Metal−organic frameworks-derived MnO2/Mn3O4 microcuboids with hierarchically ordered nanosheets and Ti3C2 MXene/Au NPs composites for electrochemical pesticide detection

• Published in: Journal of hazardous materials Vol. 373; pp. 367 - 376
• Main Authors: Song, Dandan, Jiang, Xinyu, Li, Yanshan, Lu, Xiong, Luan, Sunrui, Wang, Yuanzhe, Li, Yan, Gao, Faming
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.07.2019
• Subjects: AChE biosensor; Methamidophos; MOF-derived MnO2/Mn3O4; Ti3C2MXene/Au NPs; MOF-derived MnO2/Mn3O4; AChE biosensor; Ti3C2MXene/Au NPs; Methamidophos
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2019.03.083

[Display omitted] •MnO2/Mn3O4 composed of vertically aligned, highly ordered nanosheets were prepared.•MnO2/Mn3O4 and MXene/Au NPs were used for constructing sensing platform.•The AChE-Chit/MXene/Au NPs/MnO2/Mn3O4/GCE exhibited superior sensing performances. Transition metal oxides (TMOs) derived from metal − organic frameworks (MOF) combined with two-dimensional (2D) transition metal carbides possibly pave an innovative pathway for designing promising biosensors. Herein, a novel electrochemical sensing platform has been fabricated for ultra-sensitive determination of organophosphorus pesticides (OPs), based on MOF-derived MnO2/Mn3O4 and Ti3C2 MXene/Au NPs composites. Remarkably, the three-dimensional (3D) MnO2/Mn3O4 hierarchical microcuboids derived from Mn-MOF are composed of vertically aligned, highly ordered nanosheets, and further combined with MXene/Au NPs yields synergistic signal amplification effect, with outstanding electrochemical performance, large specific surface area, and good environmental biocompatibility. Under the optimum conditions, the reported sensing platform AChE-Chit/MXene/Au NPs/MnO2/Mn3O4/GCE can be utilized to detect methamidophos in a broad concentration range (10−12–10−6 M), together with a good linearity (R = 0.995). Besides that, the biosensor possesses a low limit of detection (1.34 × 10−13 M), which far exceeds the maximum residue limits (MRLs) for methamidophos (0.01 mg/kg) established by European Union. Additionally, the feasibility of the proposed biosensor for detecting methamidophos in real samples has been demonstrated with excellent recoveries (95.2%–101.3%). Interestingly, the unique structures and remarkable properties of these composites make them attractive materials for various electrochemical sensors for monitoring either pesticide residuals or other environmentally deleterious chemicals.