Bimetallic AuPt alloy/rod-like CeO2 nanojunctions with high peroxidase-like activity for colorimetric sensing of organophosphorus pesticides

• Published in: Mikrochimica acta (1966) Vol. 190; no. 6; p. 220
• Main Authors: Chen, Di-Nan, Mao, Yan-Wen, Qu, Ping, Wang, Ai-Jun, Mei, Li-Ping, Feng, Jiu-Ju
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.06.2023; Springer Nature B.V
• Subjects: Acid phosphatase; Analytical Chemistry; Ascorbic acid; Bimetals; Cerium oxides; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Colorimetry; Hydrogen peroxide; Microengineering; Nanochemistry; Nanorods; Nanotechnology; Original Paper; Peroxidase; Pesticides; Soil water; Vitamin C; Nanojunctions; Peroxidase-like nanozyme; Malathion; Colorimetry; Acid phosphatase
• ISSN: 0026-3672; 1436-5073
• DOI: 10.1007/s00604-023-05757-4

Organophosphorus pesticides (OP) have extensive applications in agriculture, while their overuse causes inevitable residues in food, soil, and water, ultimately being harmful to human health and even causing diverse dysfunctions. Herein, a novel colorimetric platform was established for quantitative determination of malathion based on peroxidase mimic AuPt alloy decorated on CeO 2 nanorods (CeO 2 @AuPt NRs). The synthesized nanozyme oxidized colorless 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H 2 O 2 . Besides, the oxidized TMB was inversely reduced by ascorbic acid (AA), which were originated from hydrolysis of L-ascorbic acid-2-phosphate (AA2P) with the assistance of acid phosphatase (ACP). Based upon this observation ACP analysis was explored by colorimetry, showing a wid linear range of 0.2 ~ 3.5 U L −1 and a low limit of detection (LOD = 0.085 U L −1 , S/N  = 3). Furthermore, malathion present in the colorimetric system inhibited the activity of ACP and simultaneously affected the generation of AA, in turn promoting the recovery of the chromogenic reaction. Based on this, the LOD was decreased to 1.5 nM ( S/N  = 3) for the assay of malathion with a wide linear range of 6 ~ 100 nM. This simple colorimetric platform provides some informative guidelines for determination of other pesticides and disease markers. Graphical Abstract