Ultrathin-FeOOH-coated MnO2 nanozyme with enhanced catalase-like and oxidase-like activities for photoelectrochemical and colorimetric detection of organophosphorus pesticides

• Published in: Food chemistry Vol. 445; p. 138716
• Main Authors: Zuo, Maoding, Yang, Yuncong, Jiang, Su, Zhu, Chenyu, Han, Yun, Hu, Juan, Ren, Kewei, Cui, Lin, Zhang, Chun-Yang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2024
• Subjects: alkaline phosphatase; biosensors; catalytic activity; colorimetry; dephosphorylation; detection limit; Dual-mode biosensor; electric current; food chemistry; food safety; Food safety monitoring; manganese dioxide; On-site detection; Organophosphate pesticides; organophosphorus compounds; Spinach; Ultrathin-FeOOH-coated MnO2 nanozyme; Ultrathin-FeOOH-coated MnO2 nanozyme; Dual-mode biosensor; On-site detection; Organophosphate pesticides; Spinach; Food safety monitoring
• ISSN: 0308-8146; 1873-7072; 1873-7072
• DOI: 10.1016/j.foodchem.2024.138716

•A dual-mode biosensor was developed for detection OPPs based on MO@FHO nanozyme.•The MO@FHO nanozyme was used with enhanced catalase-like and oxidase-like activities.•This biosensor can efficiently differentiate OPPs from organochlorine pesticides.•This assay realized the food analysis in the complex biological matrices. Herein, we develop a dual-mode biosensor for photoelectrochemical and colorimetric detection of organophosphate pesticides (OPPs) based on ultrathin-FeOOH-coated MnO2 (MO@FHO) nanozyme. In this biosensor, OPPs can inhibit the alkaline phosphatase (ALP) activity and hinder the dephosphorylation of l-ascorbic acid-2-phosphate, preventing the decomposition of MO@FHO nanozyme and inducing both a photoelectrochemical (PEC) signal and the colorimetric change. The MO@FHO nanozyme not only possesses an enhanced catalase-like activity to degrade H2O2 for the generation of an improved cathodic photocurrent, but also exhibits an excellent oxidase-like activity to oxidize 3,3,5,5-tetramethylbenzidine with high catalytic efficiency. This biosensor displays a detection limit of 50 pmol/L for the PEC mode and a detection limit of 0.8 nmol/L for the colorimetric mode. Moreover, this biosensor exhibits excellent performance in complex biological matrices, and the smartphone-based visual sensing platform facilitates rapid and sensitive detection of OPPs, holding promising applications in food safety monitoring, and on-site detection.