Activity Of CeO2 Nanoparticles Research Articles

The H2O2 Self-Sufficient 3D Printed β-TCP Scaffolds with Synergistic Anti-Tumor Effect and Reinforced Osseointegration.

Tumor recurrence and massive bone defects are two critical challenges for postoperative treatment of oral and maxillofacial tumor, posing serious threats to the health of patients. Herein, in order to eliminate residual tumor cells and promote osteogenesis simultaneously, the hydrogen peroxide (H2O2) self-sufficient TCP-PDA-CaO2-CeO2 (TPCC) scaffolds are designed by preparing CaO2 or/and CeO2 nanoparticles (NPs)/chitosan solution and modifying the NPs into polydopamine (PDA)-modified 3D printed TCP scaffolds by rotary coating method. CaO2 NPs loaded on the scaffolds can release Ca2+ and sufficient H2O2 in the acidic tumor microenvironment (TME). The generated H2O2 can further produce hydroxyl radicals (·OH) under catalysis effect by peroxidase (POD) activity of CeO2 NPs, in which the photothermal effect of the PDA coating enhances its POD catalytic effect. Overall, NPs loaded on the scaffold chemically achieve a cascade reaction of H2O2 self-sufficiency and ·OH production, while functionally achieving synergistic effects on anti-tumor and bone promotion. In vitro and in vivo studies show that the scaffolds exhibit effective osteo-inductivity, induced osteoblast differentiation and promote osseointegration. Therefore, the multifunctional composite scaffolds not only validate the concept of chemo-dynamic therapy (CDT) cascade therapy, but also provide a promising clinical strategy for postoperative treatment of oral and maxillofacial tumor.

Emission characteristics study of compression ignition engine fuelled with biodiesel and cerium oxide nanoparticle blends

This work investigates the detailed study on emission characteristics of compression ignition engine fuelled with diesel, mahua oil biodiesel (MOBD) and cerium oxide nanoparticle (CeO2). Cerium oxide nanoparticles were mixed with neat mahua oil methyl ester (MOME) at a different dose of 100 and 200 ppm on a mass basis. Experimental results revealed that nanoparticle had a positive effect on emissions of MOME. CeO2 nanoparticle acts as an oxygen shelter owing to its high surface energy content due to its huge surface to volume ratio that expedites the process of combustion. Among the fuels containing CeO2 nanoparticles, MOBDCeO2200 showed an improvement in various emissions as compared to conventional fuels. CeO2 nanoparticles were the superior oxidising catalysts as they could effectively reduce HC and CO emissions. NO x emission reduced substantially due to catalytic activity of CeO2 nanoparticles.

Effects of oxygen vacancy and sintering temperature on the photoluminescence properties and photocatalytic activity of CeO2 nanoparticles with high uniformity

Gamma-ray irradiation assisted polyacrylamide gel route was applied to synthesize the homogeneous CeO2 nanoparticles. XRD results and optical properties indicates that the vacancy concentration and the energy gap (Eg) value of CeO2 nanoparticles increases with the increasing crystallite size. Photoluminescence experiment indicates that a small number of –CH and –CH2, and C–O functional groups in presence of the CeO2 nanoparticles can help improve the photoluminescence properties of CeO2 nanoparticles. Photocatalytic experiment results indicate that the pure CeO2 nanoparticles exhibits an obviously enhanced photocatalytic activity due to its have higher vacancy concentration. The dye concentration of 5 mg L−1 and the catalyst concentration of 1 g L−1 were fixed for photocatalytic degradation of methylene blue (MB) dye. In addition, the CeO2 nanoparticles containing –CH and –CH2, and C–O functional groups exhibits an outstanding adsorption capacity, however, it is not advantageous to the photo-degradation of MB dye. Based on the experimental results, a possible photocatalytic mechanism for organic decorated the CeO2 nanoparticles are discussed.

Sonochemical-assisted synthesis and characterization of CeO2 nanoparticles and its photocatalytic properties

In the present study, cerium oxide (CeO2) nanoparticles were prepared through sonochemical-assisted method, using (NH4)2Ce(NO3)6, hydrazine and ethylenediamine as precursors. Also, the effects of concentration of precursors as well as reaction time on the morphology and size of nanoparticles were investigated. The synthesized CeO2 nanoparticles were characterized by X-ray diffraction patterns, energy-dispersive X-ray spectroscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and diffuse reflectance spectroscopy. The results indicate that the estimated particle size of synthesized CeO2 nanoparticles is about 20–30 nm. Furthermore, photocatalytic activities of CeO2 nanoparticles were investigated by degradation of methylene blue under UV-light irradiation.