CeO2-Co3O4 nanocomposite with oxidase-like activity for colorimetric detection of ascorbic acid.
RSC Adv
; 13(15): 9918-9923, 2023 Mar 27.
Article
en En
| MEDLINE
| ID: mdl-36998518
A CeO2-Co3O4 nanocomposite (NC) was prepared and characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction. The obtained CeO2-Co3O4 NC displayed biomimicking oxidase-like activity, which can catalytically oxidize the 3, 3', 5, 5'-tetramethylbenzidine (TMB) substrate from colorless to the blue oxidized TMB (ox-TMB) product with a characteristic absorption peak at 652 nm. When ascorbic acid (AA) was present, ox-TMB would be reduced, resulting in a lighter blue and lower absorbance. On the basis of these facts, a simple colorimetric method for detection of AA was established with a linear relationship ranging from 1.0 to 500 µM and a detection limit of 0.25 µM. When this method was used to detect AA in human serum and commercially available vitamin C tablet samples, a good recovery of 92.0% to 109.0% was obtained. Besides, the catalytic oxidation mechanism was investigated, and the possible catalytic mechanism of CeO2-Co3O4 NC can be described as follows. TMB is adsorbed on the CeO2-Co3O4 NC surface and provides lone-pair electrons to the CeO2-Co3O4 NC, leading to an increase in electron density of the CeO2-Co3O4 NC. An increased electron density can improve the electron transfer rate between TMB and the oxygen absorbed on its surface to generate O2Ë- and ËO2, which further oxidize TMB.
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1
Colección:
01-internacional
Base de datos:
MEDLINE
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
RSC Adv
Año:
2023
Tipo del documento:
Article
Pais de publicación:
Reino Unido