Heterojunction MnO2-nanosheet-decorated Ag nanowires with enhanced oxidase-like activity for the sensitive dual-mode detection of glutathione

• Published in: Nanoscale 2022-10, Vol.14 (41), p.15340-15347
• Main Authors: Lin, Tian, Huang, Zijun, Weidan Na, Liu, Yuanyuan, Wang, Shuai, He, Yu, Cheng, Wenjing, Huang, Tianzi, Zhao, Li, Li, Tongxiang
• Format: Article
• Language: English
• Subjects: Biomimetics; Biosensors; Catalytic activity; Colorimetry; Enzymes; Glutathione; Heterojunctions; Hydrogen peroxide; Manganese dioxide; Nanomaterials; Nanosheets; Nanowires; Oxidase; Oxidation; Redox reactions
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d2nr04294k

The biocatalytic design of nanomaterials with enzyme-like activity is considered a reliable and promising toolkit for the generation of diagnostic agents in complex biological microenvironments. However, the preparation of nanomaterials while maintaining a high catalytic activity in tumor cells (pH 6.0–6.5) poses a prominent challenge. Herein, we constructed a biomimetic enzyme-trigged dual-mode system with colorimetry at 652 nm and photothermal biosensors to detect glutathione based on hollow MnO2-nanosheet-decorated Ag nanowires (Ag@MnO2) as an oxidase-like nanozyme. As expected, Ag@MnO2 catalyzed the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) in the absence of H2O2, leading to a blue-colored oxidized TMB (oxTMB) that displayed oxidase-like activity in pH 6.0. Interestingly, the portable dual-mode colorimetry and photothermal method for GSH was developed based on the redox reaction between GSH and oxTMB. This detection method exhibited a wide linear range of 0.1–55 μM for GSH with a low detection limit of 0.08 μM. This work highlights a new insight into nanotechnology by taking advantage of biomimetic design in biological analysis.