Dendritic-like MXene quantum dots@CuNi as an efficient peroxidase candidate for colorimetric determination of glyphosate

• Published in: Journal of colloid and interface science 2024-05, Vol.661, p.533-543
• Main Authors: Guo, Yali, Li, Xiaotian, Shen, Peng, Li, Xingchuan, Cheng, Yonghua, Chu, Ke
• Format: Article
• Language: English
• Subjects: catalytic activity; colorimetry; CuNi bimetal; Density functional theory; detection limit; fluorescence; glyphosate; hot water treatment; hydrogen; MXene quantum dots; Nanozyme; oxidation; peroxidase
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2024.01.177

[Display omitted] Oxidized MXene quantum dots@CuNi bimetal (MQDs@CuNi) were firstly prepared through a simple hydrothermal method. Compared to the controlled samples, MQDs@CuNi1:1 showed the highest peroxidase-like activity. The catalytic mechanism of MQDs@CuNi1:1 was investigated using a steady-state fluorescence analysis, which showed that MQDs@CuNi1:1 efficiently decomposes H2O2 and produces highly reactive hydroxyl radicals (OH). Furthermore, theoretical calculations showed that the remarkable catalytic activity of MQDs@CuNi1:1 originates from the interaction between CuNi bimetal and MQDs to promote the activation and decomposition of H2O2, making it easier to combine with the hydrogen at the end of 3,3′,5,5′-Tetramethylbenzidine (TMB). Accordingly, a sensitive colorimetric sensor is proposed to detect glyphosate (Glyp), displaying a low detection limit of 1.13 µM. The work will provide a new way for the development of high-performance nanozyme and demonstrate potential applicability for the determination of pesticide residues in environment.