Synthesis, physico-chemical characterization, and antioxidant effect of PEGylated cerium oxide nanoparticles


Cerium oxide nanoparticles (CNPs) represent a promising class of antioxidant nanoparticles with potential therapeutic value. Due to the easily reversible oxidation states of cerium (Ce3+ and Ce4+) at the nanoscale, CNPs scavenge excessive reactive oxygen and nitrogen species in a self-regenerative manner. In this study, we have demonstrated a simple method to functionalize shape-specific CNPs (i.e., rod- and cube-shaped) with polyethylene glycol (PEG) and studied the effect of PEGylation on the physico-chemical properties, antioxidant activity, and biocompatibility of rod- and cube-shaped CNPs. The chemical conjugation of PEG onto the CNP surface was confirmed by a series of physico-chemical characterizations (1H-NMR, FTIR, and surface zeta potential). Rod-shaped CNPs demonstrated greater reactive oxygen species scavenging ability compared to cube-shaped CNPs. PEGylation of CNPs did not affect shape, cerium oxidation state, and cytocompatibility. Importantly, PEGylation significantly reduced the amount of proteins adsorbed onto the CNPs. The antioxidant effects of CNPs were maintained in PEGylated CNPs. We envision that PEGylated rod-shaped CNPs synthesized in this study have the potential to be biocompatible nanoparticles that can combat oxidative stress-related diseases.

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We acknowledge funding support from the School of Pharmacy, University of Pittsburgh (SS). YX and AP acknowledge the Graduate Student Research Scholarship from the School of Pharmacy, University of Pittsburgh. We thank Dr. Donna Stolz, Center for Biologic Imaging, University of Pittsburgh, for access to the TEM facility. We thank Dr. Paul Johnston, School of Pharmacy, University of Pittsburgh, for access to the spectrophotometer. We thank Piyusha Sane and Michael Washington, University of Pittsburgh, for critical reading of the manuscript.

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Correspondence to Shilpa Sant.

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Xue, Y., Balmuri, S.R., Patel, A. et al. Synthesis, physico-chemical characterization, and antioxidant effect of PEGylated cerium oxide nanoparticles. Drug Deliv. and Transl. Res. 8, 357–367 (2018).

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  • Polyethylene glycol (PEG)
  • PEGylated cerium oxide nanoparticle
  • Antioxidant
  • Reactive oxygen species (ROS)
  • Shape-specific cerium oxide nanoparticles