Inorganic Chemicals Industry ›› 2025, Vol. 57 ›› Issue (6): 35-42.doi: 10.19964/j.issn.1006-4990.2024-0335

• Research & Development • Previous Articles     Next Articles

Study on preparation of cerium dioxide quantum dot nanozymes and their application in colorimetric detection of ascorbic acid

TANG Qi1(), SUN Tao1,2,3, XUE Bin1,2,3,4()   

  1. 1. Department of Chemistry,College of Food Science and Technology,Shanghai Ocean University,Shanghai 201306,China
    2. Laboratory of Quality and Safety Risk Assessment for Aquatic Product on Storage and Preservation(Shanghai),Ministry of Agriculture,Shanghai 201306,China
    3. National Experimental Teaching Demonstration Center for Food Science and Engineering(Shanghai Ocean University),Shanghai 201306,China
    4. Marine Biomedical Science and Technology Innovation Platform of Lingang Special Area,Shanghai 201306,China
  • Received:2024-06-12 Online:2025-06-10 Published:2024-07-11
  • Contact: XUE Bin E-mail:409732677@qq.com;bxue@shou.edu.cn

Abstract:

The morphology and size of nanozymes significantly affect their mimetic enzyme catalytic activity.In order to improve the substrate catalytic activity of CeO2 as a nanozyme and broaden its application range,using cerium nitrate as the precursor and citric acid as the structure-directing substance,CeO2 quantum dots(CeO2 QDs) with good crystallinity and small particle size were prepared by one-pot hydrothermal method.The small size effect and rich surface defects of CeO2 QDs could expose more substrate contact active sites,thereby endowing it with oxidase-liked activity.The optimal CeO2 quantum dot nanozyme,CeO2 QDs-6,with the maximum particle size distribution at (4.0±0.6) nm,showed better oxidase enzyme kinetic characteristics than natural enzymes,with the Michaelis kinetic constant as low as 0.165 mmol/L and the maximum reaction rate up to 9.11×10-8 mol/(L·s).Based on the antioxidant activity of ascorbic acid,a rapid,sensitive and highly selective CeO2 QDs-6 ascorbic acid colorimetric detection probe was constructed.Under the optimized conditions,this probe had good ascorbic acid detection performance in the linear range of 1.0~8.0 μmol/L,the lowest detection limit was 148 nmol/L,and showed certain feasibility in the detection of milk samples.

Key words: cerium dioxide, nanozyme, oxidase-liked activity, colorimetric analysis, ascorbic acid

CLC Number: