Fluoride-assisted detection of glutathione by surface Ce3+/Ce4+ engineered nanoceria
Patel V. Jose L. Philippot G. Aymonier C. Inerbaev T. McCourt L.R. Ruppert M.G. Qi D. Li W. Qu J. Zheng R. Cairney J. Yi J. Vinu A. Karakoti A.S.
4 November 2022Royal Society of Chemistry
Journal of Materials Chemistry B
2022#10Issue 479855 - 9868 pp.
Nanoceria has evolved as a promising nanomaterial due to its unique enzyme-like properties, including excellent oxidase mimetic activity, which significantly increases in the presence of fluoride ions. However, this significant increase in oxidase activity has never been utilised as a signal enhancer for the detection of biological analytes partly because of the lack of understanding of the mechanism involved in this process. In this study, we show that the surface oxidation state of cerium ions plays a very crucial role in different enzymatic activities, especially the oxidase mimetic activity by engineering nanoceria with three different surface Ce4+/Ce3+ compositions. Using DFT calculations combined with Bader charge analysis, it is demonstrated that stoichiometric ceria registers a higher oxidase mimetic activity than oxygen-deficient ceria with a low Ce4+/Ce3+ ratio due to a higher charge transfer from a substrate, 3,3′,5,5′ tetramethylbenzidine (TMB), to the ceria surface. We also show that the fluoride ions can significantly increase the charge transfer from the TMB surface to ceria irrespective of the surface Ce4+/Ce3+ ratio. Using this knowledge, we first compare the fluoride sensing properties of nanoceria with high Ce4+ and mixed Ce4+/Ce3+ oxidation states and further demonstrate that the linear detection range of fluoride ions can be extended to 1-10 ppm for nanoceria with mixed oxidation states. Then, we also demonstrate an assay for fluoride assisted detection of glutathione, an antioxidant with elevated levels during cancer, using nanoceria with a high surface Ce4+/Ce3+ ratio. The addition of fluoride ions in this assay allows the detection of glutathione in the linear range of 2.5-50 ppm with a limit of detection (LOD) of 3.8 ppm. These studies not only underpin the role of the surface Ce4+/Ce3+ ratio in tuning the fluoride assisted boost in the oxidase mimetic activity of nanoceria but also its strategic application in designing better colourimetric assays.
Text of the article Перейти на текст статьи
Global Innovative Center for Advanced Nanomaterials (GICAN), School of Engineering College of Engineering, Science and Environment, The University of Newcastle, Callaghan, 2308, NSW, Australia
Univ. Bordeaux, CNRS, Bordeaux INP, ICMCB, UMR 5026, Pessac, F-33600, France
L. N. Gumilyov Eurasian National University, Nur-Sultan, 010008, Kazakhstan
National University of Science and Technology “MISIS”, Moscow, 119049, Russian Federation
School of Engineering, College of Engineering, Science and Environment, The University of Newcastle, Callaghan, 2308, Australia
Centre for Materials Science, School of Chemistry and Physics, Queensland University of Technology, Brisbane, 4001, QLD, Australia
School of Physics, The University of Sydney, 2000, NSW, Australia
Global Innovative Center for Advanced Nanomaterials (GICAN)
Univ. Bordeaux
L. N. Gumilyov Eurasian National University
National University of Science and Technology “MISIS”
School of Engineering
Centre for Materials Science
School of Physics
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026