Experimental and Theoretical Study of Morphological and Charging Properties of Truncated Octahedron and Cubic Ceria Nanoparticles: Implications for Biomedical Applications

Abstract

Ceria (CeO2) nanoparticles are known to be very often used in various applications from biomedicine to fuel cells. To optimize the applications, detailed information about the physicochemical properties such as size, shape, and charge of nanoparticles should be available. Therefore, in our study we performed a systematic study of ceria nanoparticles ranging from synthesis to comprehensive experimental and theoretical characterization. We synthesized ceria nanoparticles using two synthesis paths which led to the formation of two types of ceria nanoparticles. The structure and charging properties of both types of ceria nanoparticles were studied by using X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), particle charge detector (PCD) for surface charge density, and a ZetaPlus instrument for electrophoretic mobility measurements. The results suggested that in the case where hydrolysis of Ce­(NO3)3 at room temperature was applied nanoparticles with morphology close to a spherical, more exactly truncated octahedron were synthesized. On the other hand, nanoparticles obtained by hydrothermal synthesis had characteristic cube-like morphology. Finally, for more complete understanding and interpretation of the studied system, we prepared a theoretical model based on the classical density functional theory for electrolyte solutions coupled with the surface charge regulation via the law of mass action. Even without using fitting parameters, the theory adequately describes the experimental data. All the results obtained in our study could serve as a basis for obtaining tuned and engineered ceria nanoparticles with optimized physicochemical properties which could lead to the improved applications of the nanotechnology in the biomedical research.

Engineering of Oxygen-Deficient Nano-CeO2–x with Tunable Biocidal and Antioxidant Activity

“…We observe that FSP-made ox-CeO 2 is characterized by PZC = 4.8, lower than the typical values (∼6.0−6.5) reported in the literature for nanoceria materials. 31 On the other hand, oxygen-deficient nanoceria materials are characterized by higher PZC values (5.9−7.3). ζ-Potential and PZC, which define the particle charge at the shear plane, are pertinent to the particle/ biointerface and thus their acute toxicity profile.…”

Rational synthesis of gold-ceria catalysts supported on reduced graphene oxide with remarkable activity for CO oxidation

“…Ceria (CeO 2 ) is remarkable and versatile rare Earth oxide that has received immense attention both in academia and industry [14,15]. With major advancements over the past years, ceria nanoparticles (CeO 2 NPs) constituted a ubiquitous and attractive class of oxide nanomaterial with applications in numerous technological fields such as fuel cells [16], UV-blocking and anticorrosion coatings [17], biomedicine [18], chemical sensing [19], and heterogeneous catalysis [20,21]. CeO 2 is considered effective catalyst support because of its unique redox properties and oxygen storage capacity; that is the ability to exchange between Ce(IV) and Ce(III) oxidation states with structural integrity [22].…”

β-Cyclodextrin Stabilized Nanoceria for Hydrolytic Cleavage of Paraoxon in Aqueous and Cationic Micellar Media

“…The organophosphatase activity of β-CD@CeO 2 NPs was explored by studying the kinetics of hydrolysis of paraoxon in aqueous and micellar media of the cationic surfactants (cetyltrimethylammonium bromide, dodecyltrimethylammonium bromide, trimethyl-n-tetradecylammonium bromide, cetylpyridinium chloride). Above the physiological pH, β-CD@CeO 2 NPs showed negative charges on the surface, which is suitable for the various nucleophilic substitution reactions. The pH of the reaction medium also affects the micellar concentration of surfactant. , Therefore, the kinetic investigation of hydrolytic cleavage of the O–P bond of organophosphorus pesticides (paraoxon) has been studied considering the nucleophility of β-CDs@CeO 2 NPs in aqueous and cationic micellar media.…”