The characterization of purified citrate-coated cerium oxide nanoparticles prepared via hydrothermal synthesis

Matthew L. Hancock, Robert A. Yokel, Matthew J. Beck, Julie L. Calahan, Travis W. Jarrells, Eric J. Munson, George A. Olaniyan, Eric A. Grulke

Research output: Contribution to journalArticlepeer-review

25 Scopus citations

Abstract

Hypothesis: Cerium oxide nanoparticles were synthesized using a hydrothermal approach with citric acid as a stabilizing agent. Citric acid adsorption onto the nanoceria particle surface can cease particle formation and create a stable dispersion for an extended shelf life. The product was dialyzed immediately following the synthesis to remove unreacted cerium that could contribute to biological effects. Nanoparticle characterization results are expected to help identify the surface citrate bonding structure. Experiments: Many characterization techniques were utilized to determine size, morphology, surface properties, and citrate complexation on the nanoceria particle surface. These included transmission electron microscopy, electron energy loss spectroscopy, dynamic light scattering, x-ray diffraction, thermogravimetric analysis, Fourier-transform infrared spectroscopy, Raman spectroscopy, UV–Vis absorption spectroscopy, zeta potential, and 13C solid-state nuclear magnetic resonance spectroscopy. Findings: Primary particles were hexagonal, determined to be 4.2 nm in diameter. The hydrodynamic diameter of the dialyzed product was 10.8 nm. Each agglomerate was estimated to contain an average of 5.7 particles. The citrate coating contained 2.8 citrate molecules/nm2, corresponding to an approximate citrate monolayer. Citrate complexation with the nanoceria surface includes the central carboxyl geminal to the hydroxyl and perhaps one of its terminal carboxyl groups.

Original languageEnglish
Article number147681
JournalApplied Surface Science
Volume535
DOIs
StatePublished - Jan 1 2021

Bibliographical note

Funding Information:
This work is funded by the National Institutes of Health under Award Number R01GM109195 . The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health . E.J. Munson is a partial owner of Kansas Analytical Services, a company that provides solid-state NMR services to the pharmaceutical industry. The results presented here are from academic work at the University of Kentucky and no data from Kansas Analytical Services is presented here. The authors acknowledge support from Dali Qian (TEM), Nancy Miller (XRD), Freddy Arce (Raman), Andrew Colburn (Zeta potential), and Landon Mott (UV-Vis). The authors would also like to thank Marsha Ensor for her contribution.

Funding Information:
This work is funded by the National Institutes of Health under Award Number R01GM109195. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. E.J. Munson is a partial owner of Kansas Analytical Services, a company that provides solid-state NMR services to the pharmaceutical industry. The results presented here are from academic work at the University of Kentucky and no data from Kansas Analytical Services is presented here. The authors acknowledge support from Dali Qian (TEM), Nancy Miller (XRD), Freddy Arce (Raman), Andrew Colburn (Zeta potential), and Landon Mott (UV-Vis). The authors would also like to thank Marsha Ensor for her contribution.

Publisher Copyright:
© 2020 Elsevier B.V.

Keywords

  • Ceria-citrate complexation
  • Characterization results
  • Citrate-coating
  • Dialysis
  • Hydrothermal synthesis
  • Nanoceria

ASJC Scopus subject areas

  • Chemistry (all)
  • Condensed Matter Physics
  • Physics and Astronomy (all)
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films

Fingerprint

Dive into the research topics of 'The characterization of purified citrate-coated cerium oxide nanoparticles prepared via hydrothermal synthesis'. Together they form a unique fingerprint.

Cite this