Comparative Structural and Optical Properties of Different Ceria Nanoparticles

Herein a comparative study of five nanocrystalline cerium oxides (CeO2-delta) synthesised by different methods and calcined at 500 degrees C is reported. XRPD analysis showed that stoichiometry parameter delta, crystallite size/strain and lattice constant were only slightly affected by the method utilized. All ceria nanoparticles are nearly spherical in shape with faceted morphology, free of defects and with a relatively uniform size distribution. The average microstrain was found to be approximately 10 times higher than that of bulk counterpart. The absorption edge of nanocrystalline materials was shifted towards a higher wavelengths (red shift) in comparison with bulk counterpart, and band gap values were in the range 2.7-3.24 eV (3.33 eV for bulk counterpart)

Supplementary data for article: Antic, B.; Boskovic, M.; Nikodinovic-Runic, J.; Ming, Y.; Zhang, H.; Bozin, E. S.; Janković, D.; Spasojevic, V.; Vranjes-Djuric, S. Complementary Approaches for the Evaluation of Biocompatibility of 90Y-Labeled Superparamagnetic Citric Acid (Fe,Er)3O4 Coated Nanoparticles. Materials Science and Engineering C 2017, 75, 157–164. https://doi.org/10.1016/j.msec.2017.02.023

Supplementary material for: [https://doi.org/10.1016/j.msec.2017.02.023]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2453]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3086

Supplementary data for article: Antic, B.; Boskovic, M.; Nikodinovic-Runic, J.; Ming, Y.; Zhang, H.; Bozin, E. S.; Janković, D.; Spasojevic, V.; Vranjes-Djuric, S. Complementary Approaches for the Evaluation of Biocompatibility of 90Y-Labeled Superparamagnetic Citric Acid (Fe,Er)3O4 Coated Nanoparticles. Materials Science and Engineering C 2017, 75, 157–164. https://doi.org/10.1016/j.msec.2017.02.023

Supplementary material for: [https://doi.org/10.1016/j.msec.2017.02.023]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2453]Related to accepted version: [http://cherry.chem.bg.ac.rs/handle/123456789/3086

Magnetite/Mn-ferrite nanocomposite with improved magnetic properties

Magnetic nanocomposites can show enhanced properties compared to their single phase counterparts. Novel soft ferrite Fe3O4/soft ferrite MnFe2O4 nanocomposite, as well as pure MnFe2O4 and Fe3O4 for the sake of comparison, were synthesized by co-precipitation method. The spinel type of structure (space group Fd (3) over barm) of the samples was confirmed by XRPD and SAED. Samples are composed of spherical particles with size in the range 5-15 nm. Nanocomposite (92 wt%) MnFe2O4/(8 wt%) Fe3O4 exert single phase like magnetic behavior. Saturation magnetization (M-S) of Fe3O4/MnFe2O4 is 26% greater than M-S of MnFe2O4 and even 50% than M-S of Fe3O4. At the same time coercivity field of the nanocomposite is twice less value (H-C=180 Oe) than in binary ferrites (H-C=360 Oe). Magnetization enhancement and softening in Magnetite/Mn-ferrite is discussed related to particle interactions among two different ferrites and intrinsic properties of nanoparticles. Tailoring phase ratio and synthesis conditions can be a tool for tuning magnetic properties of nanocomposites. (C) 2014 Elsevier B.V. All rights reserved

Effects of Eu3+ Concentration on Structural, Optical and Vibrational Properties of Multifunctional Ce1-X,EuXO2-delta Nanoparticles Synthesized by Thermolysis of 2,4-Pentanedione Complexes

The 5-10 nnn Ce1-XEuXO2-delta (0 lt = x lt = 0.30) nanoparticles with fluorite structure were synthesized by thermal decomposition of Eu- and Ce-2,4-pentanedione complexes mixtures. X-ray line broadening analysis of mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) showed that the crystallite size was lower and root mean square strain higher than in pure ceria. However, within mixed samples Ce1-XEuXO2-delta (0.05 lt = x lt = 0.30) crystallite size and root mean square strain were independent of Eu3+ concentration. Raman spectroscopy results indicated that europium ions yield disorder by breaking the phonon propagation and therefore making the non-centre Brillouin zone modes Raman active. The absorption bands in the spectra of mixed oxides were blue-shifted in comparison to pure CeO2-delta nanopowder. The samples show red emission typical for Eu ions. The biggest photoluminescent intensity was observed for the highest Eu3+ concentration (x = 0.30) and further enhanced with the increase in crystallinity

Complementary approaches for the evaluation of biocompatibility of Y-90-labeled superparamagnetic citric acid (Fe,Er)(3)O-4 coated nanoparticles

Magnetic nanoparticles (MNPs) are of immense interest for diagnostic and therapeutic applications in medicine. Design and development of new iron oxide-based MNPs for such applications is of rather limited breadth without reliable and sensitive methods to determine their levels in body tissues. Commonly used methods, such as ICP, are quite problematic, due to the inability to decipher the origin of the detected iron, i.e. whether it originates from the MNPs or endogenous from tissues and bodily fluids. One of the approaches to overcome this problem and to increase reliability of tracing MNPs is to partially substitute iron ions in the MNPs with Er. Here, we report on the development of citric add coated (Fe,Er)(3)O-4 nanopartides and characterization of their physico-chemical and biological properties by utilization of various complementary approaches. The synthesized MNPs had a narrow (6-7 nm) size distribution, as consistently seen in atomic pair distribution function, transmission electron microscopy, and DC magnetization measurements. The particles were found to be superparamagnetic, with a pronounced maximum in measured zero-field cooled magnetization at around 90 K. Reduction in saturation magnetization due to incorporation of 1.7% Er3+ into the Fe3O4 matrix was clearly observed. From the biological standpoint, citric acid coated (Fe,Er)(3)O-4 NPs were found to induce low toxicity both in human cell fibroblasts and in zebrafish (Danio rerio) embryos. Biodistribution pattern of the MNPs after intravenous administration in healthy Wistar rats was followed by the radiotracer method, revealing that Y-90-labeled MNPs were predominantly found in liver (7533% ID), followed by lungs (16.70% ID) and spleen (2.83% ID). Quantitative agreement with these observations was obtained by ICP-MS elemental analysis using Er as the detected tracer. Based on the favorable physical, chemical and biological characteristics, citric add coated (Fe,Er)(3)O-4 MNPs could be further considered for the potential application as a diagnostic and/or therapeutic agent. This work also demonstrates that combined application of these techniques is a promising tool for studies of pharmacokinetics of the new MNPs in complex biological systems.Peer-reviewed manuscript: [https://imagine.imgge.bg.ac.rs/handle/123456789/1763]Supplementary data: [https://imagine.imgge.bg.ac.rs/handle/123456789/1764