A novel “On-Off” colorimetric sensor for ascorbic acid and hydrogen peroxide based on peroxidase activity of CeO2/Co3O4 hollow nanocubes

• Published in: Journal of molecular structure 2024-04, Vol.1302, p.137507, Article 137507
• Main Authors: Zhang, Wenzhi, Lan, Yuxin, Chai, Dong-Feng, Lv, Jun, Dong, Guohua, Guo, Dongxuan
• Format: Article
• Language: English
• Subjects: Ascorbic acid; CeO2; Co3O4; Hydrogen peroxide; Peroxidase
• ISSN: 0022-2860
• DOI: 10.1016/j.molstruc.2024.137507

•The CeO2/Co3O4 hollow nanocubes with exceptional peroxidase-like activity have been successfully constructed.•The charge rearrangement at the heterointerface enhances the catalytic activity of nanozymes.•The hollow structure offers rich active sites available for enzymatic reactions.•This work establishes an effortless, cost-effective, and highly efficient "On-Off" colorimetric sensor for H2O2 and ascorbic acid. The development of artificial nanostructured enzymes has garnered significant interest in the field of nanobiotechnology due to the distinct advantages. In this work, CeO2/Co3O4 hollow nanocubes (named as CeO2/Co3O4 HNs) with exceptional peroxidase-like activity have been prepared employing ion exchange and subsequent calcination process. In the presence of hydrogen peroxide (H2O2), the CeO2/Co3O4 HNs display high peroxidase-like activity, catalyzing the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) and resulting in a color change from transparent to blue. The oxidized TMB (ox-TMB) is subsequently reduced to TMB due to the reducibility of ascorbic acid (AA), restoring the original color of solution. Consequently, a straightforward and efficient "On-Off" colorimetric sensor has been established for the accurate detection of H2O2 and AA, with detection limits (LOD) of 3.56 and 0.179 μM, respectively. In summary, the prepared colorimetric sensor offers numerous advantages, including ease of operation, cost-effectiveness, rapid response, and effective visual monitoring, which holds substantial promise for applications in detection of hydrogen peroxide and ascorbic acid. [Display omitted] The CeO2/Co3O4 hollow nanocubes with exceptional peroxidase-like activity have been successfully synthesized by employing ion exchange process and subsequent calcination method. This work establishes an effortless, cost-effective, and highly efficient "On-Off" colorimetric sensor for H2O2 and ascorbic acid, with color changes serving as the basis for monitoring.