2 Nanoparticles Research Articles

Impact of nano cerium oxide addition with pyrolysis waste plastic oil on combustion, performance and emission characteristics of CRDI diesel engine

Abstract This investigation examined the effect of incorporating cerium oxide (CeO2) nanoparticle into diesel and waste plastic oil (WPO) blends on the combustion, performance and emission characteristics of the diesel engine. The WPO was extracted from low density polyethylene using plastic pyrolysis. The blending of diesel and WPO with combination of D70:WPO30 and D50:WPO50 was prepared to evaluate the engine operation. Additionally, the spherical sized CeO2 with 50 mg/L and 100 mg/L was added with this blend. The various blends named as Diesel, D-WPO30, D-WPO30+Ce50, D-WPO30+Ce100, D-WPO50, D-WPO50+Ce50 and D-WPO50+Ce100 were used in this investigation to operate the engine under various load conditions. The experiment was performed using water cooled common rail direct injection (CRDI) diesel engine with prepared D-WPO blend. Different characteristics such as In-cylinder pressure (CP), heat release rate (HRR), ignition delay time (IDT), brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and exhaust gas temperature (EGT), carbon monoxide (CO), hydrocarbon (HC), nitrogen oxide (NOx) and smoke opacity emission are studied with respect to the effect of different blends and applied load used. It was observed that increasing of CeO2 nanoparticles in blend improved the overall performance and emission of the engine. Form the results, D-WPO30+Ce100 blend showed enhanced brake thermal efficiency (BTE), brake specific fuel consumption (BSFC) and exhaust has temperature (EGT) are 28.2%, 3% and 465oC respectively. Similarly, reduced emission of CO, NOx, HC and smoke opacity was observed in the CeO2 added blends particularly at 100 mg/L. It was concluded that among all blends prepared, the D70:WPO30 with 100 mg/L of CeO2 showed improved combustion, performance and emission characteristics in proposed diesel engine.

Cerium Oxide‐Armored Composite Latex Particles by Visible Light Emulsion Photopolymerization: From Synthesis to Film Properties

AbstractCerium dioxide (CeO2) has huge potential in many applications ranging from biochemical engineering to the coating industry. Here, the first example of visible light photo‐mediated Pickering emulsion polymerization of (meth)acrylate monomers is reported using CeO2 nanoparticles (NPs) as solid stabilizer. A ω,ω′−dicarboxylic acid diphenyl disulfide photoinitiator is anchored on the surface of the CeO2 NPs and used to initiate the emulsion polymerization of methyl methacrylate (MMA) and of MMA/n‐butyl acrylate (MMA/BA) under visible light leading to CeO2‐armored latexes. Radicals generated upon light irradiation trigger the formation of polymer chains chemically attached to the CeO2 NPs, promoting their subsequent adsorption on the latex surface. The composite films obtained from the CeO2‐armored P(MMA‐co‐BA) latexes exhibit a unique honeycomb nanostructure with the nanoceria located in the walls giving the materials excellent mechanical, anti‐UV, and photocatalytic properties.

Enhanced Electrochemical Performance of Highly Porous CeO2-Doped Zr Nanoparticles for Supercapacitor Applications.

The aim of this work was to develop an ultrasonic-assisted synthesis method for the fabrication of CeO2-doped Zr nanoparticles that would improve the performance of supercapacitor electrodes. This method, which eliminates the need for high-temperature calcination, involves embedding CeO2 into Zr nanoparticles through 1 hr (CeO2-Zr-1) and 2 hrs (CeO2-Zr-2) of ultrasonic irradiation, resulting in the formation of nanostructures with significant improvements in their electrochemical properties. Through physicochemical analysis, we observed that the CeO2-doped Zr nanoparticles, particularly those treated for 2 hrs (CeO2-Zr-2), exhibit superior crystalline phase purity, optimal chemical surface composition, minimal agglomeration with particle sizes below 50 nm, and an impressive average surface area of 178 m2/g. Compared to the 1 hr irradiation samples (CeO2-Zr-1) and undoped CeO2 nanoparticles, the (CeO2-Zr-2) electrodes demonstrated a remarkable capacitance of 198 Fg-1 at a current density of 1 A/g while maintaining ~94.9% of their capacity after 3750 cycles. This indicates not only good reversibility but also exceptional stability. In (CeO2-Zr-2) samples, the nanospherical structure achieved through ultrasonic synthesis is responsible for the enhanced capacitive behavior and stability, along with the synergistic effects caused by Zr doping, which improves the CeO2 nanoparticle conductivity to a significant extent. Surface areas of the electrodes are larger due to the combination of these two materials, which contribute to their superior performance.

Composite Scaffold Materials of Nanocerium Oxide Doped with Allograft Bone: Dual Optimization Based on Anti-Inflammatory Properties and Promotion of Osteogenic Mineralization.

Spinal fusion technique is widely used in the treatment of lumbar degeneration, cervical instability, disc injury, and spinal deformity. However, it is usually accompanied by a high incidence of fusion failure and pseudoarthrosis, placing higher demands on bone implants. Therefore, materials with good biocompatibility, osteoconductivity, and even induce bone ingrowth, which can be used to improve spinal fusion rate and bone regeneration, have become a hot research topic. Here, ultra-small cerium oxide nanoparticles (CeO2 NPs) are prepared and loaded onto the surface of the homograft bone surface to prepare a composite scaffold AB@PLGA/CeO2. The composite scaffold shows the competitive ability to promote osteoblast differentiation in vitro. In vivo experiments show that AB@PLGA/CeO2 has a good bone enhancement effect. In particular, good biological effects of collagen fiber formation, osteogenic mineralization, and tissue repair are shown in intervertebral implant fusion. Further, transcriptome sequencing confirms that CeO2 NPs promote osteogenic differentiation and mineralization by regulating extracellular matrix (ECM) and collagen formation. Meanwhile, CeO2 NPs can regulate the function of the PI3K-Akt signaling pathway to exert its ability to promote osteogenic differentiation and mineralization and affect p53 and cell cycle signaling pathway to regulate osteogenic differentiation and mineralization. Hence, the proposed scaffold is a promising strategy for intervertebral fusion in the clinic.

Effect of oxygen vacancies on enhancing the photo-catalytic activity, photo-luminescence and electronic structure properties of nanostructured Y-doped CeO2

The exceptional characteristics of CeO2 and Ce1-xYxO2 (x = 0.03, 0.05 and 0.07) nanoparticles were reported in the manuscript supporting that Y3+replaces Ce3+/Ce4+leads to oxygen vacancies formation. The results of XRD measurements revealed FCC structure of decreased crystallite size of CeO2 with improved crystallinity. To investigate the surface morphology, HRTEM and SAED patterns were performed. EDX analyses were undertaken to discuss the elemental and compositional characteristics. The absorption spectra using UV–Vis–NIR spectroscopy were analyzed and red shifted absorbance was found to enhance with decreasing band gap values for increased Y doping. The Photoluminescence spectra depicted various emissions representing the development of various defects and oxygen vacancy with incorporation of Y content in the lattice with CCT values below 4000 K to be classified as warm yellow light for indoor applications. The development of oxygen vacancies in the CeO2 lattice was further supported by XPS measurements for core levels Ce 3d, O 1s and Y 3d. Furthermore, the XPS measurements also reported the valence states of elements, Ce with 3+ and 4+, Y with 3+ and O with 2- along with charged oxygen vacancies. The photo-catalytic analysis revealed that Y-doped CeO2 nanoparticles show better degradation using a variety of characterization. A degradation mechanism that illustrates the impact of oxygen vacancies created by Y-doping on the photo-degradation process has been proposed. The novelty of Y-doped CeO2 nanoparticles stems from their improved photo-catalytic activities, which are linked to structural changes and the formation of oxygen vacancies. This doping considerably affects the electrical structure, resulting in better light absorption and less electron-hole recombination. The detailed outcomes of present study suggested the use of Y-doped CeO2 nanoparticles in optoelectronics, spintronics devices and photo-catalyst applications.

Retraction Note: ROS-mediated cytotoxic activity of ZnO and CeO2 nanoparticles synthesized using the Rubia cordifolia L. leaf extract on MG-63 human osteosarcoma cell lines.

Retraction Note: ROS-mediated cytotoxic activity of ZnO and CeO2 nanoparticles synthesized using the Rubia cordifolia L. leaf extract on MG-63 human osteosarcoma cell lines.

Metal–Organic Framework-Derived CeO2/Gold Nanospheres in a Highly Sensitive Electrochemical Sensor for Uric Acid Quantification in Milk

In this work, CeBTC (a cerium(III) 1,3,5-benzene-tricarboxylate), was used as a precursor for obtaining CeO2 nanoparticles (nanoceria) with better sensor performances than CeO2 nanoparticles synthesized by the solvothermal method. Metal–organic framework-derived nanoceria (MOFdNC) were functionalized with spheric gold nanoparticles (AuNPs) to further improve non-enzymatic electrode material for highly sensitive detection of prominent biocompound uric acid (UA) at this modified carbon paste electrode (MOFdNC/AuNPs&CPE). X-ray powder diffraction (XRPD) and transmission electron microscopy (TEM) analysis were used for morphological structure characterization of the obtained nanostructures. Cyclic voltammetry and electrochemical impedance spectroscopy, both in an [Fe(CN)6]3−/4− redox system and uric acid standard solutions, were used for the characterization of material electrocatalytic performances, the selection of optimal electrode modifier, and the estimation of nature and kinetic parameters of the electrode process. Square-wave voltammetry (SWV) was chosen, and the optimal parameters of technique and experimental conditions were established for determining uric acid over MOFdNC/AuNPs&CPE. Together with the development of the sensor, the detection procedure was optimized with the following analytical parameters: linear operating ranges of 0.05 to 1 µM and 1 to 50 µM and a detection limit of 0.011 µM, with outstanding repeatability, reproducibility, and stability of the sensor surface. Anti-interference experiments yielded a stable and nearly unchanged current response with negligible or no change in peak potential. After minor sample pretreatment, the proposed electrode was successfully applied for the quantification of UA in milk.

Unexpected nanoscale CeO2 structural transformations induced by ecologically relevant phosphate species

In the present study, the dissolution and microstructural transformation of CeO2 nanoparticles (NPs) in a phosphate-containing milieu were investigated. The dissolution behaviour of 2 nm and 5 nm CeO2 NPs in phosphate buffer solutions was found to differ markedly from that observed in 0.01 M NaClO4. Through synchrotron X-ray diffraction analysis and X-ray absorption spectroscopy, the interaction between CeO2 NPs and phosphate species was examined, revealing the transformation of the oxide into sodium-cerium double phosphate, with cerium predominantly existing in the Ce(IV) state. According to scanning and transmission electron microscopy observations, thus formed Na-Ce(IV) phosphate consists of spindle-like aggregates of nanocrystalline rods, presumably formed during phosphate anions sorption on the initial CeO2 surface. Pair distribution function analysis revealed that Na-Ce(IV) phosphate has a three-dimensional framework crystal structure, similar to NaTh2(PO4)3, as reported earlier, with large channels along the c-axis containing disordered sodium atoms. This study represents the first detailed analysis of phosphate-induced speciation and microstructural transformation of CeO2 NPs, resulting in the formation of Ce(IV) phosphate. Similar processes may occur in natural ecosystems upon the introduction of CeO2 NPs.

Synthesis and characterization of CeO2 nanoparticles using Plectranthus barbatus leaf extract and its CO gas sensing and antimicrobial activity

In this study, we synthesized cerium oxide nanoparticles (CeO2 NPs) using Plectranthus barbatus leaf extract. Characterization via X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and UV–visible spectroscopy revealed a bandgap of 2.98 eV. XRD confirmed their crystalline nature, while HRTEM showed cubic fluorite structures with an average particle size of 11.23 nm. The CeO2 NPs exhibited antibacterial properties against both gram-positive and gram-negative bacteria and high sensitivity to carbon monoxide (CO) at 100 °C, especially at low concentrations. This research highlights the low environmental impact and potential applications of CeO2 NPs in gas sensing and antibacterial contexts.

Improving UV protection and retention of photosensitive agrochemicals: Innovative polyurethane-CeO2 hybrid pesticide microcapsules

Photolysis and poor retention significantly decrease the utilization efficiency of photosensitive agrochemicals, leading to considerable ecological and economic losses. We successfully prepared novel pyraclostrobin-loaded polyurethane-inorganic hybrid microcapsules (Pyr@KCeO2-PU MCs) with high adhesion and UV stability by interfacial polymerization. CeO2 nanoparticles (NPs) were incorporated as UV light absorbers, while a silane coupling agent (KH550) was employed for in situ crosslinking of PU with CeO2 NPs, facilitating their dispersion within the PU shell. Characterization results revealed a high encapsulation efficiency of 90 % and uniform sizes (D50 = 915 nm) for the Pyr@KCeO2-PU MCs. Optical property investigations using UV–vis spectroscopy indicated that the integration of CeO2 NPs within the PU shell produced stronger UV absorption bands compared to both Pyr technical (TC) and Pyr@PU MCs. This observation underscores the potential of CeO2 NPs as effective UV absorbers. The anti-photolysis performance of Pyr@KCeO2-PU MCs improved with the addition of CeO2 NPs, yielding a retention rate of Pyr in Pyr@KCeO2-PU MCs that was 1.90 and 1.27 times greater than that of Pyr TC and Pyr@PU MCs, respectively, under UV irradiation. Furthermore, KH550 not only facilitated crosslinking between PU and CeO2 NPs, ensuring uniform distribution of CeO2 NPs on the PU shell surface, but also enhanced wettability and foliar retention. The contact angle of Pyr@KCeO2-PU MCs (32°) was significantly lower than that of Pyr@PU MCs (84°), and Pyr retention on rice leaves was 17.5 mg/cm2 for Pyr@KCeO2-PU MCs, surpassing that of Pyr@PU MCs (9.3 mg/cm2). Additionally, Pyr@KCeO2-PU MCs exhibited superior efficacy against various plant pathogens compared to Pyr TC and Seltima. These findings highlight the potential of Pyr@KCeO2-PU MCs for enhancing pesticide utilization and offer valuable insights for the future development of PU-based pesticide formulations.

Multifunctional CeO2:Fe3+ electrodes: Superior uric acid sensing and high-efficiency supercapacitor application

This study investigates the versatile capabilities of iron-doped CeO2-modified carbon paste electrodes (FCO MCPE) for both enhanced uric acid (UA) detection and efficient energy storage applications. Iron-doped CeO2 nanoparticles were synthesized via combustion synthesis. Cyclic voltammetry (CV) showed a 29 % increase in anodic peak current (2.05 µA) with the FCO MCPE compared to bare carbon paste electrodes (BCPE) (1.59 µA), indicating improved catalytic properties. Analysis of scan rates revealed a diffusion-controlled oxidation process. Differential pulse voltammetry (DPV) demonstrated excellent linearity (R2 = 0.999) and low detection limits (LOD: 0.132 µM, LOQ: 0.442 µM). Selectivity tests confirmed the superior ability of the FCO MCPE to differentiate UA from dopamine (DA), with a high linearity (R2 = 0.998). Stability tests showed only an 11 % decrease in performance after 15 cycles. In super capacitor evaluations, FCO materials exhibited a high specific capacitance of 200.43 F g−1 at 2 mV/s and impressive cycling stability with 87.5 % capacitance retention after 5000 cycles. Electrochemical impedance spectroscopy (EIS) revealed efficient charge transfer with a peak specific capacitance of 52.39 F g−1 at 0.01 Hz. These findings underscore the potential of FCO MCPEs for both effective UA detection and efficient super capacitor applications.

Non-Invasive Ultra-Sensitive Detection of Breast Cancer Biomarker using Cerium Nanoparticle Functionalized Graphene Oxide enabled Impedimetric Aptasensor

Epidermal growth factor receptor (EGFR) is a transmembrane protein and a key biomarker implicated in the pathogenesis of breast cancer. Early and precise detection of EGFR is crucial for effective diagnosis, prognosis, and therapeutic intervention. However, conventional EGFR detection techniques, such as biopsy and immunohistochemistry, are often invasive, time-consuming, and limited in sensitivity, highlighting the demand for non-invasive, highly sensitive detection methods. In this study, we fabricated a cerium oxide (CeO₂) and graphene oxide (GO) nanocomposite-based aptasensor for the non-invasive detection of EGFR using electrochemical impedance spectroscopy (EIS). The CeO₂-GO nanocomposite was synthesized via the sol-gel method and characterized through UV-Vis spectroscopy, FTIR, TEM, and XRD, confirming the crystalline structure of hexagonal CeO₂ nanoparticles on amorphous GO sheets. The nanocomposite was functionalized with aptamers specific to EGFR using covalent coupling reactions. The EIS analysis of the fabricated aptasensor (GCE/CeO₂-GO/EGFR-Apt/BSA) demonstrated a wide linear detection range from 10 fg mL-1 to 100 ng mL-1, with an ultralow detection limit of 1.87 fg mL-1 in PBS, 3.16 fg mL-1 in serum, 5.31 fg mL-1 in sweat, and 6.14 fg mL-1 in saliva samples. These results highlight the aptasensor’s high sensitivity, specificity, and potential for real-time, non-invasive EGFR monitoring in clinical samples such as serum, sweat, and saliva. This approach would facilitate early detection of cancer and personalized diagnostics in point-of-care settings.

Effect of surfactants with different ionizing properties on dispersion stability and PCMP properties of CeO2 nanoparticle polishing slurry

Effect of surfactants with different ionizing properties on dispersion stability and PCMP properties of CeO2 nanoparticle polishing slurry

Faсile synthesis of vase-like CeO2 microcapsules and their ordered arrays using the technique of spraying Ce(NO3)3 solution microdroplets on the alkali solution surface

In this work, it has been demonstrated for the first time that CeO2 microcapsules with a unique vase-like morphology can be produced using a facile technique of spraying microdroplets of an aqueous Ce(NO3)3 solution onto the alkaline solution surface of Na2SO4. It has been shown that layers of these microcapsules can be transferred from the solution surface to the substrate surface in two different ways, and depending on the transfer method, they can form ordered, oriented arrays on the substrate. A peculiarity of one of these arrays is that in the layer on the substrate surface, almost all of the microcapsules are oriented with the hole in the wall toward the substrate, while in the other type of array they are oriented in the opposite direction. The structural and chemical characteristics of these microcapsules were investigated using SEM, STEM, HRTEM, EDX, XRD, UV-Vis DR, Raman and FT-IR spectroscopy. It has been established that the walls of these microcapsules are approximately 50-100 nm thick and consist of CeO2 nanocrystals with a size of 2-5 nm with fcc crystal structure of fluorite. On the surface of these nanocrystals, there are adsorbed NO3- and SO42- anions that can be removed by heating the samples to temperatures of 400°C and 600°C, respectively. The use of a solution containing a mixture of Ce(III) and Eu(III) nitrates as a reagent in the synthesis process allows for the production of microcapsules whose walls consist of CeO2 nanocrystals that were doped with Eu(III) cations. These microcapsules exhibit photoluminescent properties in the visible region of the spectrum with maximum band intensities at λex = 330 nm and 462 nm. It is proposed that this technique for synthesizing microcapsules could be used to produce microcapsules based on CeO2 nanoparticles doped with a wide range of metal cations.

The Ce-modified biochar for efficient removal of methylene blue dye: Kinetics, isotherms and reusability studies

Exploring modification methods for enhancing the adsorption performance of biochar-based adsorbents for effective removal of methylene blue (MB), biochar-loaded CeO2 nanoparticles (Ce/BC) were synthesized by pomelo peels through co-precipitation combined with the pyrolysis method. Ce/BC showed a higher specific surface area and disorder degree than that of BC. The 0.5Ce/BC (mass ratio of Ce(NO3)3·6H2O/BC=0.5/1) showed the best performance to adsorption of MB solution at different reaction conditions (MB concentration, Ce/BC composites dosage, and initial pH). Adsorption kinetics and equilibrium isotherms were well-described with a pseudo-first-order equation and Langmuir model, respectively. In addition, the maximum adsorption capacity of 0.5Ce/BC for MB was 105.68 mg·g−1 at 328 K. The strong adsorption was attributed to multi-interactions including pore filling, π-π interactions, electrostatic interaction, and hydrogen bonding between the composites and MB. This work demonstrated that the modified pomelo peels biochar, as a green promising material with cost-effectiveness, exhibited a great potential for broad application prospectively to dyeing-contaminated wastewater treatment.

Development and Characterization of Advanced Nano-Coating with CeO₂, Al₂O₃, ZnO, and TiO₂ Nanoparticles for Enhanced Durability and Corrosion Resistance

This study introduces an innovative sol-gel nano-coating designed to address silica scaling and corrosion in hydrothermal and high-stimulation environments. By incorporating CeO₂, Al₂O₃, ZnO, and TiO₂ nanoparticles into a polymer matrix through precise sonication techniques, the coating achieves uniform dispersion and enhanced functional performance. The meticulous characterization of nanoparticle integration optimizes mechanical strength, thermal stability, and chemical resistance. Applied via a directional supplying device, the nano-coating is mechanically deposited onto the cemented walls of wells, providing robust protection against scaling and corrosion across diverse conditions, including varying temperatures and pH levels. Laboratory testing demonstrates significant reductions in silica scaling and corrosion rates, confirming the coating's efficacy in maintaining production efficiency in both hydrothermal projects and fracking operations. This paper details the synthesis process and molecular chemistry involved in nanoparticle integration, alongside the resultant structural properties of the coating. Thermogravimetric analysis (TGA) assesses thermal stability, while kinetic models such as Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) evaluate activation energy without assuming specific reaction models. The findings highlight the potential of this advanced nano-coating as a robust solution for enhancing operational longevity and efficiency in challenging industrial applications.

Anticancer Activity of Green Synthesized Manganese Doped Cerium Oxide Nanoparticles Prepared by Using Acacia Concinna Fruit Extract

AbstractPure CeO2 and Ce1‐xMnxO2, where x = 0, 2, 4 and 6% w/w, were synthesized by sol‐gel method using Acacia Concinna fruit extract as a surfactant and stabilizing agent. The synthesized particles were subjected to various characterization techniques, including XRD, HRTEM, FESEM, FTIR, Raman and UV‐Visible spectroscopy. The XRD pattern of the samples demonstrated single phase of CeO2, with cubic fluorite type structure and crystallite size of 6–7 nm. The morphology of the nanoparticles (NPs) was analyzed by FESEM and HRTEM which illustrated an aggregate of irregular spherical nanoparticles and the average particle size is around 18 nm. Raman spectroscopy validated the phase purity and indicated about the structural defects caused by the dopants. The bandgap energy of CeO2 NPs is calculated to be 3.00 eV from the Tauc plot of UV‐Visible spectroscopy, which gradually decreased to 2.43 eV with increase in manganese doping. Cytotoxicity studies signified the role of Mn‐doped CeO2 NPs as a potential nanotherapeutic agent for cancer treatment. The cell viability assay showed that 200 µg/mL of 6% Mn‐doped CeO2 nanoparticles exhibited remarkable cytotoxic effect by inhibiting 50% of cancer cells both in breast and colon cancer cell lines without affecting the healthy cell lines.

Morphophysiological, biochemical, and nutrient response of spinach (Spinacia oleracea L.) by foliar CeO2 nanoparticles under elevated CO2

Nanomaterials offer considerable benefits in improving plant growth and nutritional status owing to their inherent stability, and efficiency in essential nutrient absorption and delivery. Cerium oxide nanoparticles (CeO2 NPs) at optimum concentration could significantly influence plant morpho-physiology and nutritional status. However, it remains unclear how elevated CO2 and CeO2 NPs interactively affect plant growth and quality. Accordingly, the ultimate goal was to reveal whether CeO2 NPs could alter the impact of elevated CO2 on the nutrient composition of spinach. For this purpose, spinach plant morpho-physiological, biochemical traits, and nutritional contents were evaluated. Spinach was exposed to different foliar concentrations of CeO2 NPs (0, 25, 50, 100 mg/L) in open-top chambers (400 and 600 CO2 μmol/mol). Results showed that elevated CO2 enhanced spinach growth by increasing photosynthetic pigments, as evidenced by a higher photosynthetic rate (Pn). However, the maximum growth and photosynthetic pigments were observed at the highest concentration of CeO2 NPs (100 mg/L) under elevated CO2. Elevated CO2 resulted in a decreased stomatal conductance (gs) and transpiration rate (Tr), whereas CeO2 NPs enhanced these parameters. No significant changes were observed in any of the measured biochemical parameters due to increased levels of CO2. However, an increase in antioxidant enzymes, particularly in catalase (CAT; 14.37%) and ascorbate peroxidase (APX; 10.66%) activities, was observed in high CeO2 NPs (100 mg/L) treatment under elevated CO2 levels. Regarding plant nutrient content, elevated CO2 significantly decreases spinach roots and leaves macro and micronutrients as compared to ambient CO2 levels. CeO2 NPs, in a dose-dependent manner, with the highest increase observed in 100 mg/L CeO2 NPs treatment and increased roots and shoots magnesium (211.62–215.49%), iron (256.68–322.77%), zinc (225.89–181.49%), copper (21.99–138.09%), potassium (121.46–138.89%), calcium (118.22–91.32%), manganese (133.15–195.02%) under elevated CO2. Overall, CeO2 NPs improved spinach growth and biomass and reverted the adverse effects of elevated CO2 on its nutritional quality. These findings indicated that CeO2 NPs could be used as an effective approach to increase vegetable growth and nutritional values to ensure food security under future climatic conditions.

Development of Technology for the Synthesis of Nanocrystalline Cerium Oxide Under Production Conditions with the Best Regenerative Activity and Biocompatibility for Further Creation of Wound-Healing Agents

Background/Objectives: The issue of effective wound healing remains highly relevant. The objective of the study is to develop an optimal method for the synthesis of nanosized cerium oxide powder obtained via the thermal decomposition of cerium carbonate precipitated from aqueous nitrate solution for the technical creation of new drugs in production conditions; the select modification of synthesis under different conditions based on the evaluation of the physicochemical characteristics of the obtained material and its biological activity, and an evaluation of the broad-spectrum effect on cells involved in the regeneration of skin structure as well as antimicrobial properties. Methods: Several modes of the industrial synthesis of cerium dioxide nanoparticles (NPs) were carried out. The synthesis stages and the chemical and physical parameters of the obtained NPs were described using transmission electron microscopy (TEM), X-ray diffraction, Raman spectroscopy, and mass spectrometry. The cell cultures of human fibroblasts and keratinocytes were cultured with different concentrations of different nanoceria variations, and the cytotoxicity and the metabolic and proliferative activity were investigated. An MTT test and cell counting were performed. The antimicrobial activity of CeO2 variations at a concentration of 0.1–0.0001 M against Pseudomonas aeruginosa was studied. Results: The purity of the synthesized nanoceria powders in all the batches was >99.99%. According to TEM data, the size of the NPs varied from 1 nm to 70 nm under different conditions and methodologies. The most optimal technology for the synthesis of the nanoceria with the maximum biological effect was selected. A method for obtaining the most bioactive NPs of optimal size (up to 10 nm) was proposed. The repeatability of the results of the proposed method of nanoceria synthesis in terms of particle size was confirmed. It was proven that the more structural defects on the surface of the CeO2 crystal lattice, the higher the efficiency of the NPs due to oxygen vacancies. The strain provided the best redox activity and antioxidant properties of the nanoceria, which was demonstrated by better regenerative potential on various cell lines. The beneficial effect of synthesized nanoceria on the proliferative and metabolic activity of the cell lines involved in skin regeneration (human fibroblasts, human keratinocytes) was demonstrated. The antimicrobial effect of synthesized nanoceria on the culture of the most-resistant-to-modern-antibiotics microorganism Pseudomonas aeruginosa was confirmed. The optimal concentrations of the nanoceria to achieve the maximum biological effect were determined (10−3 M). Conclusions: It was possible to develop a method for the industrial synthesis of nanoceria, which can be used to produce drugs and medical devices containing CeO2 NPs.

Facile fabrication of redox nanoparticles loaded with exosomal-miRNAs and resveratrol as glycation inhibitor in alleviating the progression and development of diabetic cataract.

Diabetic cataract (DC) represents a highly prevalent ocular manifestation resulting from diabetes often culminating in vision impairment among individuals with diabetes. Regrettably, the armamentarium of pharmaceutical interventions capable of both delaying and thwarting the onset of DC remains conspicuously sparse. Based on contemporary investigations, the pathogenesis of DC is prominently influenced by oxidative harm to the crystalline lens and the nonenzymatic glycosylation of lens proteins. Consequently, we have developed self-regenerating cerium oxide nanoparticles (CeO2 NPs), enveloped with resveratrol (RSV) and exosomal-microRNA (miRNA) to alleviate the effects of DC in an in vitro model. Moreover, the inclusion of RSV within CeO2 NPs serves a dual purpose. It can act as an antioxidant, minimizing glycation, and induce oxidative stress by effectively neutralizing reactive oxygen species (ROS). Additionally, it serves as a glycation inhibitor effectively preventing the cross-linking. Consequently, it helps minimize the glucose level in hemoglobin and inhibits the formation of advanced glycation end products (AGEs). Likewise, the CeO2-exosomal-miRNA when treated alone found to slightly impede the viability of human lens epithelial cells (HLEC) and induce apoptosis by suppressing the expression of α-crystalline gene (CRYAA). Particularly, miRNAs target genes associated with oxidative stress pathways, protein glycation, and the generation of AGEs, hence preventing structural damage to lens proteins. Compared with CeO2, RSV-CeO2, and miRNA-RSV-CeO2, the presence of miRNA-RSV-CeO2 led to a significant decrease in hemoglobin glycation. Remarkably, miRNA-RSV-CeO2 NPs attenuate the formation of malondialdehyde (MDA) and conjugated dienes (CD) with a relative value of 14.63 and 11.37nmol/mg. As per the report, this method presents a promising opportunity to implement the proposed material combination for attenuating diabetic cataracts.